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Chuck <ch@dejanews.net>: Dec 04 12:21PM -0600 On Thu, 3 Dec 2015 06:34:55 -0600, "Mark Zacharias"   >Any more recent successs stories to brag about?   >C'mon, don't we all enjoy patting ourselves on the back, really?   >Mark Z. The receiver tech was flummoxed by one of those large 1970s Pioneer receivers. It had a problem none of us had seen before and we were a high volume audio chain. There was slight audio distortion on both channels, only on FM. We all worked commission only so I was the only one to volunteer to help him out. To cut to the chase, the receiver had an over designed mute circuit that was 3 or 4 stages deep, At the deepest stage there was one of the Sanyo electrolytics that became a common failure item many years later which was slightly leaky.   I've got another one. In the early 80s there were these 19" Hitachi tvs that ghosted. It looked exactly like a bad delay line. By that time I ran the TV service department for the same company. We had just switched over to the big box store concept and I was inundated with broken tvs. Out of desperation, I switched out the CRT and the ghosting disappeared. We sold 1000s of these sets and I saw the problem 3 more times.   And another. Kenwood sold these Funai made cd changers that never worked properly. All of them would come back with skipping or not playing discs problems. Kenwood came out with 3 or 4 mods, none which worked. Sometimes they would work for months before they came back. Somehow I found out if the mechanism retaining springs were stretched so the mechanism didn't sag at all, the problem disappeared. Called up Kenwood and they put out a mod kit that included strong springs which also didn't allow any downward movement of the mechanism.   Last one. There were these very expensive ADS cd players which would play any disc except a ,very popular at the time, Jimi Hendrix Ryko disc. Couldn't find any electronic or mechanical problems. I slightly moved the CD turntable slightly down on the spindle and this disc and all other discs would play.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

John-Del <ohger1s@aol.com>: Dec 04 10:53AM -0800 On Thursday, December 3, 2015 at 7:34:56 AM UTC-5, 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.   The one pops to mind took couple of years off my life. It was an old Hitachi built RCA projection TV (circa 1981) that had blown fuses in the power supply, but nothing showed a short resistance wise. I replaced the fuses and it powered up, only the geometry didn't look right. When I went to connect the cable back on to it to see exactly what the picture was like a blinding flash and arc appeared at the RF connector and it blew the fuses again. Working pretty much on my stomach in a cramped house, I traced a hot side/cold side short all the way back to the end of the line, which was a leaky deflection yoke (vert winding to horiz winding). It seems the horiz winding was on the hot side of the chassis and the vert winding was on the cold side. How it didn't blow the vert IC or horiz deflection output is a mystery.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 04 01:59PM -0500 "Chuck" <ch@dejanews.net> wrote in message news:vrj36blm2d6ad0ctibhqk01tuqmhfka57d@4ax.com... > had an over designed mute circuit that was 3 or 4 stages deep, At the > deepest stage there was one of the Sanyo electrolytics that became a > common failure item many years later which was slightly leaky.   Many electronic devices will have a common problem. It may take a while to find it,but once found, the first thing to look for.   I worked for a large company and we had a new building built and equipment installed. All was fine for a while, the some heaters for the process got where they would not come on if cut off. I was the first one to get a call about this. Took about 2 or 3 hours to troubleshoot this as it was the first time anyone had worked on it. Found a bad plug in time delay relay was bad. After that a simple one point voltage check would usually tell the relay was bad. Next time it only took seconds to change out the relay and was usually done any time they would not come on. 99.9% of the time that was the problem. As that place operated 24 hours a day, the peopel in production was told about it and told the electrician that showed up to change it out if they did not know what the problem might be. Saved lots of late night phone calls.

amdx <nojunk@knology.net>: Dec 04 02:28PM -0600 On 12/3/2015 6:34 AM, 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.   In the late 80s early 90's I worked on VCR's. The Fisher FVH 906, had a tuner that went defective, no schematic, a replacement part only. That's ok under warranty, but after that, the part cost was to high to get a repair ok. So one day, I decided to see if I could find out what the cause of the failure was. I started spraying parts with freeze mist and found when I hit a 1uf 35V cap the picture came back. I made a lot of repairs, replacing that same cap on a whole bunch of tuners. I'd do the same thing every time, dribble 2 or 3 drops of freeze mist on the cap and the picture came in.   I had a customer bring in a remote for repair, it checked out fine. He took it home and called saying it didn't work. I talked to him a bit and found he had just install new CFL lights. I suggested he shield that light and try it. It worked, I had just read about that in a trade magazine two days previous. Mikek   I got in early on the VCR curve, they were expensive, commanding high service rates, then when prices dropped we had a high volume of repairs, rode it down until the price was close to $200, then I moved to Florida. A year later the tech that took my place said he came in a couple days a week to repair the few that came in. I repaired a little over 11,000 vcr's in ten years, it was a good time.

