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"Gareth Magennis" <sound.service@btconnect.com>: Dec 13 10:31PM "Mark Zacharias" wrote in message news:LFW7y.253701$4M.32862@fx17.iad...   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.               A very distant fellow band member of mine once confided in me that he one day discovered his next door neighbour had the same television that he had. He had many hours of glee from sneaking up to their window and randomly firing his remote control at their TV.     He also ended up being prosecuted for stealing commission cheques meant to be mailed to our management company.   Not a particularly nice bloke.       Gareth.

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 13 09:07AM -0600 Sometimes a small victory makes you feel just as good as a big one.   Picked up a somewhat non-functional Micronta 22-220A multimeter. A little rough but the FET meter circuit worked - voltage readings weren't too far off and the zero control did it's job so I knew all that stuff was OK.   But the resistance function acted as though there was a 4 ohm or so resistor across the leads all the time, and the battery was draining at about 100 mA in Ohms function even with no leads attached.   Of course the 9.1 ohm Rx1 resistor was bad, but replacing it did NOT change the symptom.   After finding a schematic (not many out there...) I did find a component labelled "SA1" shorted at 4 ohms or so. The item resembled an MOV and I can only assume SA stood for spark or surge arrestor.   Removing it mostly fixed the ohms function, and I decided a couple of back-to-back 25 volt zeners would offer enough protection to satisfy my needs.   Still the ohms zeroing was erratic. Cleaning the function / range switch and ohms pot til I was blue in the face did not resolve the problem. It was kinda usable but it kept bugging me.   I tried putting a current meter in series with the test leads but couldn't really get a usable correlation between pushing, poking wiggling the function switch etc and the action of the meter which might zero fine, then show up to several ohms even seconds later with probes shorted.   It occurred to me that I could put a resistor (say 4.7 ohms on this range) across the probes and put a 'scope across that resistor to better see what the DC voltage there was doing.   Oh, yeah. the voltage as viewed on the 'scope varied wildly and looked "noisy" as the funtion switch was wiggled or tapped.   But I had cleaned that switch umpteen times.   Well, there was another switch - a leaf switch, going to the negative battery terminal hiding under the front face and also actuated by the function knob.   A quick cleaning of those contacts and the meter works like new.   A small victory to be sure, but made me feel as good as a big one.     Mark Z.

N_Cook <diverse@tcp.co.uk>: Dec 14 09:28AM On 13/12/2015 22:31, Gareth Magennis wrote:   > Gareth.   On practical joking, this was to wind-up my parents , when I was aged about 10. A syncronous mains driven/timed mantle clock . I was intrigued by this little flipper/kicker thing that operated when you turned on the power. If you disengaged it with a match, then half the time , when switching back on, the clock would go backwards.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 14 10:04AM -0500 "N_Cook" <diverse@tcp.co.uk> wrote in message news:n4m1un$jkq$1@dont-email.me... > little flipper/kicker thing that operated when you turned on the power. > If you disengaged it with a match, then half the time , when switching > back on, the clock would go backwards.   That reminds me of a clock we had when I was growing up. On the back was a small wheel and you had to spin it in the direction you wanted the clock to run when it was plugged in.

MJC <gravity@mjcoon.plus.com>: Dec 14 03:08PM In article <EuadnXCyGaPJR_PLnZ2dnUU7-c-dnZ2d@earthlink.com>, rmowery28146@earthlink.net says...   > That reminds me of a clock we had when I was growing up. On the back was a > small wheel and you had to spin it in the direction you wanted the clock to > run when it was plugged in.   If only one could "turn the clock" back and recapture one's long-gone youth that way...   Mike.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Dec 14 10:15AM -0500 On 12/14/2015 10:08 AM, MJC wrote:   > If only one could "turn the clock" back and recapture one's long-gone > youth that way...   > Mike.   I wouldn't be 21 again on a bet.   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

Cursitor Doom <curd@notformail.com>: Dec 14 02:05PM Anyone care to share their experience on the correct approach to troubleshooting? I'll kick off by suggesting:   1. Assume nothing.   Perhaps we can assemble a list of golden rules....

