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"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 31 04:20AM -0400 Jeff Liebermann wrote: > cool down slowly. I don't know if that was necessary, but it worked > every time. I'm told that two solding irons used as a tweezer also > works, but I haven't tried that yet.   How were the new caps stored? If it is where they can adsorb moisture, you can damage them with an iron that is too hot.

Andre Majorel <cheney@halliburton.com>: Mar 31 10:40AM > Sorry for the delay but I missed the followups to my comment.   Not at all. That was very interesting. Thanks Jeff and everyone.   -- André Majorel http://www.teaser.fr/~amajorel/ J'ai des vrais problèmes, vous avez des faux problèmes.

Jeff Liebermann <jeffl@cruzio.com>: Mar 31 08:34AM -0700 On Thu, 31 Mar 2016 04:20:59 -0400, "Michael A. Terrell" >> works, but I haven't tried that yet.   >How were the new caps stored? If it is where they can adsorb >moisture, you can damage them with an iron that is too hot.   Well, I must admit that I didn't take any special precautions. Methinks that the relative humidity in my office runs between 40% and 60% but is not monitored or recorded. Occasionally, it gets low enough to where static electricity becomes a problem, or high enough to where I'm rather uncomfortable, but those are rare. The caps a mix of cut tape and loose bags stored in Ziploc bags (mostly pink anti-static) and in paper coin envelopes. Nothing in hard plastic or metal drawers that might chip or crack them. Although I know that these caps make tolerable hydrometers (and microphones), I don't think they can absorb enough moisture from the air to where a steam explosion would be a problem.   I did some digging to see if humidity might be a problem in storage conditions. There were plenty of notes on how a cracked capacitor might allow water to enter the dielectric. Soft (solder) termination is the recommended fix. Some suggests pre-heating the capacitors before soldering to drive off any moisture. One demands that the caps be used within 12 months. I didn't see humidity as being a problem until AFTER the capacitors had cracked. It would take some time for the moisture to alter the capacitor characteristics. With my hand soldering technique, I managed to instantly produce shorted capacitors, which methinks was more likely due to uneven thermal expansion, than to moisture incursion.   -- 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

"Bob F" <bobnospam@gmail.com>: Mar 31 07:25AM -0700 Andy Burns wrote: >>> cleaning, then how to deal with that.?   > Is it a solid dish or a mesh one? I don't think I'd be bothered to > repair a dish unless it's something special, buy a new one for £20-30.   Or pick up an unwanted used one via freecycle or craigslist.

gehan.ameresekere@gmail.com: Mar 31 05:01AM -0700 I have an audio amplifier speaker like the one pictured in the conversion below:   http://mightyohm.com/blog/tag/wireless/   It does not work, need help in troubleshooting this one.   Disconneced AC power and connected a battery to the terminals - no sound.

gehan.ameresekere@gmail.com: Mar 31 05:02AM -0700 > http://mightyohm.com/blog/tag/wireless/   > It does not work, need help in troubleshooting this one.   > Disconneced AC power and connected a battery to the terminals - no sound.   Will post pictures

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 31 03:26AM -0400 N_Cook wrote: > Had another go at trying to find a user manual for a classic 2014, specs > yes, but no user manual to explain about that toggle switch, mute/boost > or normal/boost variants     Don't they have music stores in your country? They show you how to operate that type of equipment, over here.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 31 12:18AM -0400 > Y'know, when I was in school they gave me this test. Turns out I was in the 99th percentile in mechanical reasoning.     Only two students in my school system got every question right on that part of the aptitude tests. Myself, and a girl who like to work on cars. I also got the top scores in math and science. I only got a 90 for English. I took every math, science and shop class that they could fit into my schedule, each year. Several years later I tested out of an Electronics Engineering school while serving in the U.S. Army. I've worked with very intelligent people who only finished high school, and I've had the misfortune of working with those who can pass tests but who are so @#$%^&* stupid that they set the shop on fire with a soldering iron.

"pfjw@aol.com" <pfjw@aol.com>: Mar 30 10:35AM -0700 On Tuesday, March 29, 2016 at 5:35:00 PM UTC-4, Gareth Magennis wrote:   > I usually brush off what I can before resorting to using my lungs and > blowing off the remaining inaccessible stuff. > Trouble is this always ends up with some in my lungs and nasal passages.   I dunno - VW for years drove their window washing system from the spare tire (anyone else remember those days?). It was always a memory contest to make sure to refill the tire, or be stranded by the side of the road as the air lines often leaked. Tires were not-so-good in those days as well.   If all you need is that one lungful, consider a small portable tankless compressor ($15 at your nearest auto-supply) and a refillable aerosol can. No more than 100psi in most cases, but it would do what you lungs can do. For that matter, you could fill such a can from the tire, a double-schraeder fill fitting is cheap enough to fabricate.   Betcha if you do this, you _will_ wish for more...   Peter Wieck Melrose Park, PA

Tim R <timothy42b@aol.com>: Mar 30 10:52AM -0700 > If all you need is that one lungful, consider a small portable tankless compressor ($15 at your nearest auto-supply) and a refillable aerosol can.   Do they make those? I could fill it from a bicycle pump.

