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adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Feb 03 01:50PM > Why should someone replace ALL the capacitors on old Tube equipment?   > It seems that some people advocate that.   One of the factors that is often overlooked is the tolerance of the circuit to the various types of wear-out mechanism.   If a cathode by-pass capacitor on the sound output valve goes leaky, it would have to leak very badly indeed (and measure only a few hundred ohms) before it upset the operating conditions of the valve. On the other hand, if an inter-stage coupling capacitor begin to leak and puts even a small proportion of the anode voltage of the first valve across the grid leak of the second, it will upset the second valve very badly and may even destroy it.   Electrolytic smoothing capacitors in the HT line will leak even when brand new, but the leakage is usually fairly small once they have settled down. If they later begin to leak badly, this will cause internal heating and damage which may not be obvious - the set will appear to carry on working as normal. Eventually, when the leakage increases even more, something in the power supply will fail due to overloading or the capacitor itself bursts; but until that point, there may be no hint that things are going wrong because the circuit is reasonably tolerant of that sort of leakage.   I have repaired QuadII amplifiers which almost met specification even though the internal voltages were all over the place, most of the capacitors were leaking and some of the resistors had changed value too. The initial design was intended to be tolerant of a wide range of component values (close-tolerance components were very expensive) so it wasn't badly upset by drift due to ageing.     -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Feb 03 10:12AM -0500 On 02/02/2017 09:36 PM, Jeff Liebermann wrote: > the warranty period is deemed to be "over-designed". It is then > redesigned using lower rating or cost components so that everything > blows up at the same time. I've seen it happen.   Oliver Wendell Holmes wrote a very funny poem about that, "The Deacon's Masterpiece, Or, The Wonderful One-Hoss Shay".   Here it is, read by Eddie Albert.   https://www.youtube.com/watch?v=wiOHhhwnK6k   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

"pfjw@aol.com" <pfjw@aol.com>: Feb 03 08:23AM -0800 On Thursday, February 2, 2017 at 4:33:51 PM UTC-5, ohg...@gmail.com wrote:   Perhaps those who've restored a bunch of these can comment if they actually did dynamic testing of the capacitors.   I have done a fair number of AK55s and their Radiola and other-brand contemporaries, using potted 1 & 2 uF paper caps. I will typically test them at 500VAC on a proper full-voltage cap tester.   I have never, repeat, never found a bad potted paper cap in an undamaged device. The secret, in my opinion, is that the caps are massive (I have unpotted a couple for the sake of curiosity from rusted-out hulks), with wide clearances. The potting tar makes for an excellent seal as well.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Feb 02 10:10PM -0800 > > ** But in fact the CE brand caps are 50+ years old, dried out and > > worthless.   > In the probably vain hope that there is still a few sane neurons firing   ** FFS, you moronic fucking asshole - until you see one of the CE fakes yourself you have NO grounds to be claiming anything !!!!!!!     FYI:   The cap I opened up was labelled 4 x 20uF @ 475V.   https://www.cedist.com/products/capacitor-ce-mfg-475v-20202020-f-electrolytic   You can peel off the metallic label and see the original, stamped in markings and also a 4 digit date code, giving week and year.   The code on my example indicated manufacture in 1963.   The insides were green with corrosion and several aluminium connecting straps ware eaten right through. The core of the cap was dry as a bone.   A customer had built a clone of the Fender Princeton Reverb amp. He purchased the cap along with other parts including a stainless steel chassis from the USA.   The amp was delivered to me in May 2013 suffering from loud hum and motor boating - since none of the electros inside the can worked.   BTW:   Go fuck yourself.       .... Phil

ohger1s@gmail.com: Feb 03 04:38AM -0800 On Friday, February 3, 2017 at 1:10:32 AM UTC-5, Phil Allison wrote:   > BTW:   > Go fuck yourself.   > .... Phil   So Phil, does CE have a time machine that allows them to retrieve thousands of these same exact cans to fill orders? Maybe the cans age as they're transported through time?   Assuming you're not lying to cover your ass, did you consider that someone may have stuck the label on an old can and returned it to CE for credit? I can assure you that crap like that does happen.   I've been in the repair business for over 40 years and I've gotten "brand new" parts from reliable suppliers including OEMs that were clearly *not* new. These were either mistakenly returned for new credit or intentionally returned for nefarious reasons and ended up being restocked.