gyro_john <john.wetzel@shaw.ca>: Dec 14 04:47AM -0800 On Monday, October 12, 2015 at 7:44:43 AM UTC-6, Madness wrote:   > > Just a thought.   > > -bruce > > bje@ripco.com   Almost 40 years ago, when I used to fix these things for money, it was almost always a traction problem caused by the capstan being overly polished. I tried fine emery cloth, but what worked great was: - remove the capstan with its drive pulley. - put it on a record player turntable and get it spinning. - heat up the polished part of the capstan shaft with a propane torch until it would glow dark red for a few seconds. - the spinning is an attempt to prevent warpage. - let it cool and reassemble.   The surface will now be a dull matte finish and the traction problem is gone. Never had to do it more than once in the life of an 8-track player.   Hope this is of interest.

N_Cook <diverse@tcp.co.uk>: Dec 13 12:32PM On 13/12/2015 11:18, Adrian Tuddenham wrote: > believe Cecil Watts's wife published a biography of the firm, although I > have never seen a copy.   > If you want more help with this, please contact me (I live in the UK).   wow, what a lot of info that pdf would seem to be now on http://www.bl.uk/britishlibrary/~/media/subjects%20images/sound/analoguesoundrestoration.pdf not read it yet. I'll take a pic of the label and also the reverse with spindle hole and the drive dog hole. Label says "SPEED 50 R.P.M" At the moment I was only trying to think how to fudge a deck to play it. Hang the motor upside down and a 50/45 scaled from the 45 pulley,replacement pulley, if I can find one. I seem to remember not only inside to outside but counterclockwse rotation. Hopefully minimum stylus pressure No idea about antiskating and handedness of the arm at the moment. May end up replaying in reverse and then electronically reversing it. No intention of even applying distilled water to the surface for the moment.

N_Cook <diverse@tcp.co.uk>: Dec 13 01:37PM 3 pics of this disc http://www.diverse.4mg.com/marguerite1.jpg http://www.diverse.4mg.com/marguerite2.jpg http://www.diverse.4mg.com/marguerite3.jpg the third is the reverse, the label on the front is covering over the drive dog hole, viewed from the rear. The tearing around the spindle hole is the only obvious failing of the film, clumsy positioning over a spindle in antiquity? Film laid down like silicone slivers and resist etc in chippery production? spun at high speed with a dot of liquid on the disc? The colours are about right, plum-brown in flat light and coppery tone with slanting light reflecting off the aluminium. The apparent grooves on the rear is probably machining marks of the Al blank. Perhaps the 50rpm business was a "pirated" manufacturer trying to escape patent infringement, I suppose patent library is one route to look into. I'll check again , but the blank space between 2 tracks, with continuation groove, spirals in such a fashion that playing from sinside to out , the disc would be spinning normal clockwise , so hopefully normal handedness of the tonearm and normal antiskating weight.

"Gareth Magennis" <sound.service@btconnect.com>: Dec 13 01:55PM "N_Cook" wrote in message news:n4js67$cli$1@dont-email.me...   3 pics of this disc http://www.diverse.4mg.com/marguerite1.jpg http://www.diverse.4mg.com/marguerite2.jpg http://www.diverse.4mg.com/marguerite3.jpg the third is the reverse, the label on the front is covering over the drive dog hole, viewed from the rear. The tearing around the spindle hole is the only obvious failing of the film, clumsy positioning over a spindle in antiquity? Film laid down like silicone slivers and resist etc in chippery production? spun at high speed with a dot of liquid on the disc? The colours are about right, plum-brown in flat light and coppery tone with slanting light reflecting off the aluminium. The apparent grooves on the rear is probably machining marks of the Al blank. Perhaps the 50rpm business was a "pirated" manufacturer trying to escape patent infringement, I suppose patent library is one route to look into. I'll check again , but the blank space between 2 tracks, with continuation groove, spirals in such a fashion that playing from sinside to out , the disc would be spinning normal clockwise , so hopefully normal handedness of the tonearm and normal antiskating weight.         You might only get one shot at playing this disc, it may be destroyed by that process, as has been suggested.   This may not be your world, but I would take Adrians advice and try and take a digital recording via a normal turntable at 45rpm, if the handedness and anti skate should work the same. Speed/EQ adjustments and even reversing the audio can be done later, much more safely, in software.     Cheers,     Gareth.

adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Dec 13 02:43PM > http://www.diverse.4mg.com/marguerite1.jpg > http://www.diverse.4mg.com/marguerite2.jpg > http://www.diverse.4mg.com/marguerite3.jpg   Typical centre-start transcription disc of the period. Broadcasters sometimes used centre-start to make sure the louder climax of a performance was recorded at the highest surface speed to give best quality.   Common practice for continuous programmes lasting longer than one disc side was to use two recording machines (often with a single common amplifier). Sometimes thesae were set up so that one recorded outside-in and the other inside-out, this meant that the changeover on playback was less noticeable because the surface noise didn't suddenly change its quality. This system was not popular with the playback operators, who had to check each side carefully and often made mistakes.   The label suggest that there is no question that the intended playing speed was 50 RPM - but it is definitely non-standard.   To vary the speed without a lot of butchery, connect the turntable motor through a step-up auto-transformer to the 100v output of a large P.A. amplifier. Feed the amplifier from an audio signal generator and adjust the frequency to get the required speed change. Carefully monitor the motor current and adjust the amplifier gain so that it is maintained at a similar value to the normal 50c/s current, otherwise you will burn out the motor at low frequencies.   Alternatively, look out for a secondhand Lenco turntable with infinitely variable speed.     > The tearing around the spindle hole is the only obvious failing of the > film, clumsy positioning over a spindle in antiquity?   No, these discs weren't played many times, so it is more likely to be caused by shrinkage of the laquer film pulling away at the centre. It also appears to have delaminated at the rim for the same reason.   > Film laid down like silicone slivers and resist etc in chippery > production? spun at high speed with a dot of liquid on the disc?   ...or edge dipped into a bath of laquer whilst rotating slowly. Both techniques were used.   > The colours are about right, plum-brown in flat light and coppery tone > with slanting light reflecting off the aluminium. The apparent grooves > on the rear is probably machining marks of the Al blank.   They weren't usually machined, the blanks were stamped out of sheet aluminium. Without examining this one closely, I wouldn't like to guess at what caused that.     > Perhaps the 50rpm business was a "pirated" manufacturer trying to escape > patent infringement, I suppose patent library is one route to look into.   No chance, hardly anybody but the BBC and GPO could get hold of MSS blanks during the war; the GPO ran the factory. By 1944 aluminium was in very short supply, so private recordings, when they could be made at all, were being made on glass and even galvanised iron blanks (they were heavy!). The BBC monitoring services recorded onto wax cylinders.   > continuation groove, spirals in such a fashion that playing from sinside > to out , the disc would be spinning normal clockwise , so hopefully > normal handedness of the tonearm and normal antiskating weight.   A centre-start disc still rotates in the conventional direction, it is one of the few conventions in the recording world that never seemed to be flouted. The only time you would need a reversing turntable is if you needed to play it backwards to recover a lost turn because of a jumped groove.     -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

