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N_Cook <diverse@tcp.co.uk>: Dec 02 05:42PM On 02/12/2015 16:29, N_Cook wrote: > If I was on the analysis team I would have demanded much deeper > exploration of the fault. I assume I'm not unique, so was it done , but > the result supressed in this otherwise thorough report?   This is a macro-pic of a PbF solder ring crack I took a few years ago, when generally in repair jobs , it started becoming obvious there was a problem with PbF and vibration or thermal-cycling, in operation, after just a few years. Traditional Pb/Sn solder could also get ring cracks but after more like 20 years http://diverse.4mg.com/talk_crack.jpg Inappropriate hole dimension wrt to the diameter of a component pin is far more likely to end up with a ring crack than with traditional solder, with or without plated through pcb production.

Cydrome Leader <presence@MUNGEpanix.com>: Dec 02 06:57PM > On Tuesday, December 1, 2015 at 5:41:31 PM UTC-5, Cydrome Leader wrote:   >> carbon-stretcher?   > We made carbon-faced seals in one part of the shop - carbon is rather an unforgiving medium in any form. Something that got too small... well, you get the picture.   I had to fuss with graphite shaft seals a couple times. Yuck.   >> but the fasteners were bogus? For say liquid sodium pumps for the nuclear >> industry does each critical fastener get some sort of proof test?   > We purchased our fasteners from SPS (Standard Pressed Steel at the time). Their factory was less than 8 miles up the road in Glenside, PA. Several of the workers in our shop would go to their shop and work on the line with their people for our orders, just as I went to the heat-treat shop a few miles from SPS to supervise the heat-treatment of some of the critical parts, sometimes days at a time. Both SPS and Dreaver (now Evans) are still in operation today, and still have such intimate relationships with their customers. We took great care with the parts we made, and every part that went into them. Some parts took very nearly two (2) years in production.   Interesting. Sounds like you were hands-on with all parts and processes, even external ones.   Larger companies on the other hand probably just have to trust the initials on a test report as long as the 900 barcodes on the packaging scan correctly. I wonder how long it would take Beoing or Digikey to pull bad parts from the warehouse.

N_Cook <diverse@tcp.co.uk>: Dec 03 04:15PM On 02/12/2015 17:42, N_Cook wrote: > Inappropriate hole dimension wrt to the diameter of a component pin is > far more likely to end up with a ring crack than with traditional > solder, with or without plated through pcb production.   In that pic, X, is the component pin. I assume the crazing/furrows at different angles, is related to that sudden freezing optical effect of PbF going solid. Traditional solder just goes from molten to solid with no visual change to the surface appearance. The outer section of the solder blob does not have that crazing, so perhaps differential stressing is built in , before any operational stresses.

jcs7415030@gmail.com: Dec 03 03:01AM -0800

jcs7415030@gmail.com: Dec 03 03:01AM -0800

jcs7415030@gmail.com: Dec 03 04:09AM -0800 Au secour mon pioneer pd 73 ne s allume plus

Chuck <chuck@mydeja.net>: Dec 03 08:26AM -0600 >Le jeudi 3 décembre 2015 12:01:10 UTC+1, jcs74...@gmail.com a écrit :   >Au secour mon pioneer pd 73 ne s allume plus Does the CD play and the display doesn't illuminate or is the player totally dead? (morte)   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 03 06:34AM -0600 OK, so it appears there is very little to discuss on this group in areas like repairing audio components, amps, receivers, power supplies, etc these days.   I "tune in" here almost daily and rarely find anything of interest to me.   Maybe we could share some "war stories" of cool repairs we have done in the past.   Re-live some past glories?   The first time you traced down a bad reset line for a microprocessor?   That integrated amp that blew a channel about once a year until you caught that bias diode occasionally opening up?   Sansui 5000A's? (yuck)   Crappy Euro caps in Tandberg tape decks?   Those times you sweated whether you could even get this thing put back together?   Any more recent successs stories to brag about?   C'mon, don't we all enjoy patting ourselves on the back, really?     Mark Z.

N_Cook <diverse@tcp.co.uk>: Dec 03 12:41PM On 03/12/2015 12:34, Mark Zacharias wrote:   > Any more recent successs stories to brag about?   > C'mon, don't we all enjoy patting ourselves on the back, really?   > Mark Z.   My favourite was the car audio cassette player, ie no record function. It recorded vinyl record clicks on to any prerecorded tape played in there. Answer at end of spoiler defeat, run of +                 +                           +                     +                           +                                                       The pinch wheel had a tiny piece of magnet fragment embedded in it

N_Cook <diverse@tcp.co.uk>: Dec 03 12:36PM The owner cannot detect a difference. Other than different gain settings are obvious, how to set up and test? . I've not put a scope on there yet, but what set of parameters to confirm there is a difference, compressor or no compressor, max or min of contour settings, what sort of level and frequency of presumably over-driven input? Test not requiring guitar input and ear-drums, as then it becomes subjective/musical ears required. The valve actively tests fine.   Incidently seriously crap "engineering" on the speaker outlet board, especially as it is PbF. 2 legged 1/4 inch socket, no extra dummy legs for mechanical strength, so 2 simple active PbF joints supposed to hold the pcb and 2 thick unconstrained supply wires , laughable.