Phil Allison <pallison49@gmail.com>: Dec 04 05:22PM -0800 > Ripped the offending extension out, the buzzing ceased immediately, > and the BBC and Public Image Limited got their recording and the > Sound Company didn't lose the gig or it's reputation.   ** I know of a similar example involving a 30kW, 3 phase lighting system for live entertainment here in Sydney. Was back when lighting consoles communicated with triac dimmer racks via 0-10V analogue signals. The system seemed to have a mind of its own, lights came up and varied about with all faders set to zero. Bringing one fader up affected many others.   After hours of fruitless searching, the culprit was identified as the AC plug on the lighting console itself which had neutral & earth reversed.   Seems a roadie had fitted a new plug after accidentally damaging the original and told nobody.     .... Phil

"Dave M" <dgminala@mediacombb.net>: Dec 04 09:06PM -0600 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.   One of my first chances to stick my chest out and strut was shortly after I checked aboard my first duty ship during my stint in the Navy in mid-1964. Barely 20 years old, I was assigned to overhaul & repair of UHF shipboard radio transmitters.   The ship had a small calibration lab, which was staffed by a PO1, a PO2s and a couple PO3s (POs are Petty Officers... enlisted men) who had all been to the elite Air Force PMEL calibration school in Colorado. One day, after all the cal lab techs had a shot at it and several of the other bench techs had also been called in to try fixing it,, I was called in to take a shot at repairing a new HP 524D 10MC digital counter from another ship. It just wouldn't show any indication of trying to count... all the displays just sat at zero no matter what the input signal looked like.   I sat down and took a look at the schematic, hooked a scope probe to the output of the gate tube, a 6AL5. No pulses. Hooked the probe to the gate input to the gate tube. Good gate pulses. Hooked the probe to the signal input of the gate tube. Good squared pulses that followed the frequency of the input signal. I asked for a 6AL5 tube, plugged it in, and Voila! everything came to life.   Made me feel kinda good that it only took me about 10 minutes to fix what had stumped 9 or 10 good techs for several days. From that day until now, I have had an affinity for test instruments, especially those used for time & frequency measurement.   Dave M

Phil Allison <pallison49@gmail.com>: Dec 04 08:08PM -0800 Mark Zacharias wrote:   > Maybe we could share some "war stories" of cool repairs we have done in the > past.   > Re-live some past glories?   ** Ok, here is a wacky one:   I once had a customer who rented out DJ systems: turntable & mixer consoles, stereo amps and speakers. DJs back then owned a collection of LPs and generally rented audio gear on a daily basis.   So I got this TT console with the complaint while it started off OK, it was losing volume & changing tone after a while becoming duller and duller until full treble was needed to correct it.   The story sounded dubious, but I checked out the mixer thoroughly using hot air and an all day soak test - result negative, it worked fine all the time.   Handed it back to the hire business guy and a week later it was returned with the SAME complaint plus some hostility that I had clearly not fixed it. Naturally it passed all tests again.   I had a chat with the hire guy and he agreed to use the console himself at a gig and of course it worked fine all night. Next time it went out on hire, he got the same complaint from the same DJ - who was by now ropable that nothing had been done about the problem.   So my hire guy paid a visit to the venue where the gear was being used, his first. When he walked in, he was nearly deafened by the volume and the sound was absurdly shrill. On approaching the DJ and noticing that volume and treble controls were all maxed out - he was told:   " See what I mean ??   Sounds piss weak and there's no treble."       .... Phil

jurb6006@gmail.com: Dec 04 09:20PM -0800 Chances are he'll never hear his grandkids cry.

c4urs11 <c4urs11@domain.hidden>: Dec 05 10:17AM On Thu, 03 Dec 2015 06:34:55 -0600, Mark Zacharias wrote:   > Maybe we could share some "war stories" of cool repairs we have done > in the past.   Somewhere in the eighties we installed a custom-built control system in a 24/7 assembly line for SIL ceramic hybrid circuits. Subcontractor of subcontractor job.   One night I was called in for an unexpected stop. Inside the plant I was 'greeted' by the crowd of tech support people and blaming managers gathered around our equipment. On my way to the control system I came across one of the typical mushroom emergency stops along the production line. By habit I twisted the knob and felt the release spring. I worked my way to the control panel and engaged the start. Within seconds the crowd silenced and fled the scene: the line was up.   We were never again called in.