"pfjw@aol.com" <pfjw@aol.com>: Mar 30 11:23AM -0700 On Wednesday, March 30, 2016 at 1:52:14 PM UTC-4, Tim R wrote: > On Wednesday, March 30, 2016 at 1:35:34 PM UTC-4, pf...@aol.com wrote:   > > If all you need is that one lungful, consider a small portable tankless compressor ($15 at your nearest auto-supply) and a refillable aerosol can.   > Do they make those? I could fill it from a bicycle pump.   http://ecx.images-amazon.com/images/I/41atX8vvK3L.jpg   They sure do. Not much use for high volumes or high pressures, but portable and not overly expensive. The one linked is about US$18 or so. You will note that the one linked also states that it is NOT to be used as a duster. Further research will tell you that this is because there is a tendency to vastly over-pressurize if used for this purpose. Go up in price, and you can get one rated for air only.   http://www.amazon.com/Aluminum-Pneumatic-Refillable-Pressure-Sprayer/dp/B00JKED4MS/ref=pd_sim_86_2?ie=UTF8&dpID=31d3TD-aEQL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=1BJBMAA596F3ND47C2BK   Peter Wieck Melrose Park, PA

"Ron D." <Ron.Dozier@gmail.com>: Mar 30 07:52PM -0700 Way back when, maybe 40+ years ago, I was a kid and there was a CO2 tank in the junkyard. Big and heavy. You won't find tanks in the junkyard anymore because of regulations.   I pump it up to about 160 PSI with a male to male coupler. I also have a valve to safely vent it before disconnecting.   My "compressor" has a small tank and is stationary. I can fill the tank and adjust the air in the car tires, but it doesn't last long.   A compressor (reed based) used for an airbrush would work for your application.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 31 07:26AM +1100 > the closest thing to a super-conductor at any reasonable operating > temperature as exists in nature, much better than copper (or gold), > and so such fuses ought to be considered.   **Perhaps.   > (both stands included).   > But, a fuse on a $3,500 speaker?   > Wouldn't you?   **I am 62 years old. I've been listening a sound system since I built my first one at age 17. In my 20s, I purchased my first home and proceeded to assemble a sound system to please myself and my friends at various parties. It also drove my neighbours a little nuts. This is the amplifier I used to drive my KEF transimssion lines (rated at 50 Watts) at many, many drunken parties:   http://audio-database.com/MARANTZ/amp/model500-e.html   I still own the best, but no longer use it. I certainly don't operate my sound system at the kinds of levels I once did. I also use vastly more sophisticated amplification nowadays (soft clipping, soft current limiting, etc).   In my entire 45 years of listening, I only ever damaged one of the B139 drivers. The reason the driver failed was due to poor assembly at the KEF factory. So, no. I would not put a fuse on a speaker of MINE. I don't damage speakers. For all intents, I never have. For customers, the situation is different. For headbangers, I will certainly suggest the use of polyswitches or fuses, as the safety outweighs any potential downside. I would certainly not install a fuse or Polyswitch in any high end system, unless the client and I decided it was prudent. I did so with these speakers, after long consultation with a client however:   http://elac.ro/elac%20x-jet%203.jpg (exploded diagram of the mid/HF driver)   The HF element (equivalent to a Heil unit) had failed, after his children accessed his hi fi) was not repairable. A new driver had to be sourced at almost AUS$1,000.00.   So yes, I fitted Polyswitches to protect the drivers.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 30 07:00AM +1100 >> result can be very >benign. "   > They're all benign when not active. I am talking about when they are > working actively limiting current. Maybe I didn't make that clear.   **And I explained that, if the current limiting system can be kept out of the NFB loop, then it's action can be benign.     > But if I did, and there is a scheme that will limit the current > actively without that harsh distortion, show me. A model number will > do now that with the internet I can usually get a print.   **Do the analysis based on my description. I am aware of at least a dozen products where the current limiting system is not contained within the NFB loop and the result is gentle limiting. Schematics are not generally available, AFAIK.   > or something like that. Overload it and it seemed like the gain > decreased, it didn't bark at you. But it also was not all that high > end or high power.   **There you go. I know of one amp that used a simple lamp to limit current through the output stage under overload.     >> "**That is the way high quality products do it."   > At the cost of market share of course. I agree though, just build it > right and use like 12 amp speaker fuses.   **No high end amplifier uses non-linear resistors (aka: fuses) in series with speakers. To do so, would be the antithesis of high fidelity.     > HA, I remember Heathkit touted that their speaker fuses were in the > feedback loop. Actually, the audiophile crowd kinda likes them.   **Not me. Fuses should be there to prevent fires. Nothing more.       -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Mar 29 03:18PM -0700 On Tuesday, March 29, 2016 at 4:00:24 PM UTC-4, Trevor Wilson wrote:   > **No high end amplifier uses non-linear resistors (aka: fuses) in series > with speakers. To do so, would be the antithesis of high fidelity.   Please explain with other than anecdotal information. This reads suspiciously like advocating high-cost interconnects, line cords, and speaker wires....     Peter Wieck Melrose Park, PA