Phil Allison <pallison49@gmail.com>: Feb 03 05:06AM -0800 ohg...@gmail.com wrote:   Phil Allison wrote:     > So Phil, does CE have a time machine that allows them to retrieve > thousands of these same exact cans to fill orders?     ** There are not thousands of orders.     > did you consider that > someone may have stuck the label on an old can and returned it to CE for > credit?     ** No - that is absurd.   Old caps would have used solder lugs and bent support tags.   It's a common re-labelling scam, been going on for decades with all sorts of components including ICs, power transistors and vacuum tubes.   I bought some 22uF, 450V pigtail electros once from a local dealer that turned out to have well used 22uF, 400V radial types fitted inside the can. They looked wrong because there was black rubber at both ends of the can instead of just one end.   BTW go fuck yourself.     .... Phil

amdx <nojunk@knology.net>: Feb 03 07:39AM -0600 > However, it seems that no one sells the multi-part electrolytic > capacitors anymore. Particularly the ones on aluminum containers that > were mounted on the chassis.   Why don't you check at, > http://www.antiqueradios.com/forums/index.php A forum full of oldtimers there with lots of experience replacing old caps. Hey, and it has no bickering!   Mikek         --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Feb 03 06:00AM -0800 On Friday, February 3, 2017 at 7:38:59 AM UTC-5, ohg...@gmail.com wrote >>Stuff<<   Not to worry. Phil is reasoning from one single incident in 2013 (the Fender) to the general. My cat is grey, therefore all cats are grey (with apologies to Ben Franklin ('in the dark, all cats are grey').   Not only that, but as he did not actually purchase the offending item directly, he has no idea which bin it came from - NOS or New Stock. I can get shiny NOS caps all day at any of several local sources, all of them no better than they should be. And, if I represent them as such, I can sell them all day long to instrument amp people who have an entirely a different view of the species. I just sold a handful of very, very vintage "Black Cat" capacitors to an instrument amp neighbor for far too much $$ - he insisted - if I promised to sell him any others I might acquire as I go along.   In the unlikely event that I do purchase caps of unknown provenance, I do so face-to-face, and carry an ESR/Cap meter with me. That would be Kutztown, twice a year. Meaning - if one purchases caps from unreliable sources, one more-or-less deserves what one gets. As, the only reason to go to said unreliable sources would be "save" money. AES, VTA and those with actual reputations to support are not cheap, and do stand behind what they sell. Ah, well, perhaps Australia is the dumping ground for such.   Peter Wieck Melrose Park, PA

ohger1s@gmail.com: Feb 03 07:08AM -0800 On Friday, February 3, 2017 at 8:06:57 AM UTC-5, Phil Allison wrote:   > > So Phil, does CE have a time machine that allows them to retrieve > > thousands of these same exact cans to fill orders?   > ** There are not thousands of orders.     You know this how? Perhaps the Russians hacked CE's site and passed the info to you.   > > credit?   > ** No - that is absurd.   > Old caps would have used solder lugs and bent support tags.   .... Phil   That's true, but you didn't have the opportunity to inspect it. Here, let me refresh your memory for you:   >>**A customer had *built* a clone of the Fender Princeton Reverb amp. He purchased the cap along with other parts including a stainless steel chassis from the USA. The amp was delivered to me in May 2013 suffering from loud hum and motor boating - since none of the electros inside the can worked.   Since the amp was delivered to you already built and suffering from hum and motor-boating, you did *not* see the capacitor's lugs or twist tabs before your customer installed it. Oops....   And for you last suggestion to me, let me just say that while it's physically impossible to accomplish, it's nice to see that if nothing else, you still have your warmth and charm at least.