jose.canedo007@gmail.com: Dec 03 01:49AM -0800 did you get the manual? am also looking for it

jcs7415030@gmail.com: Dec 03 03:16AM -0800 Je cherche un fusible mais je le trouve pas j ai bien le manuel mais il n en parle pas car il a marcher il y a 2jours et mintenant +rien si vous savez merci pour votr   e aide a tous a charge de revanche pour des depannages sur cette gamme pioneer

jcs7415030@gmail.com: Dec 03 04:06AM -0800 Slt help mon pd73 pioneer ne s allume plus merci de reponses a +jcs7415030

"Arfa Daily" <arfa.daily@ntlworld.com>: Dec 03 02:27AM "Fred McKenzie" <fmmck@aol.com> wrote in message news:fmmck-C855FA.10123121112015@5ad64b5e.bb.sky.com... > people would become engrossed, trying to figure out the flashing > sequence!   > Fred   Ha ! I built one too when I was an apprentice. I seem to think that the circuit was in Practically Witless magazine. There used to be an aerosol deodorant at the time which had a blue spherical cap. I had about 12 neons in my version, and had them poked through holes in one of those caps - a bit like a WW2 sea mine. Quite by chance, the neon that flashed slowest was the one that poked vertically out of the top. It was all run from a single 90 volt battery, housed in a box made from modeling plasticard under the deodorant cap. The one thing that I do recall is that it also had a switch to alter the way the neons flashed. I seem to remember that one leg of all the neons were joined together and connected to battery -ve. Likewise, one leg of all the caps were joined together. When they were left 'floating', the flash of the individual neons was very 'soft' and hypnotic and random. The switch took the commoned capacitor legs to battery -ve. With the switch closed, the flashes were much 'sharper' making the whole display much more 'frenetic' looking. The current drain was so small that a battery lasted a year or more (which was just as well, as they were expensive. I think I still have a bunch of neons somewhere. I might try knocking one up again ... :-)   Arfa

jcs7415030@gmail.com: Dec 03 03:27AM -0800 Merči a tous je vais verifier la capacite qui se trouve avant le transfo d alimentation a +merci pour l information

whit3rd <whit3rd@gmail.com>: Dec 02 09:55AM -0800 On Tuesday, December 1, 2015 at 5:23:03 PM UTC-8, Michael Black wrote: > tubes (the leads were generally laid out in parallel with each other, and > the leads were relatively low gauge wire) seen in hearing aids and some > portable radios.   I've heard those called 'pencil tubes'; the ones in hybrid walkie-talkies (for the transmitter) didn't get replaced with semiconductors until mid-to-late seventies. Nuvistors were ceramic-metal base, metal envelope tubes, very rugged, and much less microphonic than other vacuum tubes. There was a long period when they were the best fast-slewing amplifiers around, and for HV handling (like electrostatic deflection in CRTs) very hard to replace with silicon.

Michael Black <et472@ncf.ca>: Dec 02 01:30PM -0500

"Ian Field" <gangprobing.alien@ntlworld.com>: Dec 02 07:15PM "Michael Black" <et472@ncf.ca> wrote in message news:alpine.LNX.2.02.1512021325170.11559@darkstar.example.org... > those tubes did offer the chance to make equipment smaller, and certainly > in the early days of transistors, the tubes had better high frequency > response.   They didn't have any transistors in WW2 - but they needed a crude doppler radar for proximity shells that could be fired out of an anti-aircraft gun.   AFAIK: they used what were basically ruggedised hearing aid valves potted in wax to stop them bouncing about.

M Philbrook <jamie_ka1lpa@charter.net>: Dec 02 06:39PM -0500 In article <alpine.LNX.2.02.1512012024220.10269@darkstar.example.org>, et472@ncf.ca says... > portable radios. I think those came early enough that they had a longer > span, but they too were whiped out by transistors.   > Michael   Yup, I have a drawer full of unused/new :)   Jamie

jurb6006@gmail.com: Dec 02 02:10PM -0800 Thank you for that post. Now we know who to boycott.   This is a Usenet newsgroup, NOT YOUR WEBSITE. Do like all the other assholes and hire a fucking SEO guy.

Leonardo Capossio <capossio.leonardo@gmail.com>: Dec 02 10:20AM -0800 On Tuesday, December 1, 2015 at 2:05:16 AM UTC-3, Phil Allison wrote:   > > You have to play for a while at low volumes (10min tops), or play for a minute at the highest volume. In idle, with a plug connected (otherwise the amp mutes), it does not shut down.   > ** When in "mute" mode, the power stage is completely shut down and cannot get hot. But does the heatsink get hot when active but not played, even if this take an hour ?   After half an hour, it is mildly hot, don't think it gets worse over a longer period of time.       > BTW:   > You are lucky the Frontman 212 merely shuts down, the ones I worked on all blew up as there was no over temp sensing device fitted.   > .... Phil   I'll try to de-burr this holes and do the thermal coupling correctly.

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