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dplatt@coop.radagast.org (Dave Platt): May 31 11:13AM -0700 In article <a4021516-0195-49a3-8685-b446a78020ab@googlegroups.com>, >out of phase/polarity at some >point in the chain inside the >player?   As I recall: in some CD players (mostly very old ones?), there's only a single DAC, which is shared between the two channels. The "left" and "right" samples are converted back to analog at slightly different times, in alternating sequence. The analog voltage coming out from the DAC is then fed to a pair of sample-and-hold circuits, one per channel, and these then feed the (low-pass) analog reconstruction filters.   As a result of this, there's a slight phase delay (equal to the actual DAC conversion time, or half of the nominal sample rate for the stereo signal) introduced between the two channels. This would tend to "pull" the perceived stereo image slightly to one side, since our ear/brain systems are sensitive to a signal's inter-aural arrival times as well as to inter-aural amplitude differences.   [I used this trick years ago as a way of enabling a videogame system to convert a monaural sound sample to one which appeared to move left and right, quite smoothly - a simple DSP algorithm did both sample interpolation and filtering, to create timing and amplitude and frequency-response differences between two copies of the sampled sound. It could even introduce the equivalent of Doppler shift, to mimic a sound source moving towards or away from the listener. My first patent ever!]   It sounds as of the CDP101 used a "tweaked" reconstruction filter, to introduce a bit of phase difference between the analog signals that would partially cancel out the phase difference introduced by the use of the single DAC.   I don't think I've seen the "one DAC, two sample-and-hold" technique used in a CD or similar media player in a lot of years. Stereo (or even 5-channel) DACs are jellybean parts these days.

dplatt@coop.radagast.org (Dave Platt): May 31 11:18AM -0700 In article <67e9586e-848b-4a98-8095-cae6430fec09@googlegroups.com>,   >The next week he came in with the CD, and I >compared it to the copy in my inventory: His was >a REMASTER....   And, some remasters are dreadful. Not infrequently the remastering engineer has been of the "louder is better" school, and the remastered disc suffers from serious signal compression and (more than occasionally) actual clipping. The dynamic range of the remaster is often poorer than that of the original CD.   The spectral balance will also often be "played with".

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 01 04:37AM +1000 > out of phase/polarity at some > point in the chain inside the > player?   **It did with the CDP-101, because only one DAC was used and shared between left and right channels. All (?) other players used two DACs (one for each channel) and the delay was not required. For the record, I just checked the schematic of the 701. The 701 used two DACs. One for each channel. It does not use a delay on one OP amp. Both OP amp feedback resistors are 15k, paralleled by a 75pF cap. This likely contributes to the difference in sound quality noted by many listeners (including me).   -- Trevor Wilson www.rageaudio.com.au

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 01 04:43AM +1000 On 1/06/2017 4:18 AM, Dave Platt wrote: > occasionally) actual clipping. The dynamic range of the remaster is > often poorer than that of the original CD.   > The spectral balance will also often be "played with".   **Indeed. That little trick was used by Mobile Fidelity back in the early 1980s. I found some of their limited edition, heavy duty, virgin vinyl, very expensive LPs, unlistenable. I recall the damage MF did to my favourite female artist - Crystal Gayle, on her seminal LP, Don't It Make My Brown Eyes Blue. The bog-standard LP was a glorious thing. The MF was something else entirely and a good deal more expensive too. I never purchased another MF product. Well, except my UHQR Pink Floyd - Dark Side Of The Moon. It is still unopened and the last figure I saw was about US$1,500.00. A nice return on my 25 Bucks.   -- Trevor Wilson www.rageaudio.com.au

bitrex <bitrex@de.lete.earthlink.net>: May 31 05:12PM -0400 On 05/30/2017 02:54 AM, Phil Allison wrote:   > I reckon there must have been a bit of dead cocky on the lens.   > .... Phil   It would look great with my Onkyo TX-2500 mk II receiver in my "retro stereo corner."   Give ya one fiddy for it.

amdx <nojunk@knology.net>: May 31 04:50PM -0500 On 5/30/2017 1:54 AM, Phil Allison wrote:   > I reckon there must have been a bit of dead cocky on the lens.   > .... Phil   I still have a Magnavox (NAP) FD 1040 that I bought in 1984, not quite as old as yours. I used it for years and then it quit working, I couldn't locate the problem. I worked for an NAP authorized service center at the time and even calling tech support didn't lead to a repair. So I sent it to the NAP factory service center for repair. They had it for well over a month and returned it saying they could not fix the problem. I mentioned the situation to one of our other techs, he said, "let me take a look at it" he put a wire through all the vias and resoldered them. He gave me back a working CD Player!   Mikek

jurb6006@gmail.com: May 31 03:33PM -0700 >"Is there something I don't know about CD players"   As been pointed out, the channels are read sequentially.   There are a few things most people don't know about CDs. First of all that they could be quadrophonic. It was never involved, no quad CDs were made and no quad CD players were made.   Also the digital compression scheme used was necessary to make the CD small enough to facilitate in dash CD players in cars of the time, which generally had a predetermined space for the stereo. (that is also why they are not 48 KHz)This facilitated aftermarket stereos and has been changed in more recent cars. The strive to make it non standard so that they have a captive market on the stereos.   And the LASER beam is not a beam at all, it is conical shape. this means that on the bottom surface of the CD where all the scratches and dirt are, the pickup of the signal does not depend on a teeny tiny area.   On a stamped CD, the pits are not darkened at all. They cancel the light out by being ¼ wavelength of light deeper. There is no mask nor pigment involved, unlike burned CDs.   In the beginning of stamping CDs in the US, Teelarc could not produce a defect free disk. They had to get engineers from overseas to figure out what they were doing wrong. So much for "America number one ?".   All obsolete. Now DVDs are obsolete. Now bluray is obsolete. They got a holographic disk now that holds so much more data that nobody can use it. Thatis the only reason it is not on shelves. Also, do you really want your entire library of movies and whatever on one disk ? Scratch that.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 01 08:45AM +1000 On 1/06/2017 4:43 AM, Trevor Wilson wrote: > never purchased another MF product. Well, except my UHQR Pink Floyd - > Dark Side Of The Moon. It is still unopened and the last figure I saw > was about US$1,500.00. A nice return on my 25 Bucks.   **Scratch that. Looks like my DSOTM UHQR LP is now worth a little North of 2 Grand. Gotta be happy with that. Factory sealed, still has the guarantee label stuck to it.   -- Trevor Wilson www.rageaudio.com.au

thekmanrocks@gmail.com: May 31 04:05PM -0700 Trevor Wilson wrote: "**It did with the CDP-101, because only one DAC was used and shared between left and right channels. All (?) other players used two DACs (one for each channel) and the delay was not required. For the record, I just checked the schematic of the 701. The 701 used two DACs. One for each channel. It does not use a delay on one OP amp. Both OP amp feedback resistors are 15k, paralleled by a 75pF cap. This likely contributes to the difference in sound quality noted by many listeners (including me).   -- Trevor Wilson www.rageaudio.com.au "     Thanks, Trevor W, for that cogent explanation, and for not cowing to the sudden dip in S/N ratio in this thread.

thekmanrocks@gmail.com: May 31 04:14PM -0700 jurb wrote: "As been pointed out, the channels are read sequentially. "   On early machines such as the CDP101. Trevor did mention that subsequent models began incorporating DACs for each channel.     Something I am aware of that you didn't bring up: Pre-emp/De-emp. Some CDs were mastered with a rising high- end frequency response, and a corresponding attenuation in the player. Sort of a "Dolby NR" for CDs I guess?   Nothing I ripped even in EAC flags the pre-emp, even though the vast majority of my CD collection are from the era when pre-emphasis was most likely to be used. I would have to load the WAVs ripped from every CD in my collection into a DAW and run a spectro on it to see if it looked unusually top- heavy, suggesting emphasis. Can't always tell by ear.

etpm@whidbey.com: May 31 04:49PM -0700 On Wed, 31 May 2017 11:18:36 -0700, dplatt@coop.radagast.org (Dave Platt) wrote:   >occasionally) actual clipping. The dynamic range of the remaster is >often poorer than that of the original CD.   >The spectral balance will also often be "played with".   Years ago when Pink Floyd's Dark Side Of The Moon came out on CD I bought a copy and was amazed at how much better it sounded than the vinyl. Then Happy Trails by Quicksilver Messenger Service came out on CD and I was anticipating a much better sounding copy. Nope. It sounded just as bad as my vinyl and reel to reel copies. I guess the master tapes done by Pink Floyd were much better than the ones that held Quicksilver's music. Eric

thekmanrocks@gmail.com: May 31 05:02PM -0700 Dave Platt wrote: "And, some remasters are dreadful. Not infrequently the remastering engineer has been of the "louder is better" school, and the remastered disc suffers from serious signal compression and (more than occasionally) actual clipping. The dynamic range of the remaster is often poorer than that of the original CD.   The spectral balance will also often be "played with". "     As was the case with this customer's version of the Wonder CD I was playing in the store. Needless to say, I convinced him to buy the unremastered orignal!