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 30 09:58AM +1100 >> **No high end amplifier uses non-linear resistors (aka: fuses) in series >> with speakers. To do so, would be the antithesis of high fidelity.   > Please explain with other than anecdotal information. This reads suspiciously like advocating high-cost interconnects, line cords, and speaker wires....   **Now you're being silly. Measure a fuse sometime. The resistance increases, as current increases. It acts as a non-linear resistor. The ONLY place for a fuse is before filter capacitors in an amplifier. In the DC lines, or the speaker lines, fuses introduce distortion and should not be used. This is electronics 101.   For the record:   * People using fancy power leads are deluded. The best power leads are, of course, old style captive ones. IEC connectors are convenient and stupid. They allow consumers to be conned into changing power leads needlessly. * People using *LOW INDUCTANCE*, *LOW RESISTANCE* speaker cables may not, necessarily, be deluded. Again: Electronics 101.   Here are a couple of examples why such speaker cables may be useful:   http://www.rageaudio.com.au/modules/gallery/view.php?a=Accustat&image=091027105452_accu.jpg http://www.rageaudio.com.au/modules/gallery/view.php?a=Kappa9&image=090801082656_kappa9.jpg     Never throw the baby out with the bathwater. Electronics 101.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 30 12:06PM +1100 On 25/03/2016 9:48 PM, Mark Zacharias wrote:   > Shit for brains god damn idiot. I knew better that this when I was > sixteen fucking years old!   > I'm reminded of Chevy Chase's rant in Christmas Vacation...   **I have only done once or twice, but with a couple of recalcitrant clients, I have installed Polyswitches into their equipment. Mostly speakers, but sometimes amplifiers.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Mar 30 09:30AM -0700 On Tuesday, March 29, 2016 at 6:58:21 PM UTC-4, Trevor Wilson wrote:   > ONLY place for a fuse is before filter capacitors in an amplifier. In > the DC lines, or the speaker lines, fuses introduce distortion and > should not be used. This is electronics 101.   Silver-link fuses using an eutectic formula add negligible resistance within their ratings. Nor are they cheap. As you well know, silver is the closest thing to a super-conductor at any reasonable operating temperature as exists in nature, much better than copper (or gold), and so such fuses ought to be considered.   Example: I keep speakers from a current manufacturer that would cost me well over US$7,000 to replace today. A few bucks on fuses to protect this investment is well worth it. That I researched dual-element silver-bearing fuses to minimize any downside from adding such a device makes the choice both worth it and (probably) wise. A defective amp is not likely to gradually ramp up into the speakers, it is likely to surge - at least in my experience. So, I can run the fuse very close to the overall speaker rating letting the dual-element section handle high musical peaks without sacrificing (much) protection.   Keeping in mind that as you suggest, low-resistance speaker connections are a 'good' thing, I use #12 fine-stranded (19 strands) THHN wire for speaker leads, spun in a drill to reduce capacitance does well for short runs and is remarkably cheap at ~US$0.27/foot (both stands included).   But, a fuse on a $3,500 speaker?   Wouldn't you?   Peter Wieck Melrose Park, PA

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 30 07:03AM -0500 Circa 1987   Harman Kardon HK-400XM:   Three-head cassette deck.   Intermittent failure to record on one channel. Playback fine.   Customer sent to HK twice for factory service.   Twice HK replaced the record / play head assembly. Problem persisted.   On the bench, at failure mode, discovered full peak-to-peak bias at the output of the affected channel, swamping out the audio.   Defective (intermittent coil) in bias trap. IIRC a small module.   That customer still looks me up 30 years later when he has a problem.   Couple years later, same problem on a Kenwood KX-1030. Open coil.   Over 30 years - never seen this since.     Mark Z.

N_Cook <diverse@tcp.co.uk>: Mar 29 05:58PM +0100 On 22/03/2016 14:01, N_Cook wrote: > tyres in tape decks), completes the universal rubber tool kit. > Plus remnants in pic. minimum I've "bean sliced" down to without > breaking is about 0.3mm thick.   half price Aldi , remaindered after easter now

Colin Horsley <horsley-spam@westnet.com.au>: Mar 30 08:30PM +1100 On 29/02/2016 16:14, DaveC wrote:   > (If you're just going to Google, don't bother, I've already done > that…)   > Thanks!   Try here:-   https://www.wes.com.au/mediapub/ebook/wescat2014np/#1220   Colin       --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Gunther Heiko Hagen <guntherxxx@quantserve.de>: Mar 29 10:19PM On Tue, 29 Mar 2016 11:27:28 -0400, Michael A. Terrell wrote:   > Then explain why Florida has started farming hops instead of oranges, > in many places.   For export, of course.

