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isw <isw@witzend.com>: Jun 02 09:55PM -0700 In article <3cd7c0fd-4b5b-416b-8c1b-8433b6458b9c@googlegroups.com>, > head VCR going frame by frame you can see the effect. Two frames would be the > same and then three frames would be the same. And I am probably the only > person in the world who knows they cheated.   That's not "cheating"; it's just the standard "two-three pulldown" technique (known as "telecine") that NTSC (but not PAL) used to convert 24 FPS movies to ~30 FPS video. It wasn't frames that were repeated, though; it was fields (a "field" consists of either the odd-numbered lines, or the even-numbered ones).   If you numbered fields sequentially, it went 1-1-2-2-2-3-3-4-4-4-5-5-6-6-6- ...   Worked pretty well but added a motion artifact known as "judder" because of the irregularity. It did have the advantage of making the sound run at the proper speed (and incidentally make the movie have the "proper" running time).   PAL, OTOH, just overcranked the film from 24 to 25 FPS. The audio pitches were slightly too high, people talked slightly faster, and the film was over slightly quicker.   The 2-3 pulldown worked quite well for analog TV, but gave the MPEG folks fits until they finally realized what was messing up their encoding efficiency. MPEG encoding is all about finding regularities and exploiting them, but:   If you take that field sequence 1-1-2-2-2-3-3-4-4-4-5-5-6-6-6- ...   and show it with the associated film frames: 1-1-2-2-2-3-3-4-4-4-5-5-6-6-6- ... A-A-B-B-C-C-D-D-E-E-F-F-G-G-H ...   You see that once in a while a frame (e.g. "C") consists of two fields *not* from the same frame, but from adjacent ones. This really messes with the correlation between odd and even lines that makes MPEG work well. Worse, if there is a scene change just at that point, the odd lines and even lines are from totally different images.   The MPEG guys finally figured out that the best thing to do was just reverse the whole process (inverse telecine) to get back to 24 "proper" FPS with no irregular pulldown and no split frames, and then encode that.   Isaac

John Larkin <jjlarkin@highlandtechnology.com>: Jun 02 12:54PM -0700 >nothing more than generate heat which heats up the separate mechanism that >opens N.C. contacts?   >Thanks.   Measure the resistances!     --   John Larkin Highland Technology, Inc picosecond timing precision measurement   jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

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DaveC <not@home.cow>: Jun 01 08:38PM -0700 http://imgur.com/yIx0dC6   Original on the left, purchased replacement on the right.   Questioning whether these are equivalent for an old General Electric motor starter overload (CR106).   Seems like slightly different approaches to get a bimetalic bend effect when a specified current flows through each of these. One requires a resistance wire to heat the metal, whereas the newer one incorporates the resistance in the metal? Is that what's happening?   Does the element do the physical "tripping" of the OL, or do these do nothing more than generate heat which heats up the separate mechanism that opens N.C. contacts?   Thanks.

Ralph Mowery <rmowery28146@earthlink.net>: Jun 02 12:08AM -0400 In article <0001HW.1CFFE1A000174A8F114D213CF@news.eternal- september.org>, not@home.cow says... > nothing more than generate heat which heats up the separate mechanism that > opens N.C. contacts?   > Thanks.   All they do is generate heat. The part that is heated is in the block those things go in. That is where the actuall tripping goes on. It trips a small switch and if you look at the block they go in you will see the screw terminals for the actual switch. If you could turn them so they are outside the block, nothing would actually be heated and the switch would never trip.   If you look at the bottom of them, near the screw holes you will see a set of letters and numbers. That tells the rating of the heater (a chart will show the current range the overloads will trip at).   I think you will find that you have 2 that are of greatly different current ranges. The one with the wire is a much smaller current rating than the large flat one.

DaveC <not@home.cow>: Jun 01 11:13PM -0700 On 1 Jun 2016, Ralph Mowery wrote:   > I think you will find that you have 2 that are of greatly different > current ranges. The one with the wire is a much smaller current rating > than the large flat one.   You are correct! (c;   With the wire: 5.46A; without: 19.8A.   So they are compatible (will work in the same OL)?   Thanks.