Michael Black <et472@ncf.ca>: May 31 08:28PM -0400

Phil Allison <pallison49@gmail.com>: May 31 05:29PM -0700 Dave Platt wrote:   ----------------- > "pull" the perceived stereo image slightly to one side, since our > ear/brain systems are sensitive to a signal's inter-aural arrival > times as well as to inter-aural amplitude differences.   ** You need to apply some common sense before making such conclusions. What does such a tiny delay amount to in distance ?   Answer:   your head being offset by 1.7mm from exact centre of a pair of speakers.     You are employing the worst of audiophool non-think which holds that IF it exists it MUST be audible.   Bollocks.     .... Phil

Phil Allison <pallison49@gmail.com>: May 31 05:32PM -0700 Trevor Wilson wrote:   --------------------       > feedback resistors are 15k, paralleled by a 75pF cap. This likely > contributes to the difference in sound quality noted by many listeners > (including me).     ** More TW audiophool nonsense.   There is no audible difference and the 15k resistor business is an obvious red herring.   Just do a tiny bit of math on those numbers.       ..... Phil

Phil Allison <pallison49@gmail.com>: May 31 05:35PM -0700 amdx wrote:   -------------     > me take a look at it" he put a wire through all the > vias and resoldered them. > He gave me back a working CD Player!   ** That is a nasty and pretty rare fault.   I've had to do the same only twice ever.   Few techs would even think of it.     .... Phil

Phil Allison <pallison49@gmail.com>: May 31 05:37PM -0700 thekma...@gmail.com wrote:   -------------------------- > www.rageaudio.com.au "   > Thanks, Trevor W, for that cogent > explanation,   ** ROTFL !!   TW is spewing his usual audiophool nonsense while a know nothing idiot is lapping it up.         ..... Phil

Clifford Heath <no.spam@please.net>: Jun 01 10:14AM +1000 On 01/06/17 10:37, Phil Allison wrote: >> explanation,   > ** ROTFL !!   > TW is spewing his usual audiophool nonsense while a know nothing idiot is lapping it up.   Maybe. Interesting related story: I built a stereo sonar, using a 40KHz transmitter with two receivers 5cm each side. The aim was to resolve the angle of the response echo. Because the receiver circuits detected a response passing a threshold, and because the receivers would be still resonating from the transmit pulse, the echo could arrive either in or out of phase, so the threshold was passed a cycle earlier or later. 40KHz acoustic wavelength is 7mm, so there was a 10 degree sawtooth uncertainty in the angle of the received signal. A time delay of one cycle is 25us.   The only way around this is to not use thresholding, but to digitize each receiver's waveform and compute the departure from normal ring-down caused by a reflected signal.   Since our ears use relative phase to locate signals, I'd think that a high frequency phase shift (at say 4KHz) would very likely affect the stereo imaging.   Clifford Heath.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 01 10:50AM +1000 On 1/06/2017 10:32 AM, Phil Allison wrote:   > ** More TW audiophool nonsense.   > There is no audible difference and the 15k resistor business is an obvious red herring.   > Just do a tiny bit of math on those numbers.   **If there is no audible difference, why did Sony use different value resistors in the 101 and the same values in the 701? I presume you are suggesting that there is a measurable difference, but that difference is inaudible?     -- Trevor Wilson www.rageaudio.com.au

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 01 10:53AM +1000 On 1/06/2017 10:35 AM, Phil Allison wrote:   > I've had to do the same only twice ever.   > Few techs would even think of it.   > .... Phil   **Not really. The Magnavox was identical the early Philips/Marantz units and was built in Belgium. Those whacky Belgians could have learned a great deal from Sony about how to make decent PCBs. The lasers were great, but the PCBs were poorly assembled.   -- Trevor Wilson www.rageaudio.com.au

etpm@whidbey.com: May 31 06:15PM -0700 On Wed, 31 May 2017 20:28:14 -0400, Michael Black <et472@ncf.ca> wrote:   >new medium. I don't know whether it applies here, I have the record, but >don't have it on CD.   > Michael All my recordings of Happy trails were obviously made from the same master tapes. I can hear the exact same noise in the same places on them all. In fact, the CD almost sounds like it was recorded from the LP I have. I saw Quicksilver live in San Jose way back when. It was a great venue and a great concert. And I was listening to Who Do You Love just a couple days ago which made me think of the difference in the quality of the recordings. Eric

"pfjw@aol.com" <pfjw@aol.com>: May 31 11:22AM -0700 On Wednesday, May 31, 2017 at 12:34:50 PM UTC-4, Miguel Giménez wrote:   May be a focus problem unrelated to laser?   Likely.   Peter Wieck Melrose Park, PA

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 01 04:50AM +1000 On 31/05/2017 10:29 PM, Miguel Giménez wrote: > original spare parts, and the three died months after.   > Why this happen? Do I need to adjust laser current after change? Are > they basically unreliable?   **IME modern lasers are not reliable devices. The older ones were very reliable. Why? Dunno exactly. If you look at an old laser from a Sony or a Philips CD player, you will likely see a very carefully (hand assembled?) laser unit, constructed from carefully machined aluminium alloy, precisely aligned, using a high quality glass lens. Replacement cost typically ran to several hundred Dollars. Modern lasers are all made in China, from plastic and steel and are almost certainly machine assembled. Cost, typically runs at around $20.00 or so. With massive cost reductions in any product, something usually has to give.     -- Trevor Wilson www.rageaudio.com.au

ohger1s@gmail.com: May 31 12:18PM -0700 On Wednesday, May 31, 2017 at 8:30:01 AM UTC-4, Miguel Giménez wrote:   > -- > Regards > Miguel Giménez   Don't know about your particular drives, but anybody who did any kind of audio work in the 90s knows that Sony lasers were/are pure, unadulterated shit. I'm being kind here.   There were tons of otherwise very nice Aiwa three CD carousel combo stereos that had decent power and respectable sound (given the market) and enough LEDs flashing to keep the Walmart buyers enthralled. Unfortunately, they all came equipped with Sony lasers. We pulled the plug on doing these after the first few failed and recommended that our customers use these for "garage" radios.   Now I've heard that there were/are Chinese counterfeits for these and this might explain repeat failures, but it doesn't explain why so many Aiwa and Sony brand CD players came in for weak or dead lasers in two years.

whit3rd <whit3rd@gmail.com>: May 31 04:16PM -0700 On Wednesday, May 31, 2017 at 11:50:43 AM UTC-7, Trevor Wilson wrote: > reliable. Why? Dunno exactly. If you look at an old laser from a Sony or > a Philips CD player, you will likely see a very carefully (hand > assembled?) laser unit...   Usual failure mode for a surface-emitting laser is some kind of dirt migration in the surface. This has NOT been getting worse, the chemistry and material preparation is as good now as it has ever been, and even UV semiconductor lasers are working well for long periods of time.   Another possible reason for failure is ... lack of use. The normal electrical bias during operation is intended to keep sweeping impurities out of the sensitive region. If you just store the unit on the shelf, and DON'T operate it for a few hours a week, the (equivalent of) dust bunnies just pile up.   The implication is, use your CD/DVD/BD readers and burners every week or so. They might just go bad on the shelf otherwise.