jurb6006@gmail.com: Feb 03 03:25AM -0800 ."The problem is that anything to do with the emission control system has to be certified to not alter the emissions of the car. Hmmm, maybe won't matter a lot on a 30 year old car (if it even HAD a computer). But, making after market replacement parts for any part of the emissions system has to go through a lot more than somebody making a wiper motor or a fender. "   Many 30 year old cars had computers. They were basic, just controlled fuel mixture and ignition timing. Actually, after studying them a bit I find that it almost doesn't matter how many cylinders there are except for idle speed. Later one fire the injectors in pairs or possibly single at a time in which case you need a cam pulse to know what cylinder you're on. Generally a ring counter and a PWM can do the ignition, and the old TBFI doesn't care. When the MPFI came out it mattered and it matters in those cars that have direct cylinder injection.   The newer ones with the transmission controlled electronically present a new challenge but it can always be turned into and "auto-stick" where you shift but it is done with hydraulic valves. One of the problems with that is the newer transmissions are too cheap and frequently lack a one way clutch for the lower forward speeds, this means that downshifing must be done at the right RPM or there is a big objectionable clunk.   But it can be done. What can't be done with any realistic expectations is to drive a plasma panel, or even an LCD panel. Someone could rig up a backlight if that happens to fail and doesn't send the thing into knipshits and subsequent shutdown. (to protect you from the mercury of course, in their lead free product)   In any event, in the end the manufacturers win, unless we speak with the loudest voices possible. It takes some balls and staying out of debt. You go tell the John Deere dealer you will not be buying as new unrepairable item and since your old item is not repairable your crop will rot. Also mention that their founder would likely be rolling over in his grave. And then, we take every Tektroix scope that runs Windows and then it crashed and is no longer supported and take it to Oregon and throw it through the biggest piece of plate glass on their building. Take your fucking junk back. This is not a smartphone, get it ? I am not a 14 year old who needs the latest technology, and BTW, get off your slimey skinflint asses and build us a CRO again. At least one model. Either non-sampling or can be switched to non-sampling. I want to slow down the sweep and see the green dot go across the screen. that is what scopes do.   I, for one, am sick of this shit.   Know what Trump can do ? Somehow make it so when something is not repairable due to parts cost or non-0availability of parts or information, the company must take it back and pay for environmentally proper disposal.   Through the nose. Oh there's mercury in there, twenty bucks. Nickel in that stainless steel ? Ten bucks, add that shit up until it is more than what the thing cost new.   I hope Trump starts drinking vodka with Putin and grows a pair. Fuck you that you bestow your factory and or dealerships on the US, you PAY for the privilege to do business here, you got it fleagle ? You don't like our taxes you go peddle your junk in fucking Indonesia or some shit because you are banned from this market. We will make our own.   no factories here, no stores here. real simple like that, or can be refined. Keep your junk. And BTW, that wheat you feed your hogs to sell that fat laden pork to USians and make us sick ? It has just doubled in price, and there is now a tariff on hog bellies that will make speculators run for the bathroom.   You wanna see hoe to fix the economy ? Well it takes someone ab0ut twice as radical as Trump. and he pissed off Australia. Know what ? I sat there earlier trying to give a fuck less but I just could not do it. They are totally irrelevant.

jurb6006@gmail.com: Feb 03 03:27AM -0800 Oops, the part I forgot to putt in :   Most cars that old are exempt, or they only have to pass tailpipe emissions. We can do that. It is the newer ones that if the god damn glove box light is out it fails that are at issue here.

"Mr. Man-wai Chang" <toylet.toylet@gmail.com>: Feb 03 08:16PM +0800 On 2/3/2017 3:11 AM, Jeff Liebermann wrote: > far, legeslation has been introduced in 6 states. Kansas, Mass, > Minnesota, Nebraska, New York, and Wyoming so far. I don't know much > more than what I've read about it:   Only big equipment can be repaired easily? Not with chips.   -- @~@ Remain silent! Drink, Blink, Stretch! Live long and prosper!! / v \ Simplicity is Beauty! /( _ )\ May the Force and farces be with you! ^ ^ (x86_64 Ubuntu 9.10) Linux 2.6.39.3 不借貸! 不詐騙! 不援交! 不打交! 不打劫! 不自殺! 請考慮綜援 (CSSA): http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

Look165 <look165@numericable.fr>: Feb 03 09:01AM +0100 It would be OK but you'd better put the 2 240 lugs in parallel on each side.   This is needed for having the maximum available power.

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