Ralph Mowery <rmowery28146@earthlink.net>: Jun 02 10:01AM -0400 In article <0001HW.1D00060A001FD374114D213CF@news.eternal- september.org>, not@home.cow says...   > You are correct! (c;   > With the wire: 5.46A; without: 19.8A.   > So they are compatible (will work in the same OL)?   The main overload block is made to take a wide range of the heaters. It has been a while ( I retired about 4 years ago) but I think there were atleast 2 to 5 sizes of the GE overload blocks. The heaters from one size will not fit the other sizes. Each block will hold a lot of different size heaters.   The way they are most often uses is that you have the motor starter (relay) mounted vertically and the heater block is attached just under it. The heater goes from the bottom contacts of the starter through the heater and then out to the motor (load). You install the heater to match the current of the load.   The heater heats up something in that block that trips a switch in the block. That switch is in series with the motor starter coil and the stop/start switches and only carries the small current that activates the coil. Most often the motor will be 480 volts 3 phase and the voltage for the coil and switch will be 120 volts.   While the numbers I am giving out are made up as I don't want to look them up, you may have a size 1 starter rated from 1/2 amp to 30 amps, a size 2 rated from 20 to 50 amps, and so on. You install the heaters in that range to match the load.

jurb6006@gmail.com: Jun 02 02:56AM -0700 Good that you recognize that as cascode. I've ran into techs all over the place who have no clue what that is and think you are making a mistake and mean cascade. (as of now I can tell you my spellcheck does not now WTF cascode is)   Anyway I had to pull the Tek off the bench for a bit to do a Luxman R-117. Healthy receiver really. Thought maybe it was BFC but it's 160 a channel and built for it. But I am back on it next time I go down there.   But anyway, that is pretty much the word - cascode. Used to get the maximum voltage gain.   Usually it has a very high output impedance but they way they got it the transistor is just pulsed I think. It is like Q 4565 is used as a comparator. It would have to be because it appears to feed the R/C network created by the time/div switch.   The more I work on Teks, the more I am impressed with their designing skill. I have never seen anything like it, it is almost scary. Like now, I am going to look into whatever specs I can get on Q 4565 before I just stick something in there.   I got a 561A that was built before I was born and the technology in it is amazing. I got the good plugins for it too, dual time base and dual trace. And almost all tube. In fact I think it may predate tunnel diode triggering. I mean, it may predate tunnel diodes :-)   And mine has a very strong CRT with no screen burn at all.   Anyhow, I think the main thing I need in this transistor is high gain. Voltage and current requirements are minimal. Frequency response should not be much of a problem these days. Since all it does is pulse, even if the ft of the replacement is up in the gigahertz there should be no problem.   I'll keep y'all posted.   And thanks.

JC <Chipbee40_SpamNo@yahoo.com>: Jun 02 08:55AM -0400 > Anyway, since the intensify function works off the ten turn pot pretty much correctly, but the intensified part never ends of course because B sweep doesn't start, that localizes the problem. Like I said, Q4565.   > Thanks...   > Now I just hope that fucker ain't germanium !   this might help you :   http://www.reprise.com/host/tektronix/reference/transistor.asp   2n918

"None" <none@nospam.org>: Jun 01 06:28PM -0400 <thekma @ gmail.com > wrote in message news:9ce88f9c-bdbd-4afd-a94c-a30fc847c862@googlegroups.com... >>what it is sent. "   > "Why wouldn't they send it ? "   > sigh... Simple:   Not as simple as you say.   > The color gamut triangle of > the ATSC *standard* - what the STANDARD > is capable of reproducing -   ATSC has no standard color gamut. Even with caps-lock, there is no STANDARD color gamut in ATSC. Rec. 709 is common for HD programming, and Rec. 601 is common with SD. But ATSC doesn't care; the primaries and the white point are specified in the stream. Maybe someday Rec, 2020 will be standard in a future version of ATSC, but for now, there is no such thing as an ATSC standard color gamut.

thekmanrocks@gmail.com: Jun 01 07:22PM -0700 .... wrote: "STANDARD color gamut in ATSC. Rec. 709 is common for HD programming, and Rec. 601 is common with SD. But ATSC doesn't care; the primaries and the white point are specified in the stream. Maybe someday Rec, 2020 will be standard in a future version of ATSC, but for now, there is no such thing as an ATSC standard color gamut. - show quoted text -"   Butt the f out!   Find someone worthwhile to stalk. Like someone you actually know.