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"Miguel Giménez" <me@privacy.net>: May 31 02:29PM +0200 Hi   In the last years I have changed twice the laser unit of my Aiwa CD reader and once the unit of my mom's Sony reader. The three were original spare parts, and the three died months after.   Why this happen? Do I need to adjust laser current after change? Are they basically unreliable?   TIA   -- Regards Miguel Giménez

"pfjw@aol.com" <pfjw@aol.com>: May 31 05:55AM -0700 On Wednesday, May 31, 2017 at 8:30:01 AM UTC-4, Miguel Giménez wrote:   > -- > Regards > Miguel Giménez   Never had or observed this problem per-se. Many times I have seen the output level of the laser poorly adjusted, poorly focused or not precisely aligned, especially if resulting from a home repair. Admittedly a small sample, perhaps about 20 players in all.   Peter Wieck Melrose Park, PA

"Miguel Giménez" <me@privacy.net>: May 31 06:34PM +0200 > Never had or observed this problem per-se. Many times I have seen the output level of the laser poorly adjusted, poorly focused or not precisely aligned, especially if resulting from a home repair. Admittedly a small sample, perhaps about 20 players in all.   > Peter Wieck > Melrose Park, PA   The replacements worked OK for some months, then failed abruptly. The symptom was always: insert disk -> some seconds trying to read disk -> disk ejection. May be a focus problem unrelated to laser?   Also, there were neither smokers nor floating dust near the devices.   -- Regards Miguel Giménez

"None" <none@nospam.org>: May 31 07:31AM -0400 < thekma @ dumbfuck.org > wrote in message news:3813cea3-6910-4a51-bc36-f9af3e9b5cf6@googlegroups.com... > middle-aged college-educated > white male is a liability, it > seems. Go figure!   LOL! "College educated"! When your resume says that it took you seven years trying to get through a two-year community college, employers may not be impressed. They can (and will) do a google search, and find that you've bragged that the only reason you "graduated" was because the faculty was sick of seeing you failing the same classes year after year, and they just wanted to get rid of you. Can you blame them? Nobody wants to see that moronic blank stare, indicating a fog of non-comprehension. If you've found a job at the used crap store, where they're willing to hire a retarded dumb fuck like you, maybe you should keep it instead of pretending that you can handle a real job.   Being a fucking moron is a liability. Being unable to add two plus two is a liability. HDKAD. CKWAFA!

"pfjw@aol.com" <pfjw@aol.com>: May 31 05:51AM -0700 On Wednesday, May 31, 2017 at 7:32:00 AM UTC-4, None wrote:   Hi, "Barry"?   Once upon a time, you gave reasonable advice. Now it seems you are starting to eat what Phil eats, but without the same level of knowledge.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 31 06:54AM +1000 On 30/05/2017 9:13 PM, Phil Allison wrote:     > In terms of tech specs, sound quality, features and ease of use - it > is still one of the best CD players ever made.   **Sound quality? Nope. The CDP701 (released close to the same time as the 101) was far better. I recall listening to both at a Sony demo, through their ES series Sony electronics and those very good flat diaphragm Sony speakers. The 701 completely outclassed the 101. One of my clients had both machines and we listened extensively to them (compared them with 2nd generation master tapes of Hot August Night on his Studer) and the 701 was a far better sounding machine. Even the Sony demo guy, who claimed that there would be no sonic difference, was surprised. That said, a decent multibit machine (like the early Sony and Philips machines) will sound better than those horrible single bit ones released in the late 1980s.     -- Trevor Wilson www.rageaudio.com.au

thekmanrocks@gmail.com: May 30 02:21PM -0700 Trevor Wilson wrote: "On 30/05/2017 9:13 PM, Phil Allison wrote:     > In terms of tech specs, sound quality, features and ease of use - it > is still one of the best CD players ever made.   **Sound quality? Nope. The CDP701 (released close to the same time as the 101) was far better. I recall listening to both at a Sony demo, through their ES series Sony electronics and those very good flat diaphragm Sony speakers. The 701 completely outclassed the 101. One of my clients had both machines and we listened extensively to them (compared them with 2nd generation master tapes of Hot August Night on his Studer) and the 701 was a far better sounding machine. Even the Sony demo guy, who claimed that there would be no sonic difference, was surprised. That said, a decent multibit machine (like the early Sony and Philips machines) will sound better than those horrible single bit ones released in the late 1980s.     -- Trevor Wilson "   Was the CDP101 vs 701 test done with the same exact source (CD) in the same listening environment, connected to the same system?     Otherwise such tests are invalid.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 31 07:45AM +1000 On 31/05/2017 6:54 AM, Trevor Wilson wrote: > surprised. That said, a decent multibit machine (like the early Sony and > Philips machines) will sound better than those horrible single bit ones > released in the late 1980s.   Was the CDP101 vs 701 test done with the same exact source (CD) in the same listening environment, connected to the same system?     Otherwise such tests are invalid.   **Did you bother reading what I wrote? Go back and read it CAREFULLY.   In truth, the only invalid part of the MANY tests I did, comparing the two machines, was the fact that none were done blind. An oversight I regret.     -- Trevor Wilson www.rageaudio.com.au

Phil Allison <pallison49@gmail.com>: May 30 08:45PM -0700 > (CD) in the same listening environment, > connected to the same system?   > Otherwise such tests are invalid.   ** TWs listening tests are totally invalid - cos he used the audiophool method.   Machine A plays, stop, muck about, have a chat then machine B plays.   Absolute bollocks.   As a matter of fact, I carried out a blind testing session between my CDP101 and a borrowed CDP701 for a customer. He had a well damped room with Quad ESL63s at the time driven by an expensive Sony amp. It was all nicely set up for best imaging etc.   Both CD players were out in the hallway, so he could not see them or me. All I had to do was swap RCA leads and CDs between machines.   Try as he might, using his favourite classical tracks, he could not tell the machines apart.   Happy that there was no audible difference, he opted to buy the more expensive model.   He merely wanted to be *certain* the cheaper model was not actually better.       ..... Phil

thekmanrocks@gmail.com: May 31 01:30AM -0700 Phil Allison wrote: "Try as he might, using his favourite classical tracks, he could not tell the machines apart.   Happy that there was no audible difference, he opted to buy the more expensive model.   He merely wanted to be *certain* the cheaper model was not actually better.   ..... Phil "   I rest my case: the SOURCE(what's on the medium) matters most!

jurb6006@gmail.com: May 31 01:57AM -0700 Does the 101 have the delay to match the phase of the channels ?

jurb6006@gmail.com: May 31 02:09AM -0700 >"** TWs listening tests are totally invalid - cos he used the audiophool method.   Machine A plays, stop, muck about, have a chat then machine B plays.   Absolute bollocks. "   Actually with stamped CDs it would be valid to just use two copies of the same album. If there is ay doubt switch them but we know that sound quality had very little to do with the audio quality. It is just a matter of how many errors does it have to cover up.   They are stamped, you get two of them right next to each other from the shelf and they are likely to be the same batch and have the same errors. And the only errors that will have any real effect on sound quality will be those pertaining to the deemphasis.   Two disks and a toggle switch would do just fine. then switch the disks ad see if the more favorable rating follows it ort stays with the player.   Kida like splitting a bag of weed when your scalee is broken. "You split I'll pick" or vice versa. Whoever is splittlg is going to get them as close as humanly possible because he knows he gets the smaller one. Or whichever one is perceived as smaller by the picker.   Ever hear of scraping ? They use like a gouge to scrape metal plates to within millionths of an inch. There is no reference because these ARE the reference. they are the standard to which the ways of machines must adhere for flatness and straightness.   they use three plates, why ? Well, you blue it up and then separate the plates and observe the bluing. This really is an art. You can get two plates pretty flat, but there is ONE way they can be off and you can't tel. That is if one is slightly convex and the other concave. That is the reason for the third plate. It makes that type of error detectable because to match perfectly the third plate would have to be concave or convex and thus would math one of the two other plates but not the other.   In other words, all this fiddling switching disks every few minutes is a waste of time. Just switch them and rerun the comparison.   Actually I doubt very mny people can hear ant difference between cD players, butin the US would always prefer the one that has a slightly higher output level because it is louder.   You want an audio A/B comparison ? Golden Earring - Moontan, on vinyl. Compare the US version to the European version. BIG difference.

