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N_Cook <diverse@tcp.co.uk>: Mar 04 02:21PM Passed a gig and recording session and no bounce back. Its quite easy to recondition the original pot+switches , with new stud ended stem. Much stronger and of course matching action to the others, unlike the flimsey new pots and of course proper pot/sw positions. The new pots , nothing stopping any of the tags turning on their rivets, and they had, at least they've dropped the mains rating of the originals as these rotating terminals would be utterly unsafe for mains use.

Tim R <timothy42b@aol.com>: Mar 04 05:37AM -0800 On Thursday, March 3, 2016 at 10:44:03 AM UTC-5, Jeff Liebermann wrote: > benefit is that Nitrile causes fewer allergic reactions. What you > want for solvent resistance is Viton or something with a silver foil > lining, such as Norfoil (used for Hazmat service) at $10/pair:   I have refreshed my memory on the time the rubber solvent ate the gloves.   (I found an old post where we discussed it.)   There were two of us dumping small containers into a drum. We thought it was all pretty much the same stuff, tiny bottles of solvents. The other guy was wearing latex gloves and I had on what we called triwall neoprene. Halfway through he let out a yell and ran for the emergency shower. His gloves had melted off and his hands were stinging. No real harm was done but it gave us a scare. When we checked that bottle it was the rubber rejuvenator. At any rate it didn't seem to bother my gloves but it destroyed his.

"pfjw@aol.com" <pfjw@aol.com>: Mar 03 09:37AM -0800 > Is it possible that you are putting them in backwards?   No, that was the _first_ thing I checked. Also the second, third and last. But, as stranger things have happened, and I am by no means perfect, I will check again!   Dan:   I will check the diode. That was replaced pre-me, so a valid concern.   Thank you both.   Peter Wieck Melrose Park, PA

dansabrservices@yahoo.com: Mar 03 11:03AM -0800 > Thank you both.   > Peter Wieck > Melrose Park, PA   Verify that the diode is installed correctly too. If reversed, it would affect the caps too.   Dan

"tom" <tmiller11147@verizon.net>: Mar 03 02:28PM -0500 <pfjw@aol.com> wrote in message news:eab85b47-2f5c-441d-a9d1-f1e0d5f8da02@googlegroups.com...   > Thank you both.   > Peter Wieck > Melrose Park, PA   And measure the 1.5K 2W. Is the transformer CT actually at ground? What is the voltage across the caps? Across the 220 ohm R? What do you see (with a scope) across the caps?

Phil Allison <pallison49@gmail.com>: Mar 04 04:31AM -0800 > Here is the Schematic: http://komkris4000.webs.com/lk150%20schematic.gif   > It is eating the 150uF @ 75V filter caps - I replaced the OEMs first with 75V, 105F caps, they lasted about 20 hours. Then 100V, they lasted about 30 hours. The manifestation is increased HUMMmm, and the caps start to swell.     ** That schem looks wrong.   No way 75V electros should be fed from a 100V AC winding.   75uF @ 150V is more like it.   Is the secondary tapping really 100V rms ?   The hand written " -31 " is wrong too, should be more like -45V.     .... Phil

legg <legg@nospam.magma.ca>: Mar 04 08:09AM -0500 On Fri, 4 Mar 2016 04:31:49 -0800 (PST), Phil Allison   > Is the secondary tapping really 100V rms ?   > The hand written " -31 " is wrong too, should be more like -45V.   > .... Phil   It's possible that the original rectifier wasn't a silicon diode, and that an inaccurate replacement has been used.   Should be easy enough to measure the voltage on the caps to determine stress levels,   RL

"pfjw@aol.com" <pfjw@aol.com>: Mar 04 05:13AM -0800 On Friday, March 4, 2016 at 7:31:55 AM UTC-5, Phil Allison wrote:   > Is the secondary tapping really 100V rms ?   > The hand written " -31 " is wrong too, should be more like -45V.   > .... Phil   Phil:   I think you are right. In any case, the diode *was* in backwards - it is in a silly little brass shield grounded to the chassis - looks like a bit of brass tubing with a soldered on lead that covers the diode (1N4007 now, replacing a wrong-way 1N4004). I will check voltages with the existing slightly swollen caps for now, then replace them with appropriate voltage and capacity units - but no less than 180V at this point. As for testing purposes, I will be right there and with an eye on the current meter, I have no worries about a few minutes with bad caps.   Peter Wieck Melrose Park, PA

legg <legg@nospam.magma.ca>: Mar 04 08:29AM -0500 On Thu, 3 Mar 2016 08:01:41 -0800 (PST), "pfjw@aol.com" <pfjw@aol.com> wrote:     >Thanks in advance!   >Peter Wieck >Melrose Park, PA   Later rev schematics that employ silicon rectifiers in the -65V bias have a 6K8 2W bleeder across the first filter cap.   RL

Chuck <chuck@mydeja.net>: Mar 03 04:41PM -0600 On Thu, 3 Mar 2016 15:17:37 -0000 (UTC), Cursitor Doom >over time and shorts parts of the PCB out. The bloke who was explaining >it was convinced the manufacturers did it on purpose. I'm not convinced >myself, but who knows for sure?   It was rumored that the glue was made by Sony and that they sold it to other manufacturers but didn't use it themselves until many years later. T   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Chris Jones <lugnut808@spam.yahoo.com>: Mar 04 11:21AM +1100 On 04/03/2016 02:17, Cursitor Doom wrote: > over time and shorts parts of the PCB out. The bloke who was explaining > it was convinced the manufacturers did it on purpose. I'm not convinced > myself, but who knows for sure?   I think it might be used much more recently too. I have a DVB-T set top box that used to work fine but started locking up and generally crashing. The PCB had some brown glue that got dabbed in various places including around a RAM chip and onto some 0402 components. THe glue had started to discolour and it looked like it was corriding the components. I picked off the glue and cleaned it a bit with solvent and I think I replaced one decoupling capacitor and now it works fine, no crashing. https://www.flickr.com/photos/37778900@N06/25484493195/

amdx <nojunk@knology.net>: Mar 03 06:31PM -0600 On 3/3/2016 4:41 PM, Chuck wrote:   > It was rumored that the glue was made by Sony and that they sold it to > other manufacturers but didn't use it themselves until many years > later. T   I don't know who made amn sold it, but Sony products also had the glue (resistor) problem.   Mikek

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 04 05:31AM -0600 > The surrounds on my AR-2ax's from about 1967 are still good. They are made > of rubberized cloth (probably silicone rubber). The acoustic suspension > concept requires having a good seal, and foam would not work.   The Advents were acoustic suspension. When the surround was good the piston motion of the woofer was damped , apparently enough to do the job.   mz

Jon Elson <jmelson@wustl.edu>: Mar 03 04:17PM -0600 Trevor Wilson wrote:   So, any luck on that printer?   Jon

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 04 11:07AM +1100 On 4/03/2016 9:17 AM, Jon Elson wrote: > Trevor Wilson wrote:   > So, any luck on that printer?   > Jon   **Thanks for asking. I've decided to head in a completely different direction. I've been able to source one of these:   http://au.pcmag.com/hp-laserjet-enterprise-500-color-mfp-m575dn/1374/review/hp-laserjet-enterprise-500-color-mfp-m575dn#   for AUS$400.00. It has full toner cartridges (except one, which is at 20%). It has a full service history (it came from a large corporation, that has swapped out all it's printers from one section) and was factory serviced a couple of months ago. I'll be checking print quality and collecting it next week.   -- 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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