"None" <none@nospam.org>: Jun 01 10:40PM -0400 <thekmanrocks@gmail.com> wrote in message news:66cb8f8a-c517-49c9-8baf-4f2e29aea8d5@googlegroups.com...   > Butt the f out!   > Find someone worthwhile to stalk. > Like someone you actually know.   Sorry to disturb you with the simple facts concerning color gamuts in video standards. But there is no ATSC color gamut standard. NTSC has a very broad gamut, but NTSC is dead. Pointer's gamut is probably adequate for practical use. But ATSC doesn't care. It expect the primaries and white point to be specified in the stream; it's doesn't define them as a standard.   You are obviously way too smart to understand that. Primary colors. White point. Pretty simple stuff.   HFCUIS. LKF. FCK,WAFA. AASBDF. OK, li'l buddy?

isw <isw@witzend.com>: Jun 02 12:35AM -0700 In article <6f135efd-c02a-413c-bfcd-f9aab8a188cc@googlegroups.com>, > burst or even make the PLL in the TV have a phase error because part of the > burst is cut off. However it happened, you sometimes needed to adjust the > tint in the old days.   The Phase Alternation dropped the lowest interlace rate from NTSC's ~15 Hz to ~6.25 Hz, which is really visible and was responsible for PAL's well known "high brightness flicker".   > Also, PAL was more lines. I think it was 50 Hz which would mean they needed a > longer persistence phosphor. Also the horizontal rate was faster. They had > quite a bit more resolution bt at the cost of frame rate.   Higher spatial resolution, lower temporal resolution. Probably a wash.   > But that can be dealt with, you know movies in the theaters only used to be > 24 frames per second right ?   Actually, 48 FPS as projected -- each frame was shown twice.   > Well people did not really have a problem with > that. They only reason it is a problem with a CRT is because the picture is > drawn in a series of lines and that makes it more visible.   It's actually just because it's a much lower rep rate. See my comment on PAL's interlace problem. A longer persistance phosphor would have helped the flicker problem, but would have caused motion blur.   Isaac

jurb6006@gmail.com: Jun 02 02:33AM -0700 >"Actually, 48 FPS as projected -- each frame was shown twice. "   Didn't know that. Makes sense though.   I busted "them". I believe it was a commercial for a Sharp camcorder with good low light capabilities. They were showing what was ostensibly some kids birthday party or something. Well back then I always had six or seven head VCRs. I could tell when they pulled it down from the 48 Hz to 60 Hz. They showed each from twice but every so many cycles they would show it thrice.   The video the showed was clearly on film because a camcorders does not use 24 FPS. (or 48)   Nothing happened, WTF. I didn't buy one, I didn't initiate a class action lawsuit, in fact it is almost like who cares.   Like now, I work on "pro" audio. Know what "pro" actually means here ? It means that the FTC and IHF standards do not apply. You got an amp the has 55 volt rails which yields about 100 WPC but they can call it 3,500 watts. Technical Pro is one of the worst offenders but I have seen worse. I saw one amp supposedly 1,000 watts that had a single TO-220 type chip output. There is no way this thing was even 100 WPC.   But anyway, it is not the same with a DVD, with a good four (plus two audio) head VCR going frame by frame you can see the effect. Two frames would be the same and then three frames would be the same. And I am probably the only person in the world who knows they cheated.   Technically, if their camcorder would work in as low light as that film it was not false advertising, and I really don't recall them saying the video was taken with their camcorder. But the implication was pretty strong. Come on, they are advertising a camcorder with good low light sensitivity, What does the viewer think when he sees a kids birthday party ?   Just another example of the shit they can get away with. But the bottom line is I am so close to not giving a shit I can smell it.