Phil Allison <pallison49@gmail.com>: May 31 02:44AM -0700 jurb...@gmail.com wrote:   ------------------------     > Actually I doubt very mny people can hear ant difference between > cD players, butin the US would always prefer the one that has a > slightly higher output level because it is louder.   ** CD players are built under license to a standard ( Red Book) which requires the audio output is 2.0V rms for max sine wave level.   Makes comparing them pretty easy if you use the same RCA leads and disk.     .... Phil

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 31 08:27PM +1000 > Does the 101 have the delay to match the phase of the channels ?   **Yes. In the feedback of the OP amp after the buffer stage, one OP amp has a 15k resistor in parallel with a 75pF, whilst the other channel has 16k in parallel with a 75pF cap. A bit of a kludge. As I recall, the CDP701 employed two, separate DACs. I could be wrong, so I'll see if I can locate the manual tomorrow.   -- Trevor Wilson www.rageaudio.com.au

thekmanrocks@gmail.com: May 31 03:54AM -0700 Interesting anecdote: I had an Aiwa bookshelf system set up in the store and playing a Stevie Wonder CD. A guy came over and started playing with it, listening to different tracks etc. He said it sounded great, and he bought it.     Next day, he came in, saying he had the "same disc" at home, but that the system did not sound nearly as good as when he played with it in the store. Since he said he had the disc, I asked him to bring his in next time he visited.     The next week he came in with the CD, and I compared it to the copy in my inventory: His was a REMASTER....

thekmanrocks@gmail.com: May 31 04:12AM -0700 Trevor, jurb: R.E. "phase of the channels"     Is there something I don't know about CD players, or how they function? Does the audio arrive out of phase/polarity at some point in the chain inside the player?

"None" <none@nospam.org>: May 31 07:28AM -0400 <t hekma @gmail.com> wrote in message news:a4021516-0195-49a3-8685-b446a78020ab@googlegroups.com... > Is there something I don't know about CD players, or how they > function?   Yes. Pretty much everything about audio is something you don't know. KHF,

gregz <zekor@comcast.net>: May 31 06:37AM >> sound.   > Bass guitar players would only use an 8" speaker for practice, > and then only under duress.   Take a look at Phil Jones bass. Lots of little drivers made by him. He must use some eq I figure.   Greg

tabbypurr@gmail.com: May 30 03:16PM -0700 On Tuesday, 30 May 2017 17:24:01 UTC+1, Jeff Liebermann wrote:   > something that requires regular recharging, such as handheld radios, > and flashlights. I'm doing something wrong with NiMH, but haven't > figured out what.   Discharging too far is their biggest killer. Or to put it another way, mismatched cells. When one flattens the others push current through it & it suffers badly.     NT

oldschool@tubes.com: May 30 11:41AM -0400 On Mon, 29 May 2017 14:40:08 -0500, Ralph Phillips <ralphp@philent.biz> wrote:     >I also use Foxit Reader; but that sucker's bloating up like a beached >whale in August in Florida ...   >RwP   IRFANVIEW can view PDF files??????? That's a new one on me.   I have IRFANVIEW installed, for viewing images, but I dont use it too much. I prefer Acdsee. Mostly because IRFANVIEW always forces small images to fit the screen as a default, and small images look like crap when they expanded. So I have to repeatedly resize each and every image to it's ACTUAL size. That gets real tiring. Acdsee shows the images at their actual size, unless the image is larger than my screen, in which t fits the image to the screen. I dont have to keep adjusting the viewed image size, it just views automatically. Because of that, IRFANVIEW is NOT my default viewer.   FOXIT Reader was once a decent PDF viewer. I used it for several years. A few months ago, I put a larger hard drive in my laptop. Rather than image my setup from the smaller drive, I decided to just reinstall XP from scratch. I was traveling to a destination, and someone had given me a PDF map. I pulled over at a wayside to view it, when I realized that I did not have a PDF viewer installed.   So, I drive to the nearest restaurant that had WIFI, and googled "PDF Viewer". The first one that popped up was Foxit. I was in a hurry and did not have time to piss around. I just wanted to view that PDF map. I installed Foxit reader, and what I saw was so bloated and filled with complicated crap that I wanted no part of it. (And if I recall, it was also full of advertising). I did manage to view my map though. But a few days later, when I was not in a hurry, I again opened that miserable bloated piece of shit, and looked at it. It took me less than 5 minutes to remove it from my computer, and install PDF-Xchange. I thought Adobe's reader was bad, until I tried the latest Foxit. (It's worse). I would not recommend Foxit to anyone.....

jurb6006@gmail.com: May 30 11:25AM -0700 Here's a nice trick if you are still using XP. (also works in Vista)   Get into Windows Explorer and set it to show hidden/system files. Now go find the executable for each of your viewers or aything where you have a choice off different programs to open. Right click the executable and hit "Desktop Create Shortcut.   Drag those shortcuts into the \sendto directory, which will be under your username in Documents and Settings.   Now when you right click a file you can force it to any of the programs at will and not change the file association.   I tried it in Win7 and it gave me all kinds of hell with this access denied. Whose PC is this anyway ? I no longer have Win7.

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"(PeteCresswell)" <x@y.Invalid>: May 30 09:18AM -0400 Per Jeff Liebermann: >rechargeables...   That one was a keeper: thanks.   Is your reason for using LiIon in flashlights the near-zero self-discharge?   I have been using Eneloops, but not in all of my lights.... yet. -- Pete Cresswell

Jeff Liebermann <jeffl@cruzio.com>: May 30 09:24AM -0700 On Tue, 30 May 2017 09:18:23 -0400, "(PeteCresswell)" <x@y.Invalid> wrote:   >Is your reason for using LiIon in flashlights the near-zero >self-discharge?   No. It's my total disgust with the damage done by leaking alkalines. I discovered something new with the last alkaline battery leak. Even though the battery leaks had made a big mess inside the flashlight, it still lit up normally. So, turning on the light to see if it is still alive is NOT a substitute for visual inspection. Argh.   My main reason for getting into flashlights is that I'm bored and wanted to play with some different toys. I've been reading Candle Power Forums for quite a while and thought flashlights might be fun. The major incentive was a non-monetary bet with a friend over the usefulness of bottom of the line LiIon cells. My contention is that they are economically justifiable, while he demands nothing but the best.   Another reason I won't trust alkalines. They die in the box: <http://802.11junk.com/jeffl/crud/Kirkland-AAA-leak.jpg>   I just remembered that I'm suppose to fix an Apple BlueGoof wireless keyboard. The alkaline batteries leaked and the stainless steel screw on cover, into an aluminum housing, it rotted shut. I've tried brute force, with no effect. Chemical attack comes next.   >I have been using Eneloops, but not in all of my lights.... yet.   Same here, but I prefer LiIon. I've been having problems with ordinary NiMH. In addition to self discharge, they don't seem to last through too many charge cycles. Typically, I get about 200 with NiMH and 1200 or more with NiCd. Overall, I do better with NiCd for something that requires regular recharging, such as handheld radios, and flashlights. I'm doing something wrong with NiMH, but haven't figured out what.   Also, LiIon has a much higher maximum discharge current. 20C is common while NiMH is maybe 5C. It's the higher energy density of LiIon that has made power hogs like quadcopters and high power flashlights possible. They could be made to work on NiMH, but performance would suffer. LiIon has also force the introduction of decent battery chargers. One can get away with crude and simple with NiCd and NiMH, but not with LiIon. LiIon requires a well designed charger. Multiple cells charged in series require a balance charger. Many NiCd and NiMH chargers will merrily kill batteries with "quick charge" and various memory effect cures, but even a mediocre LiIon charger will do a reasonable job without killing the cells. Of course, there are plenty of ways to do it wrong, but so far, that's been the exception, not the rule.       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

"D. Peter Maus" <dpetermaus@att.net>: May 30 08:45AM -0500 On 5/24/17 12:22 PM, Michael Black wrote: > I don't think the chain ever deliberately hired "technical people".       At one time, yes they did. My first encounter with Radio Shack was a very pleasant experience. But, they were much different times. Olson, Lafayette, Allied, Burstein-Applebee, even Zalytron, and numerous brick and mortar stores in an area provided incentive for Radio Shack to be a better Radio Shack.   And, since Radio Shack catered to an amateur radio crowd, their sales persons had to be knowledgable, to explain the equipment, as well as licensed to demostrate it. In my area, all the RS stores, at the time, had working ham stations on site, to demostrate their best and newest toys.   When I applied for a job there, I was woefully, at the time, unprepared for the technical requirements of the job, and was told to come back, they'd be glad to have me, but I needed to get more comfortable with the technical aspects of the inventory.   When I told them I was more of an audio guy, and my expertise was in that vein, the GM's eyes perked up, and we had a great conversation. He had been looking for audio people, because the market was moving toward components, as opposed to furniture consoles, and away from the amateur market. And, the licensing requirements for CB were already being discussed as obsolete.   So, yes, at one time, they did require technical knowledge to work at Radio Shack. But that was long ago, in a galaxy far away.   Oh, and, I never did work there. I had also applied at a number of other places, but decided, instead to open my first repair shop, an offshoot of which was designing and building custom audio equipment for the well-heeled in Clayton and LaDue. Great fun.   Good coin, too.   p

thekmanrocks@gmail.com: May 30 09:09AM -0700 D. Peter Maus:   Sorry to hear of such high entry barriers to what was essentially a retail job! I'm facing similar barriers now to re-entry into the office environment: Being a middle-aged college-educated white male is a liability, it seems. Go figure!