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 05 06:26AM -0600 "c4urs11" <c4urs11@domain.hidden> wrote in message news:1449310629.173856@news.evonet.be... > I worked my way to the control panel and engaged the start. > Within seconds the crowd silenced and fled the scene: the line was up.   > We were never again called in.   About 1981 I was still in tech school and not even really a technician yet.   (I was SO green).   Third semester, servicing phase. There was an old GE tube chassis color set with intermittent color sync. It was a "re-do" which the prior class had failed to fix correctly.   I got to the burst gate amp and saw there was a much smaller signal at the grid than called for.   Also, there was a neon lamp in the grid circuit which was supposed to drop 75 or so volts and the drop was much higher than expected, plus the lamp glowed somewhat faintly at it's base instead of lighting fully.   I couldn't get the instructor to order a miserable 75 cent neon lamp. He kept me running around checking this cap or this resistor, etc.   Finally I went around him to another instructor, explained my logic and got the lamp ordered.   Fixed the tv. My instructor never really forgave me for that.     Mark Z.

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 05 06:52AM -0600 Things that are second nature to us now were "learning experiences" back then, yes?   At my first job as a tech, about the second piece I ever worked on was a Pioneer SX-828.   Yup - the infamous "blue Sanyo cap" scenario.   Except I had never heard of that and had no tech support or even a more experienced tech along side me.   I was totally on my own, as I usually was during the first 15 or 20 years of my career.   Symptom: one channel gone, just a low hiss. Preamp issue.   Tracing signal - got it, don't got it, and so on.   In the tone amp, DC voltage low at collector of one transistor.   1.5uF Sanyo coupling cap to base was leaky, driving that stage into saturation.   Felt really good about that one.     Mark Z.

mogulah@hotmail.com: Dec 05 08:01AM -0800 On Friday, December 4, 2015 at 1:53:47 PM UTC-5, Ralph Mowery wrote: > > common failure item many years later which was slightly leaky.   > Many electronic devices will have a common problem. It may take a while to > find it,but once found, the first thing to look for.   Most of them have microchips (that you can't open up and repair). And they have software and wireless or hard wired connections to larger facilities elsewhere where techs can come in and review the software.   Many problems seem to be caused from malware or spyware (maybe some even from the government or other places) that intentionally interferes with the intended software provided by the company on the package's label.   > I worked for a large company and we had a new building built and > equipment installed.   Right now, I'm not even working. I'm just sitting around looking at space cartoons and video games.

N_Cook <diverse@tcp.co.uk>: Dec 05 09:32AM > Cheers,   > Gareth.   So what does the tube EQ do that the 10 channel +/-15dB graphic cannot do?

"Gareth Magennis" <sound.service@btconnect.com>: Dec 05 01:05PM "N_Cook" wrote in message news:n3uar8$rko$1@dont-email.me...     > Cheers,   > Gareth.   So what does the tube EQ do that the 10 channel +/-15dB graphic cannot do?       Sells the amp?     Gareth.

mogulah@hotmail.com: Dec 04 12:40PM -0800 On Friday, December 4, 2015 at 12:37:26 PM UTC-5, Unquestionably Confused wrote in rec.crafts.metalworking: > you just go to your inbox, select display all (you can do this on hotmail > and Gmail, I believe) and then scroll down, highlight those mails you > want and...?   First (of course) turn the power off to everything. Secondly, hook up two fully-charged late-model wireless phones (brand unimportant) to the two thumb-drive jacks on your desk top, then, turn the power on to the desk top! Thirdly, check your yahoo email going back as far as you can. It should come up. On Friday, December 4, 2015 at 12:37:26 PM UTC-5, Unquestionably Confused wrote:

rodndtube@gmail.com: Dec 04 12:29PM -0800 What you might be hearing rattling around are little chips of coffee bean. With the top off you can move the base back and forth and probably see them roll around. Then empty into the trash. Do that a couple of times and the problem should clear up.   On Monday, March 24, 2014 at 10:34:35 AM UTC-4, KenO wrote:

"Gareth Magennis" <sound.service@btconnect.com>: Dec 04 07:19PM "N_Cook" wrote in message news:n3s8se$ss2$1@dont-email.me...     > Cheers,   > Gareth.   Local buskers to me , tend to get 12V, 10Ah ones , second hand, from a local motorcycle insurance write-off scrapper/parts seller. Busker use is much lighter use than starter motors, and his basic check over before sale , is adequate.           I was under the impression that conventional lead/acid car/motorbike batteries cannot tolerate deep discharges for very long.     Gareth.

"pez" <pez@research.net>: Dec 04 06:52PM +0100 The Radio Technology Plus TE, EE and CS Journal - - FunkTechnikPlus # Journal Collection at Internet Archive Digital Library :   https://archive.org/details/@funktechnikplusjournal

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