Danny DiAmico <dannydiamico@yahoo.com>: Jun 01 10:35PM The rebuilt motor control board is still working great. So, the solution when you have the F28 communications error is to check the blue wires between the computer control unit and the motor control unit and to check the motor control unit for black burnt spots.

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jurb6006@gmail.com: May 31 11:03PM -0700 >"Do you have waveform 73 on schematic 8? That is the B start gate. >Start there."   I have a square wave there that tracks the A sweep speed. However I see a flat line on the collector and emitter of Q4565. That makes it highly suspect.   I have to set it aside for a minute because I have a custom customer in tomorrow. But in the meantime I can figure out a decent replacement for Q4565. It is not that critical but I do have a little bit of respect for people who are that anal about designing.   Anyway, since the intensify function works off the ten turn pot pretty much correctly, but the intensified part never ends of course because B sweep doesn't start, that localizes the problem. Like I said, Q4565.   Thanks...   Now I just hope that fucker ain't germanium !

jurb6006@gmail.com: May 31 11:12PM -0700 >"**The 465B is a great old 'scope, BUT, like many Tektronix 'scopes >of the time, tunnel diodes are used in the sweep systems. The tunnel >diodes used are VERY hard to source. "   True, and tunnel diode triggering was the best. The thing would almost sync to white noise. My old 422 was that way. And played guitars and organs n shit into it and it always synced up, no problem. Even the human voice. Even most integrated program material (songs already recorded for those who do not know the phrase).   So, when I find something looks right for Q4565 I'll let you all know if it worked.

jurb6006@gmail.com: May 31 11:20PM -0700 > Uh-Oh. Something happen to Yanik?   > Mark Z.   I think so, life. I think if he is alive now he is probably about 98 years old.   I would have liked to have met him and had a couple brewskis. I mean really, and you might as well know that I have no desire to meet any President of the US within my lifetime, and then some.   Yanik was super sharp with scopes. You ask a question and he says "that is a 100K ceramic, R401 which is on the left side behind the big blue thing in the middle of the board". Some shit like that.   I got that good with TVs but they don't go for ten grand.

"tom" <tmiller11147@verizon.net>: Jun 01 03:13AM -0400 <jurb6006@gmail.com> wrote in message news:7625ab4c-3522-453d-84c2-acd4cf3a48aa@googlegroups.com... >"Do you have waveform 73 on schematic 8? That is the B start gate. >Start >there."   I have a square wave there that tracks the A sweep speed. However I see a flat line on the collector and emitter of Q4565. That makes it highly suspect.   I have to set it aside for a minute because I have a custom customer in tomorrow. But in the meantime I can figure out a decent replacement for Q4565. It is not that critical but I do have a little bit of respect for people who are that anal about designing.   Anyway, since the intensify function works off the ten turn pot pretty much correctly, but the intensified part never ends of course because B sweep doesn't start, that localizes the problem. Like I said, Q4565.   Thanks...   Now I just hope that fucker ain't germanium ! +++++++++++++++++++++++++++++++++++++++++++   No Ge transistors in the 465. It's late. I'll look at it tomorrow and suggest a next step sans you fixing it.

jurb6006@gmail.com: Jun 01 12:30AM -0700 Thanks. I actually just checked it real quick with the scope but did not pay alot of attention to the DC levels. I actually don't even know the pinout yet.   But I got square waves on one pin the the on/off time varies with the ten turn pot on the front panel for delay. That puts the problem right there, I should be able to smell it.   If the circuit works they way I think, which is they are feeding the emitter of Q4565, I do not like that. I mean I think it is bad because of the readings, but I think it went bad because of the way they used it.   But really, they probably had no other choice. I have seen it before, I have done failure mode analysis. And I have found that at times, they simply had no other choice and their circuit was going to beat on this certain part.   So anyway, what to put in there. I am not going to pay eBay $37 for a 11132-0002-1005 transistor, even if it is in original packaging. (I made the number up so don't bother)   It is pretty much a common base amp, but not really used linear, I THINK. No, I am pretty sure. You see the base hard biased by the two 1K resistors making the base voltage -4 volts. And it says right there that -3 volts starts B sweep.