Phil Allison <pallison49@gmail.com>: Mar 29 11:16PM -0700 Heiko Hagen wrote:     > They don't appear to use hops for flavouring in N. America and Australia,   ** America produces 28,000 tonnes of hops per year - practically all of it going into beer. Only Germany produces more, with 34,000 tonnes.   https://en.wikipedia.org/wiki/Hops#Cultivation_and_harvest   Thing is, they probably don't use enough of it in each barrel to suit you.   Small and craft brewers generally use a lot more malt and hops per barrel than the big commercial ones.       .... Phil

Jeff Liebermann <jeffl@cruzio.com>: Mar 29 05:31PM -0700 On Mon, 28 Mar 2016 22:46:04 -0500, "Dave M" <dgminala@mediacombb.net> wrote:   >Jon,   Methinks that you mean't me.   >What are the dimensions of the light ring (ID, OD, thickness)?   ID: 60 mm OD: 96 mm (not including lock screws and power connector). Thick: 30 mm   Adjustable power supply: Model: LC-P800 Input: 90-240VAC 50/60Hz Output: 10-12VDC 750 ma Max     -- 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

"Dave M" <dgminala@mediacombb.net>: Mar 29 10:07PM -0500 Yes, Jeff, I was addressing the question to you; sorry if I was ambiguous. Thanks for the info.   Dave M     Jeff Liebermann wrote:

Jeff Liebermann <jeffl@cruzio.com>: Mar 29 07:15PM -0700 On Mon, 28 Mar 2016 22:15:42 -0500, Jon Elson <elson@pico-systems.com> wrote:   What does this suppose to mean, do, or prove? Newsgroups: Choose,an,appropriate,group,to,redirect,replies... If you want to black hole replies, just redirect to /dev/null   Newsgroup changed to: sci.electronics.design,sci.electronics.repair     >I've heard these stories a number of times. And, yes, maybe some people use >insanely hot irons or in some other way cause this problem. And, some >really large caps are prone to this damage.   Yep. As James Arthur mentioned, it's not a problem with the physically small caps, which come to a uniform thermal equilibrium rather rapidly. It's only the big caps, with lots of plates, thin low voltage ceramic dielectric, and larger thermal mass, that were a problem for me.   >But, as I say, I have hand- >soldered over 25,000 0805 MLCC caps of modest value without seeing this >problem.   One exception will break any such rule. Dig out a larger and higher capacitance MLCC cap in a 1210 or larger package. Try soldering it with a single soldering iron. Unless you're very good, it won't take much to trash the cap.   <http://www.avx.com/products/ceramic-capacitors/high-voltage/high-voltage-mlc-chips/> "Chip sizes 1210 and larger should be reflow soldered only."   >I use a very good Weller temperature-controlled iron, and run it >at a modest temperature.   I use several ancient Weller WTCP TC201 and TC202 (because they were free) soldering stations. Most of my tips are 750F with a few at 850F.   >Much better to use an iron with really good >thermal conductivity at a lower temperature than one with poor conductivity >at a very high temperature.   I don't understand. All the tips are made of plated iron. There's little difference in thermal conductivity between tips, unless you want to throw in copper tips heated with a gas burner. What part of the soldering iron varies in thermal conductivity?     -- 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

John Robertson <spam@flippers.com>: Mar 29 11:14AM -0700 On 03/24/2016 1:44 AM, Top Cat wrote: >> www.flippers.com >> "Old pinballers never die, they just flip out."   > Hi John, if I could look at what you have that might be the answer to my prayers. I can't find your e-mail though. Am I being dense? Is it glaring at me somewhere? Cheers.   Hi Chris,   I have now scanned my files and they are legible. Is there any marking on your monitor? Letter and number codes? Failing that, what is the number on the picture tube?   I scanned these as TIFs and they are huge (100mb) because they are blueprints. If anyone can convert scanned blueprints to straight B&W I would be happy to share these via dropbox.   My return email is valid! Or replace spam with jrr if you prefer.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