"pfjw@aol.com" <pfjw@aol.com>: May 30 05:28AM -0700 The bolt came right out, with only the 'correct' amount of torque required. The entire job took 20 minutes, and now the car is running 'like new'.   Peter Wieck Melrose Park, PA

Foxs Mercantile <jdangus@att.net>: May 30 08:17AM -0500 > The bolt came right out, with only the 'correct' amount of > torque required.   Another "happy camper" that discovered yet another "Shit that just works like it's supposed to."       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

tabbypurr@gmail.com: May 30 06:11AM -0700 > It's appearance, and being > the first cosnumer CD player.   > It represents that era!   My first cd player had the disc upright and played at 1x. I like old electronics generally but saw no merit in that one once better came along.     NT

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Phil Allison <pallison49@gmail.com>: May 29 11:54PM -0700 Hi,   I bought one of the above immediately they appeared on sale in Sydney - in fact I pre-ordered it. For the first week, I had no CDs to put in it !!   With a few minor repairs, it has been working perfectly for 34 years and nowadays getting only occasional use.   Yesterday, I popped a CD in the drawer and it spat it back - so I tried a couple more with the same result.   Fearing the worst, I opened the machine and found some cockroach droppings in the drawer and near the laser assembly. Not much, just a bit.   While doubting this could stop a CDP101 completely, I nevertheless decided to give it a thorough clean up. Took about 15 minutes with a damp cloth, brush & WD40 and finally a dry cloth.   Popped the same CDs back in and it plays them perfectly.   I reckon there must have been a bit of dead cocky on the lens.       .... Phil

thekmanrocks@gmail.com: May 30 03:53AM -0700 Phil Allison:   What a time capsule! Enjoy and take care of that.

Phil Allison <pallison49@gmail.com>: May 30 04:13AM -0700 > Phil Allison:   > What a time capsule!   ** OK - why do you call that ?     > Enjoy and take care of that.     ** I have no intention of doing otherwise.   In terms of tech specs, sound quality, features and ease of use - it is still one of the best CD players ever made.   http://vintage-audio-laser.com/sony/cdp101/sony_cdp-101_5.png       .... Phil

thekmanrocks@gmail.com: May 30 05:14AM -0700 Phil:   It's appearance, and being the first cosnumer CD player.   It represents that era!

"(PeteCresswell)" <x@y.Invalid>: May 29 05:54PM -0400 >use rechargeables.   I suspect that the issue for most people is dollars-and-cents battery costs, but instead whether-or-not the light works when somebody grabs it during a power failure or something after it's been on the shelf for 3 months. -- Pete Cresswell

Jeff Liebermann <jeffl@cruzio.com>: May 29 04:43PM -0700 On Mon, 29 May 2017 17:54:14 -0400, "(PeteCresswell)" <x@y.Invalid> wrote:   >costs, but instead whether-or-not the light works when somebody grabs it >during a power failure or something after it's been on the shelf for 3 >months.   There's another issue, which is what inspired me to get away from alkaline and switch to LiIon and NiMH. Just about every alkaline battery brand that I've tried will leak and rot out the device it is suppose to power. I just recycled yet another 2D Maglite flashlight. At least once per month, I have clean out the guts from a 2way radio, clock, weather station, etc from the crud oozing out of alkaline cells. There must be a better way.   For devices that require AA and AAA cells, I'm using LSD (low self discharge) NiMH cells, mostly Eneloop. I had to use a pair of FRS radios last weekend which were last charged in Dec 2016. 6 months later, the charge indicator showed about 80% charge and they ran the radios all day. Good enough. <https://en.wikipedia.org/wiki/Eneloop#AA_size> See charge retention table.   For flashlights, I've almost finished switching to all LiIon batteries, mostly 18650 and 14500. <http://802.11junk.com/jeffl/crud/LiIon%20Flashlights.jpg> That's about 1/3 of my growing collection of cheap LiIon batteries and flashlights. Why so many? Because most of what arrives is a mixture of not what I ordered, mechanical defects, premature electrical failure, bad design, or bad construction. To insure that things will go awry, I'm also buying nothing but the cheapest LiIon batteries at $0.85/ea for 14500 to $1.30 for 18650. Why buy bottom of the line? Because it's my contention that bottom of the line batteries are a better deal on the basis of cost per energy delivered than buying quality high capacity cells. It will take another 6 months or so to be sure, but so far so good. Cheap 18650 battery capacity at 1.5A, which is at the high end of what a flashlight will draw: <http://802.11junk.com/jeffl/battery-tests/18650.jpg>   Drivel: There's even a web site for cheap flashlight enthusiasts: <http://budgetlightforum.com>   The only fly in the flashlight ointment is the cost of a decent battery charger. Most of the really cheap battery chargers are badly designed, dangerous, or both. For example, this loser sells for about $0.50 with many flashlight and battery combinations: <http://lygte-info.dk/review/Review%20Charger%20Bowei%20HC-103W%20UK.html> How customs even lets them into the country is a mystery.   Before you buy a charger, check here: <http://www.lygte-info.dk/info/indexBatteriesAndChargers%20UK.html> Also avoid any dual battery charger with only one LED light. These charge 2 batteries in parallel, which is a rather bad idea, but will work for one battery at a time.   Real LiIon chargers are quite a bit more expensive. These are good so far: <http://www.ebay.com/itm/301383587686> $10 <http://www.ebay.com/itm/331572608015> $17.20   Bottom line is that you can get a decent bottom of the line flashlight system for: flashlight: $3 to $8 18650 battery: $1.50 Charger $10 ========================== Total $15 (approx) Of course, the expensive charger can be used with multiple flashlights, so the 2nd flashlight will cost only about $5.   For LiIon battery packs with multiple cells, I use a balance charger: <https://hobbyking.com/en_us/catalogsearch/result/?q=imax+b6> The charger is the most important and most expensive part of the system. I built a 10watt LED light, that runs on 11.3VDC, which uses a balance charger.   Oh yes, self discharge. Li-Ion is as good or better than LSD NiMH: <http://batteryuniversity.com/learn/article/elevating_self_discharge> See Tables 3 and 5. There's a rumor that storing a LiIon battery at full charge would shorten its useful life. That was certainly a problem with laptop batteries during the 1990's, but seems to have been eliminated in the current offerings.   Anyway, think rechargeable, recycle your alkalines, and return the flashlights to Costco.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

mike <ham789@netzero.net>: May 29 06:10PM -0700 On 5/29/2017 4:43 PM, Jeff Liebermann wrote: > At least once per month, I have clean out the guts from a 2way radio, > clock, weather station, etc from the crud oozing out of alkaline > cells. There must be a better way.   I'd agree, but many of my devices won't run on that voltage. Wireless power monitors and thermometers, for example. > See charge retention table.   > For flashlights, I've almost finished switching to all LiIon > batteries, mostly 18650 and 14500.   What's your experience with 14500 in single AA flashlights? Mine get hot enough with NiMH. I'm afraid to run them on 4V at 7W. Here's an example: http://www.everbuying.net/product867812.html   > be sure, but so far so good. Cheap 18650 battery capacity at 1.5A, > which is at the high end of what a flashlight will draw: > <http://802.11junk.com/jeffl/battery-tests/18650.jpg>   Lowes has a six-cell 18650 lithium tool battery for $10. Only 1.5AH, but rated for 30 Amps max. Was gonna replace NiCd in an old drill, but I'm procrastinating.     > $0.50 with many flashlight and battery combinations: > <http://lygte-info.dk/review/Review%20Charger%20Bowei%20HC-103W%20UK.html> > How customs even lets them into the country is a mystery.   I have one that looks identical except has US plug. Terminates just fine below 4.2V. Doesn't seem to have any of the characteristics shown in the review. I didn't take mine apart.