M Philbrook <jamie_ka1lpa@charter.net>: Jun 01 11:00AM -0400 In article <ab963de2-eca4-403c-8808-65d0f95c82a7@googlegroups.com>, jurb6006@gmail.com says...   > But really, they probably had no other choice. I have seen it before, I have done failure mode analysis. And I have found that at times, they simply had no other choice and their circuit was going to beat on this certain part.   > So anyway, what to put in there. I am not going to pay eBay $37 for a 11132-0002-1005 transistor, even if it is in original packaging. (I made the number up so don't bother)   > It is pretty much a common base amp, but not really used linear, I THINK. No, I am pretty sure. You see the base hard biased by the two 1K resistors making the base voltage -4 volts. And it says right there that -3 volts starts B sweep.   They sometimes do that to isolate the voltage levels on the collector side and keep the switching polarity the same. Its a faster switching method if you have a HV side verses low voltage side rather then adding a inverter stage. CaseCode config..   I am only going by your description..   Jamie

Jeff Liebermann <jeffl@cruzio.com>: May 31 08:17AM -0700 On Mon, 30 May 2016 22:20:43 -0700 (PDT), curls <borskyc@yahoo.com> wrote:     >> Most common problem I've seen on vehicle CD players is "smoke" on the >> lenses and mirrors.   >It's 2012 Mazda 3 iGT Hatch.   My point is that the drive is NOT easily replaced. No clue on parts but unless the CD drive mechanism can be identified, finding replacement parts is going to be difficult.   Read the repair faq section on "CD players in vehicles".   >I know this car was a smoker's before me for 4 years.   Bingo. 90% rubbing alcohol works well to remove the tar.   >So if most of the time problems have been smoke on the lens, do you >mean actual smokers? It'd been hopeful for me, if that's the case.   Yes, but there are plenty of other sources of oil, grease, tar, soot, and such. Just look at the windows. Do they remain perfectly clear when you're driving? Of course not. Well, some of that also gets into the CD player and makes the optics looks much like your windshield.   >Can you see in the photos, where the glass mirror would be?   I have no idea. The photos are too small and cover too large an area. Look for something like this: <http://g01.a.alicdn.com/kf/HTB1Cm2ZKXXXXXXWXFXXq6xXFXXXJ/Original-Replace-For-font-b-Pioneer-b-font-DEH-P7400MP-font-b-CD-b-font-font.jpg> The mirrors are behind the lens. <http://hyperphysics.phy-astr.gsu.edu/hbase/audio/cdplay.html>   >take a photo since it has to be in the box, where the beam isn't >directly visible. Maybe the more cleaning that I've done >will do the trick.   I don't take a photo. All I do is check if there's anything coming out of the laser or if it looks wrong. <https://www.youtube.com/watch?v=Df70YVAg-iI> Fast forward to 2:10 for what it looks like. Not all digital cameras can see 780nm light. (DVD are 650nm and BluRay are 405nm).   There are also photo diodes on a stick that can be used to measure the laser output. For some odd reason, I can't find the magic buzzwords and URL. Anyone?   Oh crap. Power outage... save, post, and run...     -- 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

dplatt@coop.radagast.org (Dave Platt): May 31 01:17PM -0700 In article <2017a819-60e3-44a8-9fa9-8172b8dc4afc@googlegroups.com>, >> In article <edc77ec8-cedd-4e17-b1f8-7c0c9da95b93@googlegroups.com>,   >Wow Dave, thanks for all the ideas!   >Any idea in brick and mortar where I can buy 99%?   I usually get it at Fry's, in the electronic-tools section.   Online... Amazon or eBay would probably work. >I'd also like to find something that won't leave lint like a qtip has.   There are foam-tipped swabs (look a bit like Q tips on steroids) designed for just that purpose.   >I had no idea CD books are done with a less expensive method similar to >home burned.   These days, burning is used for a lot of smaller CD production runs. I haven't priced things lately but I suspect it's more economical for any single-run batches of less than a thousand copies.