jurb6006@gmail.com: Mar 29 04:09PM -0700 >"I scanned these as TIFs and they are huge (100mb) because they are >blueprints. If anyone can convert scanned blueprints to straight B&W >I >would be happy to share these via dropbox. "   Pretty sure I can do that in PSP, and save them in JPG format so they aren't so huge.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 29 10:34PM +0100 "T i m" wrote in message news:3ekkfb9h7n1hagj2h45imjq8p3knmf1794@4ax.com...   On Tue, 29 Mar 2016 00:34:20 +0100, "Gareth Magennis" <soundserviceleeds@outlook.com> wrote:   <snip>   >I only want to blow dust off a heatsink. I can actually do this myself by >taking a big breath and blowing hard.   I've done that for someone on an overheating PC but using a thin tube to better direct the air and get my face out of the way. ;-)   >But I really don't want to do that, and I don't want a large compressor >plus >tank I have to store somewhere to do this for me.   I've not read the entire thread but I have a very portable and 'adequate' instant / oil-free, non reservoir compressor I regularly use for blowing out PC heatsinks and cases and have done so for many years now (to good effect).   http://nbwelly.en.made-in-china.com/product/EeyQOYrlbXWg/China-1-5HP-Oil-Free-Portable-Air-Compressor-Without-Tank.html   http://tinyurl.com/hn3xonj   My mate (who owns his own PC repair shop) has the exact same and has been using his for a similar period. The only thing against them, you do need power and they are pretty noisy (but aren't generally running for long). Personally, I leave mine just inside an external door, just close the door on the hose and blow the item clean outside (so not so noisy).   <snip>   >has the right attachment for blowing up at any local garage. >http://www.puretyre.co.uk/tyre-information/tyre-definitions/space-saver-tyre/   >I just need a smaller tank to do the same job.   As I believe has already been mentioned, you don't get a lot of 'compressed air' when you aren't compressing it to very high pressures so you may be stuck with something that is still reasonably bulky. A spare wheel may well be good enough and as you say, already has the right connections, at least for inflation. ;-)   I bought one of these to do exactly the sort of thing you were talking of:   http://www.toolstation.com/shop/Power+Tools/d40/Air+Compressors+%26+Accessories/sd3147/Trade+24L+Air+Receiver/p19659   http://tinyurl.com/zjonb68   I have to admit I've not used it yet but I hope to soon, both to expand the capacity of my small silent workshop compressor (Bambi) and to have something in the indoor workshop for the odd small blowing out job (that I can re-charge myself down the workshop on the other compressor).   Cheers, T i m             Thanks, Tim.   I was a little bit hasty in suggesting a 60 psi spare tyre might be a solution. I tried it earlier to realise the valve is just designed for slow filling, and has a very restricted airflow when deflating. (Which I knew already but just plain forgot)       Point is, it doesn't take an awful lot of air to blow dust off a heatsink. I usually brush off what I can before resorting to using my lungs and blowing off the remaining inaccessible stuff. Trouble is this always ends up with some in my lungs and nasal passages.     Cheers,     Gareth.

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Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 29 07:17AM +1100 On 29/03/2016 3:20 AM, Cydrome Leader wrote: >> back to the owner (until it did).   > It is sort of sad it can't handle that. Just a few warranty service calls > would pay for hundreds or thousands of fuse to have been installed.   **Fuses open in seconds. Semiconductors can fail in MILLISECONDS. Active current limiting is the best solution.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

jurb6006@gmail.com: Mar 28 05:21PM -0700 >"When would you use a diferent preamp, or different power amp in an >integrated unit anyways? Anything with the shunts was already packed >with >all sorts of silly inputs to start with. "   Preamps can make as big a difference in the sound as power amps. People also get to liking how they hook up, all their shit fits. They like the tone controls, and that is a big one. some of those old 25 WPC Marantzes had fantastic preamps and tuners, but now the guy went and bought some speakerzillas and needs more power. So he picks up an ampzilla somewhere but wants the rest of his system to stay the same. He likes how it looks and sounds, just needs more power.   That's why, and it really is not audiophoolery, just one of thoise things.   I had a Marantz 4270 I ran in strsapped mode for the front to get the more power (clipped at 154 watts per channel in bridged mode) and used the rear pre outs to feed a Sansui 771 into 2.3 ohms for the back which had modified speakers. They originally had passive radiators but I put speakers in there instead. Then I had to use an EQ (Soundcraftsmen PE2217) to get the sound right.   Purists can bitch and moan about using EQ like that but what about the Bose 901 ? The EQ for that has about a 30 dB range that a standard graphic EQ cannot do. So if that is OK then my system was OK.   All of this shit can sound different, so if you got a receiver or amp and like the sound, you can keep it. Also, people are getting back into vinyl and phono preamps are not all created equal. All over the place the audiophiles say my Soundcraftsmen has a shitty phono stage, that it sounds harsh. Well I never used it, I used the EQ and it is one of the best EQs I have ever seen. Uses real coils, and the way it is configured, when you get to the extremes in the ranges, they are pretty much effectively in parallel. the chip based ones cannot do that and give you camel humps in the response. I can show you on a scope with a 1 KHz square wave.   People do crazier shit than that when it comes to stereo equipment. Some go nuts and claim one speaker wire sounds better, I do not go for that. Unless the resistance is very high it makes no difference. And like the cables, RCA type, the only thing that matters in them is the capacitance per foot. A cable from a turntable with a moving coil cartridge, maybe. then you might need superior shielding. but for the rest of it, for electronic sources like a CD player or tape deck, you almost do not need shielded cables. I'll use Romex from a CD p;layer to an amp and nobody will hear the difference, or might actually think the Romex sounds better !   Learning a little bit of math and electronics makes you aware of what really matters and what does not.

jurb6006@gmail.com: Mar 28 05:39PM -0700 >"**Fuses open in seconds. Semiconductors can fail in MILLISECONDS. >Active >current limiting is the best solution. "   Yeah like when seconds count, the cops will be there in minutes. Completely true. The problem is the implementation.   Active current limiting tends to make bad bad distortion on low impedance loads. It sounds as if a speaker is blown or a woofer is bottoming out.   I have tried to figure out a better way but am at a loss on that, so I understand why they did it. It protects their product from abuse and unnecessary warranty claims. And it was cheap, couple transistors, diodes, maybe six resistors in all.   The alternative is to use a relay and a latch, which is run through the uProcessor on newer shit and it reads "Protection" on the display. I am not fond of those type of circuit because it makes it harder to troubleshoot.   I think they should make amp ready to drive one ohm loads, but then they would be more expensive and sales would be lost.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 29 02:03PM +1100 > Active current limiting tends to make bad bad distortion on low > impedance loads. It sounds as if a speaker is blown or a woofer is > bottoming out.   **Nonsense. There are several methods of implementing current limiting, which do not impact severely on sound quality. If the current limiting can be kept out of the global NFB loop, then the result can be very benign.   > harder to troubleshoot.   > I think they should make amp ready to drive one ohm loads, but then > they would be more expensive and sales would be lost.   **That is the way high quality products do it.       -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