Jeff Liebermann <jeffl@cruzio.com>: May 29 07:57PM -0700 >I'd agree, but many of my devices won't run on that voltage. >Wireless power monitors and thermometers, for example.   Most everything that will run on alkaline cells will also run on LSD NiMH cells.   However, you can't just plug in a LiIon cell into a device made for alkaline cells, even if they fit. For example, if you try to replace a common AA alkaline cell with a 14500 LiIon cell, you are replacing a 1.5V cell with a 3.6V cell, which will likely burn out the device. However, you may be able to replace two AA alkaline cells with a single LiIon cell if device will tolerate a 20% increase in battery voltage. Most devices that have a voltage regulator will work nicely. Those without voltage regulators, will overheat.   >at 7W. >Here's an example: >http://www.everbuying.net/product867812.html   I don't understand. 14500 is the size of a AA cell which applies to alkaline, NiMH, and LiIon, LIPO, LiFePO4, etc, all of which have different terminal voltages. The flashlight appears to be designed for a 14500 size NiMH battery. Running it on a AA alkaline will kill the battery in short order because it can't handle the current. Running it on an LiIon battery will blow it up because it will be over twice the rated voltage. There's no information on the above web site as to whether the light is intended to operate on alkaline, NiMH, or LiIon voltages, but a comment by a user indicating that "7 days on a single AA Enelope" suggests NiMH. Do NOT install a LiIon 14500 cell as it will probably burn out the electronics (also known as the "pill").   The Cree XP-E Q5 LED is designed to operate at about 350ma and will generate about 120 lumens depending on type and bin selection: <http://www.cree.com/led-components/media/documents/XLampXPE-25A.pdf> That's about: 120 lm / (3.6v * 0.35A) = 95 lumens/watt which is consistent with todays LEDs at room temp. There is no way the XP-E Q5 LED will dissipate 7 watts or produce 600+ lumens.   In order to run on a single 1.35V nominal NiMH cell, the flashlight will require a boost converter and a current regulator. Done correctly, these work just fine. Done badly, they get hot and burn up. My guess(tm) is that this flashlight is in the latter category.   >Lowes has a six-cell 18650 lithium tool battery for $10. >Only 1.5AH, but rated for 30 Amps max. >Was gonna replace NiCd in an old drill, but I'm procrastinating.   It depends on which tool and how the conversion is done. I have several Makita 9.6v nominal power tools, that were intended to run on NiCd or NiMH, now converted to run on 11.3v (3 cells) LiIon cells. I was concerned about the increase in voltage, so I added a series power diode to drop the voltage. Works fine but admittedly does get warm when run heavily. Many LiIon (LiPo) battery packs can be discharged at 10C or more (that's 10 times the rated current in Amp-Hrs). That sets the minimum cell size to 18650, where my junk cells test at about 1000ma-hr capacity at 1.5A. 14500 would be to small. For charging, the recommended charge rate is 1C. If you plan to do this, make sure you use a LiIon/LiPo/whatever charger. I should mention that cramming 18650 cells into some battery packs is a major project. The good part is that such conversions require fewer cells. You might also consider using prismatic cells such as: <https://hobbyking.com/en_us/turnigy-1000mah-1s-20c-lipoly-single-cell.html> Make sure you leave room to let them inflate when charging.   >> <http://lygte-info.dk/review/Review%20Charger%20Bowei%20HC-103W%20UK.html> >> How customs even lets them into the country is a mystery.   >I have one that looks identical except has US plug.   Spray a little water into the charger and then measure the AC voltage between an electrical neutral wire and either battery terminal. The life you save may be your own. I stupidly bought 10 of these before I realized what a POS they were. I destroyed them before recycling so that nobody would get hurt.   >Terminates just fine below 4.2V. Doesn't seem to have any of the >characteristics shown in the review. >I didn't take mine apart.   I measured one of mine. When it got to 4.25V, I stopped to prevent destroying the battery.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Clifford Heath <no.spam@please.net>: May 30 12:42PM +1000 On 30/05/17 12:57, Jeff Liebermann wrote: > However, you may be able to replace two AA alkaline cells with a > single LiIon cell if device will tolerate a 20% increase in battery > voltage.   They even sell blank AA cells (containing a wire from +ve to -ve) for devices that can use one Li cell instead of two alkalines. I use these in an Apple Bluetooth keyboard for example.   > 120 lm / (3.6v * 0.35A) = 95 lumens/watt > which is consistent with todays LEDs at room temp. There is no way > the XP-E Q5 LED will dissipate 7 watts or produce 600+ lumens.   Except in Chinese marketing materials :)   >> Only 1.5AH, but rated for 30 Amps max. >> Was gonna replace NiCd in an old drill, but I'm procrastinating.   > It depends on which tool and how the conversion is done.   I did this with my Ryobi, and use it every day: <http://polyplex.org/electronics/ryobi_lifepo4/index.html> It used to have 11 stubby NiCD cells, now four 26550 LiIons. Recently reworked with a female balance connector, after it short circuited in a toolbox and burnt one of the wires.   > If you plan to do this, make sure > you use a LiIon/LiPo/whatever charger.   Hobbyking supplied a Turnigy Accucel-6 for $25, which runs nicely off an old laptop power brick.   Clifford Heath.

Jeff Liebermann <jeffl@cruzio.com>: May 29 09:40PM -0700 On Tue, 30 May 2017 12:42:03 +1000, Clifford Heath >> which is consistent with todays LEDs at room temp. There is no way >> the XP-E Q5 LED will dissipate 7 watts or produce 600+ lumens.   >Except in Chinese marketing materials :)   There are a few simple sanity checks for lumen claims. Unfortunately, they have to be done after you've spent the money.   1. Measure the current drain with an ammeter. Assume that initial lumens/watt luminous efficacy is about 75 lm/watt for consumer lighting including some loss through the optics. So, if your flashlight draws 1.0A at 3.6V, your flashlight will produce approximately: 1.0A * 3.6v * 75 lm/watt = 263 lumens You can also look up the specs for the LED, but that doesn't always work because some lights claim to have the latest greatest high efficiency LED, but actually use bin fallout, rejects, or counterfeits.   2. Buy a cheap lux meter on eBay such as: <http://www.ebay.com/itm/381903904643> There are better models, but this one seems to track measurements with my other more expensive meters quite well. Hang it on the wall and project a round spot on the wall with the flashlight. Measure and record the spot diameter and lux values. 1 Lux = 1 lumen/sq-meter Calculate the area of the spot in square meters. Multiply the measured lux value by the area and you have lumens. Notice that you do NOT need to record the distance between the flashlight and the meter.   Problem. The spot is not uniform brightness across its diameter. To compensate, I like to measure the hot spot at the center, half way between the center and the edge, and near the edge. I then calculate (or guess) an average lux value.   No integrating sphere or tube required.   If you want to make calculations easy, a 1 square meter circle has a diameter of 1.13 meters (44.5 in). Mark this on the wall and move the flashlight back and forth until the edges of the spot hits the marks. The lux meter will then read directly in lumens.   This measurement becomes difficult when measuring odd shaped spots, such as with bicycle and automotive headlights, but I won't go there.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

tabbypurr@gmail.com: May 29 10:56PM -0700 On Monday, 29 May 2017 22:54:20 UTC+1, (PeteCresswell) wrote: > costs, but instead whether-or-not the light works when somebody grabs it > during a power failure or something after it's been on the shelf for 3 > months.   Even cheapie rechargeable NiMH do that no problem IME, and are less likely to corrode the contacts. There might be some out there that don't, but I think that issue has been exaggerated.     NT