"Ian Field" <gangprobing.alien@ntlworld.com>: May 31 10:20PM +0100 "curls" <borskyc@yahoo.com> wrote in message news:edc77ec8-cedd-4e17-b1f8-7c0c9da95b93@googlegroups.com... > get the radio out of the car, and opened it until I can now see the laser > lens.   > I plan to clean with Qtip and isopropyl alcohol 91%.   You can get a lens cleaning disk with a small tuft of brush on it that wipes the lens as it goes round. There's normally a bottle of cleaning fluid supplied in the box.   Attacking the lens with a Q-tip is the last resort, the lens mount is very fragile. normally that is only necessary if you're a heavy smoker and tar deposits have contaminated the deck.   The Q-tip is pretty much the kill or cure last ditch attempt to save it!

Michael Black <et472@ncf.ca>: May 31 05:55PM -0400

Jeff Liebermann <jeffl@cruzio.com>: May 31 02:55PM -0700 On Tue, 31 May 2016 12:51:28 -0400, Ralph Mowery >in some open containers (about half a teaspoon) and kept checking on it. >The 90% still had something left in it after all the 99% was gone or >almost gone.   Got a proof and tralle hydrometer? Surely a well equipped kitchen laboratory should have one[1]. If not, check for home moonshine making kits online. They're calibrated in percent alcohol. You want one that goes to 200 proof (100%) alcohol: <http://www.ebay.com/sch/i.html?_nkw=proof+and+tralle+hydrometer> The following look good because of the expanded 70% to 100% range: <http://www.ebay.com/itm/New-3pcs-Vinometer-Proof-and-Tralle-Hydrometer-Alcohol-meter-0-100-w-Hydrometer-/171952516675> <http://www.ebay.com/itm/PROOF-AND-TRALLE-60-100-HYDROMETER-MEASURE-ALCOHOL-CONTENT-OF-DISTILLED-SPIRITS-/111409214376> <http://www.banggood.com/3PCSSET-Alcohol-Meter-Hydrometer-Wine-Measuring-Instrument-Vinometer-Thermometer-p-1036683.html> Note that these are all calibrated at some specific temperature. Have a thermometer handy and make sure you get the necessary temperature conversion tables.     [1] Impress your friends and relatives by measuring the alcohol concentration of their booze.   -- 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 31 03:01PM -0700 On Tue, 31 May 2016 22:20:00 +0100, "Ian Field"   >You can get a lens cleaning disk with a small tuft of brush on it that wipes >the lens as it goes round. There's normally a bottle of cleaning fluid >supplied in the box.   Ahem. I once bought one of those, stuffed it into a working CD player, and in no time produced a non-working CD player. The base of the brush, where it attaches to the CD disk, is rather hard and stiff. It hit the lens, mangled the springs, and killed the head assembly. Not recommended.   -- 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

dplatt@coop.radagast.org (Dave Platt): May 31 03:37PM -0700 In article <d82skbtde1oj7vgichdhhfruabjco6sdj1@4ax.com>, >the brush, where it attaches to the CD disk, is rather hard and stiff. >It hit the lens, mangled the springs, and killed the head assembly. >Not recommended.   Agreed. I've mostly heard horror stories like yours, leavened with a smattering of "just didn't work" or "didn't help".   I prefer a photographer's lens brush (the puffer-bulb type) as the bristles are long and soft, and will remove most dust without abrading the lens or stressing the lens mechanism. In many cases this will be all that's necessary.   A soft artist's brush moistened with isopropyl or a plastic-safe water-based surfactant is a decent choice for wet-cleaning, if that's necessary.   The difficult case is if the CD player has been exposed to tobacco smoke (and I suspect cannabis smoke is about as bad). Tobacco-smoke tar is pernicious: it gets into almost everywhere and forms a nasty film on the surfaces it touches. From what I've heard it will even get into plug-in connectors and can cause the contacts to become intermittent with time.   Light dusting won't touch it, and I don't think isopropyl alcohol will dissolve it. Consumer Reports uses it as their "difficult to remove" surface contaminant when testing things such as window-cleaning fluids. I'm not sure it's possible to get it off of CD-player lenses without the use of damaging detergents and/or scrubbing.   Years ago I loaned a prized LP to a college acquaintance, who played it a couple of times at a party where people were smoking (various substances). The LP was ruined - the surface noise level went through the roof and I was never able to get it clean again.