jurb6006@gmail.com: Mar 29 09:34AM -0700 >"**Nonsense. There are several methods of implementing current >limiting, >which do not impact severely on sound quality. If the current >limiting >can be kept out of the global NFB loop, then the result can be very >benign. "   They're all benign when not active. I am talking about when they are working actively limiting current. Maybe I didn't make that clear.   But if I did, and there is a scheme that will limit the current actively without that harsh distortion, show me. A model number will do now that with the internet I can usually get a print.   I saw one, in fact owned it. But it was not DC coupled and I don't remember the model. It was a Realistic integrated amp, maybe 40 WPC or something like that. Overload it and it seemed like the gain decreased, it didn't bark at you. But it also was not all that high end or high power.   >"**That is the way high quality products do it. "   At the cost of market share of course. I agree though, just build it right and use like 12 amp speaker fuses.   HA, I remember Heathkit touted that their speaker fuses were in the feedback loop. Actually, the audiophile crowd kinda likes them.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 28 03:53PM -0400 John-Del wrote:   > Don't waste your time trying. CRTs don't short that way. If the CRT is full of air, the tube will arc loudly. You could ground the second anode cup to the metal frame and it still won't smoke the flyback. Any secondary short will destroy the horiz output or open the B+ fuse (or both) way before the flyback can smoke. If the flyback smokes, it's bad.     I used to get dead monitors from a Burroughs service tech, and some of the CRTS were shorted internally. That caused spectacular failures, when they shorted. Just because you have never seen one doesn't mean that it can't happen. These were 12" TTL input monitors for computer terminals and they had some internal welds that had failed.

jurb6006@gmail.com: Mar 28 05:51PM -0700 Shorted/leaky anode to ground (dag ground) was pretty common in 32" Sonys of a certain era. I am not sure exactly what happened to them, I know the Hstat block was built in but that is not likely to short, it would go open. (and they did not)   I am thinking some sort of problem with the glass or something. There is no path to ground except for the grounded aquadag. The ones I found shorted were still shorted when the CRT socket is removed, it was not an anode to cathode or whatever short, it had something to do with the dag.   Maybe a slight little blow hole in the glass, and a subsequent (after years) carbon track through there. And some of these CRTs tested good on a tester. Just the HV was a dead fucking short.   This is because CRT testers cannot test the whole thing. There were two types, one was an emission tester and the other a beam current tester. The emission tester was cheaper and simply measured current to G1. The beam current tester which was capable of more accurate readings measured current from G2. Some of the better testers had a function to check G3 (focus electrode) leakage but none of them stuck 20 KV on the anode. It was impractical to do that.

John-Del <ohger1s@aol.com>: Mar 29 04:18AM -0700 > Shorted/leaky anode to ground (dag ground) was pretty common in 32" Sonys of a certain era. I am not sure exactly what happened to them, I know the Hstat block was built in but that is not likely to short, it would go open. (and they did not)   > I am thinking some sort of problem with the glass or something. There is no path to ground except for the grounded aquadag. The ones I found shorted were still shorted when the CRT socket is removed, it was not an anode to cathode or whatever short, it had something to do with the dag.   > Maybe a slight little blow hole in the glass, and a subsequent (after years) carbon track through there. And some of these CRTs tested good on a tester. Just the HV was a dead fucking short.   You're right. I forgot about those earlier Trinis. I think I saw maybe 2 or 3 tops shorted in the second anode ( the ones that used the coaxial anode connector). Replace the SG613, damper diode, and 867A regulator with Sony factory parts, and they'd blow up in a split second. Still didn't damage the flyback. Later Trinitrons did not have this problem.

jurb6006@gmail.com: Mar 29 09:24AM -0700 I didn't mean those, I meant the later ones with the kamikazi power supply using I think the 2SC4834s.   If I am not mistaken, those 2SG613s mostly blew because of a drive fault. Lose the negative pulse to the gate and it stays on too long and boom.   In the earlier ones, I think the SRC (sine resonance choke) saved alot of flybacks from overload. The SRC was there to increase the efficiency of the HV rectifiers.   Talk of these Sonys brings back a memory. I was working on a stock 26" console. (you know a toilet seart manufacturer made those cabinets, the only one could meet the specs, and like three guys could sit on top of one and you can still roll it across a thickly carpeted floor) I was pulling the control unit from the front and somehow caught the CRT board and broke the neck.   I thought ih shit, there goes a couple hundred bucks, but that ain't how it is. Under warranty all you sent back was the neck of the CRT. They said to write it up as "unable to get good convergence". I almost had to laugh, with the neck broken like that, damn right I can't get good convergence. They even paid me to change it ! Well after all Sony paid them.   Really, it was dishonest but things like that happened VERY rarely.   And now I work for factory service for RSQ, which is a marketer of Karaoke machines. They are cheap Chinese or Korean built, but what isn't anymore ? They are actually modified DVD players. In the same building is a retail outlet for them and a few other things. It's like I got two jobs in one. But anyway, they do not record the serial numbers or anything. If I fix something and it breaks again nobody has any way of knowing. Also, as I pointed out to them, the customers could rob us blind if they knew.   Good old American business, but the money spends just fine.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 29 11:13AM -0400 Jeff Liebermann wrote: > cool toys and just make fun of the nerds. Then, we all grew up > together. Today, I'm being chased by about 5 women (I sometimes loose > count).     A loose count? ;-)