Jeff Liebermann <jeffl@cruzio.com>: May 29 10:16AM -0700 On Mon, 29 May 2017 17:29:44 +1000, Clifford Heath   >I don't know what frequency the PIC counter input is capable of, >but I know that the AVR counter is clocked; so you can only count >at half the CPU clock frequency. Bah, humbug.   The clock crystal is 4MHz on the old version. I can't read the numbers on the schematic of the new version. That doesn't look very promising for measuring 60MHz inputs or even with /4 at 15MHZ.     >The units I have have both pairs of protection diodes, and the inputs >are joined only at the connector. I cut the trace and soldered a bit >of co-ax onto the prescaler input capacitor.   Oh swell. So the PCB wiring might not follow the schematic. I suppose it doesn't matter since the DG MOSFET seems to be badly biased anyway.   I was having nightmares last night from thinking about this counter. Maybe I should give up while I'm still sane?   >I don't have a good RF source (yet - currently building, see >https://github.com/cjheath/AD9851LCD) so I can't evaluate the >sensitivity.   Before you reinvent the wheel, there are AD9851 based DDS generators available on eBay. <http://www.ebay.com/sch/i.html?_nkw=dds+generator+ad9851> along with the associated LCD display: <http://www.ebay.com/itm/PIC16f-Controller-for-the-AD9851-DDS-Signal-Generator-Module-/182593721953> However, those only go up to about 70MHz and the output looks distorted above 30MHz. If you're going to test the counter all the way to its rated maximum frequency (2.4GHz), you're going to need a better generator. DDS has benefits for a function generator and arbitrary waveform generator, but is limited to lower frequencies.   This looks interesting (and tempting): <http://www.ebay.com/itm/ADF4350-v4-0-137-5MHZ-4-4GHZ-OLED-display-Signal-generator-RF-signal-source-12v-/262688224985> 137.5MHz to 4.4GHz signal generator in 10KHz steps. Looks ok to about 1GHz, but drops in output and increases in sidebands at higher frequencies. Looks like the same board, but in a shielded box: <http://www.ebay.com/itm/137-5MHZ-to-4400MHZ-Signal-generator-frequency-generator-RF-signal-source-dc-12v-/271838837908> Or maybe this thing: <http://www.ebay.com/itm/0-5Mhz-470Mhz-RF-Signal-Generator-Meter-Tester-For-FM-Radio-walkie-talkie-debug-/172598060649> Or maybe something computah controlled via USB: <http://www.ebay.com/itm/RF-Signal-Generator-35MHz-to-4-4GHz-via-USB-16dBm-Plus-Features-2000-units-sold-/201929990411> Or maybe a real RF generator from HP, TEK, Fluke or others that can actually be calibrated and trusted. This is the cheapest HP I could find: <http://www.ebay.com/itm/Hewlett-Packard-hp-8656A-Signal-Generator-1-990MHz-rf-signal-generator-04-/252950700229> I have an HP 8656A but prefer to use an HP 8540B. Top right: <http://802.11junk.com/jeffl/pics/home/slides/test-equip-mess.html>                 -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: May 29 11:00AM -0700 >> The free version will do all that except edit and save the resulting >> text. For that, you need the registered version.   >I'm not sure what "standard" means.   Bad choice of words. I meant that the PDF standard: <https://en.wikipedia.org/wiki/PDF/A> includes searchable text as part of the standard. I'm too lazy to look up the chapter and verse.   >I was viewing a document full of imaged >text the other day and none of the permissions were set to preclude >anything. Yet I couldn't select any text as it had not been OCR'd.   Yep. If you scan text as a bit map image, and save it in PDF format, it cannot be text searched. You have to feed it to an OCR program, which is capable of attaching the OCR text to the PDF, save it, and then you can search.   >I assume the OCR has to be done at capture time.   No. It can be done at any time with any reasonable document. I usually make some effort to realign the text and improve the contrast to make it easier (and faster) for the OCR program to do it's thing.   >Are you saying a reader will convert images to text?   If the images look like readable ASCII characters, yes. I don't think size makes much difference, but I haven't done much experimentation into how badly I can butcher the text and the OCR will still work. I also haven't tried to edit the text after reading to correct OCR errors.   Maybe a demo will help. Note that the initial scan and file saves were done in Irfanview, while the OCR and subsequent saves were done in PDF-Xchange:   Original document scanned to JPG using Irfanview 4.44: <http://802.11junk.com/jeffl/OCR%20Demo/JPG.jpg> This is not searchable.   Same document saved to PDF using Irfanview 4.44: <http://802.11junk.com/jeffl/OCR%20Demo/PDF-no-OCR.pdf> This is also NOT searchable.   Same document in PDF-Xchange 6.0 build 322.4 after OCR: <http://802.11junk.com/jeffl/OCR%20Demo/PDF-after-OCR.pdf> This one can be searched.   PDF-Xchange screen grab showing a typical search result: <http://802.11junk.com/jeffl/OCR%20Demo/PDF-Xchange-screen.jpg>   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: May 29 11:13AM -0700 On Mon, 29 May 2017 11:00:12 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >I also haven't tried to edit the text after reading to correct OCR >errors.   Here's how to edit OCR errors using Adobe Acrobat: <http://blogs.adobe.com/acrolaw/?s=ocr+and+image+layer> I'm still trying to figure it out using PDF-Xchange Editor.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Clifford Heath <no.spam@please.net>: May 30 08:17AM +1000 On 30/05/17 03:16, Jeff Liebermann wrote: >> at half the CPU clock frequency. Bah, humbug.   > The clock crystal is 4MHz on the old version. I can't read the > numbers on the schematic of the new version.   But I don't think the PIC has a clocked counter anyhow. I assume that the AVR does it to (sometimes) avoid the need for a low-pass filter.   The xtal on mine is marked "SCK451C" and "TC,A.426", whatever that means. It was about 15ppm slow, but seemed quite stable, based on measurements taken with an HP5386A.   Quite a few people have patched in a TCXO to these units.   >>> It also shows that the gates of the DG MOSFET are >>> NOT tied together.   I don't understand why they used a DG MOSFET, nor why, since they did use one, they didn't use the upper gate for gain control. It seems they're feeding the signal into the upper gate, so won't get the best bandwidth from the cascode behaviour.   >> are joined only at the connector. I cut the trace and soldered a bit >> of co-ax onto the prescaler input capacitor.   > Oh swell. So the PCB wiring might not follow the schematic.   I haven't found the schematic of the current-manufacture.   > I was having nightmares last night from thinking about this counter. > Maybe I should give up while I'm still sane?   I think it's fixable, perhaps with an additional front-end. It would still be easier and cheaper than building from scratch.   >> sensitivity.   > Before you reinvent the wheel, there are AD9851 based DDS generators > available on eBay.   Who do you think designed those? People like me :) I have a bit of that Jedi "build your own light sabre" thing going on.   Plus there's no accessible used test equipment market here in Australia. Whenever nice gear comes up at bargain prices, merchants buy it up and slap a stupid price on it.   > <http://www.ebay.com/sch/i.html?_nkw=dds+generator+ad9851>   That's exactly what I'm using for development. They have all copied a flaw in the output filter design, leading to very low output at higher frequencies. Some impedance problem, it's not designed to drive 50ohms. I'll add a buffer.   > along with the associated LCD display: > <http://www.ebay.com/itm/PIC16f-Controller-for-the-AD9851-DDS-Signal-Generator-Module-/182593721953>   I loathe and detest both PICs and those 16x2 displays. I'm building one with 320x240 colour touch screen.   The Arduino also has TTL-level RS232, so add a $2 USB module and you have USB control.   > way to its rated maximum frequency (2.4GHz), you're going to need a > better generator. DDS has benefits for a function generator and > arbitrary waveform generator, but is limited to lower frequencies.   I expect to incorporate an ADF4351 also, and possibly two AD9851's, to give quadrature (but still cheaper than AD9854 or whatever the multi-channel DDS chip is).   E.g. <https://www.aliexpress.com/item/35Mhz-to-4-4GHz-4400mhz-PLL-RF-Signal-Source-Frequency-Synthesizer-ADF4351-Development-Board/32757566484.html>   The ADF351's have the same problem as most of those VCO synthesisers, that they won't sweep cleanly. Changing the frequency makes them jump wildly about until they stabilise again.   > This looks interesting (and tempting): > <http://www.ebay.com/itm/ADF4350-v4-0-137-5MHZ-4-4GHZ-OLED-display-Signal-generator-RF-signal-source-12v-/262688224985> > 137.5MHz to 4.4GHz signal generator in 10KHz steps.   The Arduino clone and TFT Touchscreen LCD cost me $AU14 all up. <https://www.aliexpress.com/item/2-4-SPI-Serial-TFT-LCD-Touch-Panel-240x320-Dots-5V-3-3V-Module-ILI9341-Driver/32665656357.html> Add the $30 ADF4351, a $17 $AD9851, and USB and you have a nice bundle for half what the above costs.   > actually be calibrated and trusted. This is the cheapest HP I could > find: > <http://www.ebay.com/itm/Hewlett-Packard-hp-8656A-Signal-Generator-1-990MHz-rf-signal-generator-04-/252950700229>   "Does not ship to Australia"   > I have an HP 8656A but prefer to use an HP 8540B. Top right: > <http://802.11junk.com/jeffl/pics/home/slides/test-equip-mess.html>   I have to give this HP5386A back, but not in a hurry - my friend also has mountains of test equipment. He worked in sat-comms, so has contacts who call him before dealers get there - but he loves to hoard it all :(   Clifford Heath.