Jeff Liebermann <jeffl@cruzio.com>: May 31 06:46PM -0700 On Tue, 31 May 2016 15:37:53 -0700, dplatt@coop.radagast.org (Dave Platt) wrote:   >surface contaminant when testing things such as window-cleaning >fluids. I'm not sure it's possible to get it off of CD-player lenses >without the use of damaging detergents and/or scrubbing.   I've successfully cleaned tobacco tar off of electronics, including CD and DVD lenses. A few years ago, I given an 24" LCD monitor that was previously owned by a major producer of tobacco smog. It was free and all I had to do was make it work. It lit up, but almost every control and feature had something odd about the way it worked. Some of the connectors were intermittent. Initially, I didn't know that tobacco tar was the problem because the outside of the case was totally clean. However, when I tore it apart, the problem was obvious. The paper towels I was using to wash off the brown scum were gross, disgusting, and smelled really bad. I had to move the project outside for fear of contaminating the office.   After several half hearted attempts to clean it with 91% alcohol and an assortment of stiff paint brushes, I decided that I needed to do something more drastic. I removed the LCD panel assembly and cleaned it separately with alcohol, brush, sponge, and more paper towels. The rest of the monitor was immersion baptized in a mixture of 2 gallons of alcohol (at $15/gallon from the local cleaning supply house), some water, some Simple Green, a few drops of Photo-Flo, and about 10ml of paint thinner. I put the cleaning solution in a plastic washing basin, dumped various pieces of the monitor into the basin, and watched it turn slowly brown. Yech. Afterwards, I parts another rinse, this time in 91% alcohol without the other stuff, and blew off the excess solvent with compressed air. I was later able to recover about half the alcohol through distillation.   I would normally not spend that much time and money fixing a $350 (at the time) monitor, but I wanted it for myself, so profit was not an issue. At todays prices, I don't think I would do all that again. The good news is that it worked the first time when reassembled, and I'm still using it today.   >it a couple of times at a party where people were smoking (various >substances). The LP was ruined - the surface noise level went through >the roof and I was never able to get it clean again.   Alcohol should have worked. I've had some of mine cleaned in an ultrasonic cleaner, which worked well. <http://klaudio.com/kd-cln-lp200-lp-vinyl-record-ultrasonic-cleaner-dryer> or do it thyself: Ultrasonic Record Cleaner - Vinyl Clean <https://www.youtube.com/watch?v=9WgVL5lhHYU> Note that the cleaning solution is mostly soap and water (for producing the required cavitation) and a little alcohol to break loose the tobacco tar. Try not to get the label wet as the hard glue used (and the solvent) will break loose the glue. I'm sure there are more tricks, but since I didn't do the work, I'm not familiar with the details.   -- 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

thekmanrocks@gmail.com: Jun 01 05:58AM -0700 On Tuesday, May 31, 2016 at 7:08:06 PM UTC-4, Dave Platt wrote: > it a couple of times at a party where people were smoking (various > substances). The LP was ruined - the surface noise level went through > the roof and I was never able to get it clean again.   __________   Put glue on it.

thekmanrocks@gmail.com: May 31 11:12AM -0700 isw wrote: "In article <f98233c5-9087-46e8-9e87-149ee79955d2@googlegroups.com>, > captioning, ghost cancelling reference and who knows what else.   > Man's innate lust to cram as much as possible into any given bandwidth.   > With TV, they wasted it.   Actually, NTSC color makes pretty good use of bandwidth when you're constrained to all-analog, vacuum-tube technology. When it was introduced, compatible color was right at the cutting edge of (or maybe a bit beyond) technical feasibility for commercial (not to say consumer) electronics.   Isaac "   And ATSC 1.0 color gamut is actually a hair smaller than that of the NTSC it replaced.