Jeff Liebermann <jeffl@cruzio.com>: Mar 29 08:52AM -0700 On Tue, 29 Mar 2016 11:13:48 -0400, "Michael A. Terrell" >> together. Today, I'm being chased by about 5 women (I sometimes loose >> count).   > A loose count? ;-)   Freudian slip. I'm only being chased by a few loose women. Remind me to have a talk with my proof reader.   -- 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

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 29 11:27AM -0400 Gunther Heiko Hagen wrote: > > icy cold to hide the fact that it tastes bloody awful. QED.   > > :)   > They don't appear to use hops for flavouring in N. America     Then explain why Florida has started farming hops instead of oranges, in many places.

Jon Elson <elson@pico-systems.com>: Mar 28 10:22PM -0500 Jeff Liebermann wrote:       > This is the one that I bought for my various microscopes and cameras: > <http://www.ebay.com/itm/311570447425> This still fits below the black cone of the microscope objectives, and is larger in diameter. What I made fit around the upper part of the black cone, just under the ring that holds the microscope. So, it is much less in the way of your hands, tools, etc.   Jon

"Dave M" <dgminala@mediacombb.net>: Mar 28 10:46PM -0500 Jon, What are the dimensions of the light ring (ID, OD, thickness)? Im thinking of another application for it. I asked the seller and he/she replied that all the data about the item was in the description. The only dimension that I saw in the description was the mounting diameter (61mm max).   Dave M   Jon Elson wrote:

Chris Jones <lugnut808@spam.yahoo.com>: Mar 29 09:27PM +1100 > I need to purchase a magnifier so that I'll be able to do things like replace eproms and other small SMT's. I'm not looking to do LSI's with 150 pins Etc. Just mostly smaller stuff. For instance I currently have a board that needs an 8 pin Eprom replaced. I thought that I could do it with the magnifiers I have but the stuff is Just too small. I tried using a high res TV camera with a varifocal 3.5 to 8 mm lens but it doesn't make the image large enough. I was wondering what people are using to do this. Thanks, Lenny   Nikon SMZ645/660 (used) or SMZ745 (new), on a boom (can be home made), ideally with a ring light.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 29 12:34AM +0100 wrote in message news:6845af1b-74c5-4fce-9709-80104f9d3d65@googlegroups.com...   On Wednesday, March 23, 2016 at 8:01:33 PM UTC-4, Gareth Magennis wrote:   > I don't have a Summer House.   > Gareth.   Dust + nicotine/kitchen grease/smoke/creosote = nothing what you describe could handle. Point being, as stated, what is desired is not practical, what is practical may not be convenient. FULL STOP.   Peter Wieck Melrose Park, PA           Peter I really don't think you get this at all.   I only want to blow dust off a heatsink. I can actually do this myself by taking a big breath and blowing hard. But I really don't want to do that, and I don't want a large compressor plus tank I have to store somewhere to do this for me. I'd have bought one years ago if I had wanted to do so, I have been well aware of these things for years.   Inventing reasons I need something else to shift nicotene, grease, smoke etc is not helpful. Full Stop.       By the way, I have an emergency tyre in the boot of my car, that claims it is charged to 60psi. I bet I could fit an attachment to this to provide short bursts of air that would be far more effective than anything I can do by blowing hard, and it has the right attachment for blowing up at any local garage. http://www.puretyre.co.uk/tyre-information/tyre-definitions/space-saver-tyre/   I just need a smaller tank to do the same job.       Gareth.