rickman <gnuarm@gmail.com>: May 29 11:04PM -0400 Jeff Liebermann wrote on 5/29/2017 2:00 PM:   > No. It can be done at any time with any reasonable document. I > usually make some effort to realign the text and improve the contrast > to make it easier (and faster) for the OCR program to do it's thing.   It is so easy to be misunderstood. I'm talking about the text showing up in the PDF document. I receive d a document that was clearly a scanned image in a PDF file. But the text was selectable and copyable. The two options are the image was scanned and OCR when the PDF was made, or the PDF viewer had OCR scanning built in. Since I couldn't select the text in another scanned image PDF it must be the former.       --   Rick C

Clifford Heath <no.spam@please.net>: May 30 12:48PM +1000 > This one: http://clayphillipsracecars.com/other/150-166.pdf > This is the manual that's upside down, which I posted about.... ... > Till then, I'll read the manual. > (and wont have to stand on my head to do it).   Other people have also given you a method, but I thought it was worth mentioning that the standard OSX (Mac) Preview app does PDF natively, and it's trivial to invert, shuffle, delete, etc. Just show the page thumbnails on the left, click on one, type Command-A to select all pages, and hit Command-L twice to rotate. Command-S saves the rotated file.   You can also select and delete individual pages, re-order pages, and even drag pages in from another document. It's nice, and it's standard.   Clifford Heath.

Jeff Liebermann <jeffl@cruzio.com>: May 29 09:58PM -0700 >are the image was scanned and OCR when the PDF was made, or the PDF viewer >had OCR scanning built in. Since I couldn't select the text in another >scanned image PDF it must be the former.   The example I provided was how to do the latter. I scanned the image in one program, and added a searchable text layer with a PDF viewer.   There are scanning programs that will seem to do the process in one step such as Nuance Omnipage, Paperport, Adobe Acrobat (NOT reader), etc. To the casual user, it looks like the process is being done in one step. In reality, it first scans to a bitmap. Next, the OCR software reads the bitmap to produce the searchable text layer. It then saves the result as a PDF file. To the best of my limited knowledge, none of the available software does the OCR step *WHILE* scanning, but I might be wrong about that.   >> This one can be searched.   >> PDF-Xchange screen grab showing a typical search result: >> <http://802.11junk.com/jeffl/OCR%20Demo/PDF-Xchange-screen.jpg>   I never did figure out how to display and edit the OCR text in PDF-Xchange Editor. Looking through their feature list of other versions, it seems to be something at only the more advanced and expensive versions will do. Bummer.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

rickman <gnuarm@gmail.com>: May 30 01:00AM -0400 Jeff Liebermann wrote on 5/30/2017 12:58 AM: > then saves the result as a PDF file. To the best of my limited > knowledge, none of the available software does the OCR step *WHILE* > scanning, but I might be wrong about that.   I'm still not getting through. I'm not looking for ways to make PDF images text selectable. I'm reporting on what I saw.       --   Rick C

oldschool@tubes.com: May 29 06:52PM -0400 On Sun, 28 May 2017 18:32:59 -0700 (PDT), Phil Allison   >> What is the difference between a BASS Guitar Amp and a STANDARD guitar >> amp, as far as the circuitry?   >** Bass amps are generally simpler with no reverb, vibrato or overdrive.   Correct. None of that on this amp. But since I am not using it for guitar, I dont need that stuff.   >There are all kinds of bass amps, like there are all kinds of dogs.   >In the tube era, a bass model would normally have a slightly larger output > tranny and bigger speaker/s.   Then it's really a BETTER amp..... This one is solid state, so it's only the speaker in question. It's a small amp, so the speaker is only an 8 inch, but it has darn good sound. And I generally consider any speaker less than 12" to be a "toy". Not so with this one!

Clifford Heath <no.spam@please.net>: May 30 09:31AM +1000 >> In the tube era, a bass model would normally have a slightly larger output >> tranny and bigger speaker/s.   > Then it's really a BETTER amp.....   Sigh. A guitar amp is what it is because it makes the sound that the musician wants. Not because it has better technical specs! It's a highly significant part of the "instrument". The same is true for bass guitar amps, though usually a cleaner sound is preferred.   > This one is solid state, so it's only the speaker in question. It's a > small amp, so the speaker is only an 8 inch, but it has darn good > sound.   Bass guitar players would only use an 8" speaker for practice, and then only under duress.

Phil Allison <pallison49@gmail.com>: May 29 08:38PM -0700 olds...@tubes.com wrote:   ---------------------------   > >In the tube era, a bass model would normally have a slightly larger output > > tranny and bigger speaker/s.   > Then it's really a BETTER amp.....   ** For bass guitar maybe, otherwise not.     > small amp, so the speaker is only an 8 inch, but it has darn good > sound. And I generally consider any speaker less than 12" to be a > "toy". Not so with this one!   ** I know the " Gorilla GB30" amp you have, it is basically a toy.   Good for only bedroom use for practice.       ... Phil

Dave M <dgminala at mediacombb dot net>: May 29 01:25PM -0500 >generally been pretty satisfied with their stuff, so I was considering >this.... (Except since it's a "BID ITEM". I passed, knowing I dont >have a chance to get it on my slow internet).   I downloaded the manual for this counter, and found several things that would cause me to dislike it. The max input signal level on the normal input is 1.4V, with no attenuator or sensitivity adjustment. Another issue is the lowest frequency on the wideband input is 1MHz. To get down to the low frequencies, (below 1MHz), the signal level has to be TTL or CMOS levels. The TTL input only goes to 10 MHz, in fact, the max frequency on that input is 9.9999999 MHz. There is a note in the manual about a problem when measuring signals having a varying frequency (like adjusting a signal generator). The display freezes if the signal frequency varies by 50KHz or more between readings. To fix this, you have to turn the counter off, and hold a button down while turning it back on.   In view of all this, I would avoid this unit, however, you might not have issues with the problems.   Cheers, Dave M

oldschool@tubes.com: May 29 06:44PM -0400 >Sorry, I don't go to "tinyurl"s anymore. Post the real URL if you want anything from me.   That's not possible. Most URLs are too long and my news provider will not allow lines that long. If I break them up, then you will have copy and paste each and every line into the header, and no one will do that. (I wont). Tinyurl is the only way I can post them.   This one is an Ebay item, those sometimes are so long that if I copy them to notepad, they are 5 lines long. (Damn near a whole paragraph).   There is a way to PREVIEW Tinyurl links.

Ralph Phillips <ralphp@philent.biz>: May 29 02:40PM -0500 > Now I know why I like PDF-Xchange!   > (By the way, I'm using their "portable version"). That's the only one > that runs on both XP and Windows 98.   I'll add that if you run IRFANVIEW as your image viewer, with the plugins, you can open a PDF, rotate the pages, and save the PDF rotated.   I also use Foxit Reader; but that sucker's bloating up like a beached whale in August in Florida ...   RwP

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