jurb6006@gmail.com: May 31 04:28PM -0700 >"And ATSC 1.0 color gamut is actually a hair smaller than >that of the NTSC it replaced. "   You lost me there, what do you mean by that ? The different broadcasting format should have nothing to do with the colors that can be displayed, that is a function of the panel, or CRT. (actually a plasma panel is like a CRT in a way but it just has multiple rays)   Now LCD panels might be limited by the backlight. They cannot display any color that is not in the spectrum of the backlight. Actually they could not handle the colorimetry required for LED backlighting until recently when the new generation of LEDs cam out that actually have a phosphor.   Older LEDs had very spikey outputs. If a color isn't there you must display two colors opposite the wavelength you want in the right proportion so the eye mixes it. It was just too much to deal with so they went with the CCFLs.

thekmanrocks@gmail.com: May 31 05:13PM -0700 jurb...gmail.com wrote: "You lost me there, what do you mean by that ? The different broadcasting format should have nothing to do with the colors that can be displayed,"   To the contrary. A display may be capable of limitless color and dynamic range, but it can reproduce only what it is sent.

isw <isw@witzend.com>: May 31 09:14PM -0700 In article <58c7e2a0-382c-4138-9652-41cf6864c633@googlegroups.com>, > >a bit beyond) technical feasibility for commercial (not to say >consumer) > >electronics."   > Actually it could not be beyond since it worked.   What I meant was that it worked a lot better in the lab when being tended by skilled technicians that it did in domestic homes when not being tended at all. It was somewhat "drifty" and needed a lot of tweaking.   > edge. Color TV is one of the few things the US can claim as its own > invention. Other countries came later, albeit with better systems, but I am > pretty sure we were first.   If you're talking about PAL, which came later, quite good arguments can be made that it's not better at all; just that its weaknesses are in different places.   Isaac

jurb6006@gmail.com: May 31 11:39PM -0700 >"If you're talking about PAL, which came later, quite good arguments >can >be made that it's not better at all; just that its weaknesses are in >different places."   Well for one they eliminated the phase control. On US sets it was called the tint or hue control and it shifted the phase of either the chroma subcarrier or the oscillator. Their little scheme cancelled out the errors, which were mainly caused by poor frequency response which would shift the phase of the burst or even make the PLL in the TV have a phase error because part of the burst is cut off. However it happened, you sometimes needed to adjust the tint in the old days.   Also, PAL was more lines. I think it was 50 Hz which would mean they needed a longer persistence phosphor. Also the horizontal rate was faster. They had quite a bit more resolution bt at the cost of frame rate.   But that can be dealt with, you know movies in the theaters only used to be 24 frames per second right ? Well people did not really have a problem with that. They only reason it is a problem with a CRT is because the picture is drawn in a series of lines and that makes it more visible. A film projector is a whole different animal than a TV set.

jurb6006@gmail.com: May 31 11:40PM -0700 >"To the contrary. A display may be capable of limitless >color and dynamic range, but it can reproduce only >what it is sent. "   Why wouldn't they send it ?

thekmanrocks@gmail.com: Jun 01 04:06AM -0700 >"To the contrary. A display may be capable of limitless >color and dynamic range, but it can reproduce only >what it is sent. "   "Why wouldn't they send it ? "   sigh... Simple: The color gamut triangle of the ATSC *standard* - what the STANDARD is capable of reproducing - is a tad smaller than that of NTSC.

Black Iccy <Daedelus@whereamIinvalid.com>: Jun 01 11:16AM +1000 >speakers, headphones, even if I'm >listening through those dreaded Apple >Buds that ship with every iPod.   Oh I know exactly what you're trying to achieve. "In the old days" there were two main approaches. (1) Tone controls with variable 'knee' frequencies. (2) Variable 'effectiveness' loudness compensation. Twin-T passive filter would be best for your case, cheapest and easiest to build anyway.

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