T i m <news@spaced.me.uk>: Mar 29 11:23AM +0100 On Tue, 29 Mar 2016 00:34:20 +0100, "Gareth Magennis" <soundserviceleeds@outlook.com> wrote:   <snip>   >I only want to blow dust off a heatsink. I can actually do this myself by >taking a big breath and blowing hard.   I've done that for someone on an overheating PC but using a thin tube to better direct the air and get my face out of the way. ;-)   >But I really don't want to do that, and I don't want a large compressor plus >tank I have to store somewhere to do this for me.   I've not read the entire thread but I have a very portable and 'adequate' instant / oil-free, non reservoir compressor I regularly use for blowing out PC heatsinks and cases and have done so for many years now (to good effect).   http://nbwelly.en.made-in-china.com/product/EeyQOYrlbXWg/China-1-5HP-Oil-Free-Portable-Air-Compressor-Without-Tank.html   http://tinyurl.com/hn3xonj   My mate (who owns his own PC repair shop) has the exact same and has been using his for a similar period. The only thing against them, you do need power and they are pretty noisy (but aren't generally running for long). Personally, I leave mine just inside an external door, just close the door on the hose and blow the item clean outside (so not so noisy).   <snip>   >has the right attachment for blowing up at any local garage. >http://www.puretyre.co.uk/tyre-information/tyre-definitions/space-saver-tyre/   >I just need a smaller tank to do the same job.   As I believe has already been mentioned, you don't get a lot of 'compressed air' when you aren't compressing it to very high pressures so you may be stuck with something that is still reasonably bulky. A spare wheel may well be good enough and as you say, already has the right connections, at least for inflation. ;-)   I bought one of these to do exactly the sort of thing you were talking of:   http://www.toolstation.com/shop/Power+Tools/d40/Air+Compressors+%26+Accessories/sd3147/Trade+24L+Air+Receiver/p19659   http://tinyurl.com/zjonb68   I have to admit I've not used it yet but I hope to soon, both to expand the capacity of my small silent workshop compressor (Bambi) and to have something in the indoor workshop for the odd small blowing out job (that I can re-charge myself down the workshop on the other compressor).   Cheers, T i m

Jeff Liebermann <jeffl@cruzio.com>: Mar 28 07:21PM -0700 On Sat, 26 Mar 2016 19:56:12 +0000 (UTC), Andre Majorel <cheney@halliburton.com> wrote:   Sorry for the delay but I missed the followups to my comment.   >> a soldering iron tip.   >News to me. In what way are multi-layer ceramic caps and >soldering irons incompatible ?   Thermal shock easily cracks MLCC caps. I learned that the hard way while fixing several Apple Mac Mini computahs, which feature a collection of MLCC on the bottom of the main board. <https://web.archive.org/web/20130606062903/http://blog.helpmymac.ru/?p=3585> The original failure mode was shorted MLCC caps caused by either thermal shock or board flex. The bad ones were easy to find with an ESR meter. However, when I tried to install replacements (and guessing the part value because Apple doesn't supply service information to non-authorized repair shops), I managed to crack and short several known good MLCC caps with a soldering iron. Having learned the lesson, I used some solder paste and a hot air SMT reflow gun to do the soldering. I also pre-heated the PCB and let the caps cool down slowly. I don't know if that was necessary, but it worked every time. I'm told that two solding irons used as a tweezer also works, but I haven't tried that yet.   You'll find some more details under: <https://www.google.com/#q=mlcc+capacitor+crack> <https://www.google.com/#q=mlcc+capacitor+soldering+iron> Lots of articles and guidelines on handling and soldering these caps, some of which warn about using a soldering iron. For example:   <http://www.vishay.com/docs/45034/soldrec.pdf> 6. Soldering with a Solder Iron Attachment by soldering iron is not recommended. A heat shock may cause a crack in the MLCC chip capacitors, however, if solder iron is used, the following precautions should be taken: ... (etc)   Damage Prevention When Soldering Ceramic Chip Capacitors <http://www.eptac.com/webinars/presentations/eptac_09_17_14.pdf> Hand Soldering - A pencil type soldering of 30 watts maximum and with a diameter of 3 mm maximum should be used. - The soldering iron tip temperature should be less than 300C [572F] and maximum contact time should be 5 seconds. - The soldering iron tip should never come in contact with the component body. Ever try to solder a small MLCC cap without touching the body with the soldering iron tip? Good luck.   <http://www.murata.com/en-us/support/faqs/products/capacitor/mlcc/mnt/0001> In order to prevent damage (cracks) to the component that can be caused by localized rapid heating and heat shock, preheat the chip, for example, to prevent it from being subjected to heat shock.   -- 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

Jon Elson <elson@pico-systems.com>: Mar 28 10:15PM -0500 Jeff Liebermann wrote:     > cool down slowly. I don't know if that was necessary, but it worked > every time. I'm told that two solding irons used as a tweezer also > works, but I haven't tried that yet.   I've heard these stories a number of times. And, yes, maybe some people use insanely hot irons or in some other way cause this problem. And, some really large caps are prone to this damage. But, as I say, I have hand- soldered over 25,000 0805 MLCC caps of modest value without seeing this problem. I use a very good Weller temperature-controlled iron, and run it at a modest temperature. Much better to use an iron with really good thermal conductivity at a lower temperature than one with poor conductivity at a very high temperature.   Jon

mike <ham789@netzero.net>: Mar 28 12:57PM -0700 On 3/28/2016 8:48 AM, Cydrome Leader wrote: > It can be impossible to get the batteries out. I had a Kel-Lite destroyed > that way. Somebody on usenet suggested wrapping the cells in saran wrap > so if they leak you can just slide the whole mess out.   That probably won't help. You have to pull them out and there's nothing to pull on. I had a maglite with that problem. I had to saw it in half to get a look at the markings on the battery. Was Duracell. Sent them a picture. They sent me the cost of the light.

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