N_Cook <diverse@tcp.co.uk>: Dec 13 03:33PM On 13/12/2015 14:43, Adrian Tuddenham wrote: > be flouted. The only time you would need a reversing turntable is if > you needed to play it backwards to recover a lost turn because of a > jumped groove.   I think I'll go with the larger pulley, even if not giving exactly 50rpm it will be constant at a measurable speed. The other letter in front of AY 1 may be a J, so JAY 1, a ragtime pianist of 1940s called Jay Something ? The blemish at the rim on the front face is a splodge of powdery paint or tippex, easily removable if/when I dare to clean the disc. No damage on the active face film, a few spots missing on the rear. I'd played it sometime for about 5 seconds, the track stayed intact, played well enough to tell by my nonmusical ears it was a pleasant piece of ragtime piano or some such style of music. I suppose they were double sided discs but only one face recorded on this. But the exposed Al on the rear near the spindle hole does not show machining marks. Perhaps there was an attempt at recording on the rear, but at too low a pressure, it feels smooth to the touch, and the film patterning goes right to the centre. I wonder if the use of Persian blue, endorsing ink (stains well into paper fibres for legal document use) is relevant or that is just the ink pad they had there then. Another recovery program I must get back to sometime is 3 spools of used taperecorder wire that came with a rusted up Magnetophon , circa mid 1950s. one of these https://www.soa.hr/galerija/6/m/1-1_Minijaturni_magnetofon_sa_zicom_b.JPG Hardly anyone could afford one of those pocketsize (well greatcoat pocket) covert recorders, then. It would be unlikely they were erased (unless it was a dismissible conduct if not erased before disposal ) as required the use of batteries only, and no fast erase. 3 batteries to power the peanut valves and motor. I got the motor and mechanics free running again, but ran out of time , before cross-connecting the head to the head wiring of the R/P head of a modern cassette recorder, to hear what,if any, is recorded on the wire.

x@nospam.com: Dec 10 02:48PM -0800 Phil Hobbs wrote: > twirling spaghetti, but french fries? Seriously?   > Cheers   > Phil Hobbs   How unAmerican that you do not smother your fries in ketchup! lol       --- news://freenews.netfront.net/ - complaints: news@netfront.net ---

Cydrome Leader <presence@MUNGEpanix.com>: Dec 11 12:52AM > I guess bar-b-que, burgers, fried chicken and french fries are great, but not if you are wearing a buttoned-up shirt that day. So, if you have to eat lunch with a client and other contractors in a diverse environment, what would you recommend? > I remember I was watching Seinfeld and somebody ordered chicken or tuna fish salad. Yeah, that's something I could agree with... especially with lettuce, tomato, mayonnaise on well-done toast, with plenty of black pepper and a pickle slice and a cup of coffee. That would seem less "trashier" than slobbering over friend chicken, bar-b-que and coke, right?   If your are known for anything "good"?   Had one repair guy drive from Michican to Chicago for a single service call. He seemed keen on getting an Italian Beef (It's a Chicago-area sandwich nobody outside the area can get right for some reason). He just wanted to know what place to try.   It's something I take for granted, but they're a big deal for visitors.

Chuck <chuck@mydeja.net>: Dec 10 08:02AM -0600 On Wed, 9 Dec 2015 13:12:03 -0800 (PST), John-Del <ohger1s@aol.com> wrote:     >I talked to the owner and he again told me that this machine played his PAL tapes on an RCA 32" analog CRT TV. It was put away for a while and now he wants to play some tapes from home for his grand kids, and that's why he tried it recently.   >I tried it again today and it now plays the PAL prerecorded tape with a normal, clear, and stable picture when NTSC output is selected. Unfortunately, it's in black and white but at least it's now in horiz sync. I'm thinking there might be a horiz phase adjustment somewhere I can tweak. If the horiz is right on the edge of break, it might be causing the loss of color. I tried cooling the machine down to see if I could get the horiz to drift again, but it hasn't (suspecting aging electrolytics).   >Anyone have a link to a SM?   John,   This one should be close. http://www.manualslib.com/manual/469008/Aiwa-Hv-Mx100.html   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

N_Cook <diverse@tcp.co.uk>: Dec 10 02:43PM On 09/12/2015 15:16, N_Cook wrote: > and 4 pins with all sorts of DC and varying somewhat, in effects on or > off mode. > So off with that SMD and a 4558 will go in there and see what happens   Normal function returns for all that Star-Trekky stuff. 4.1V dc (half 8.2V) now on both 4558 pins ins and outs, all 12 such pins. I'll try and find out how beer got to where it pooled , as not an obvious landing place.

N_Cook <diverse@tcp.co.uk>: Dec 03 08:57PM This is an ebay purchase. Forgot to say I pulled the valve and that fully killed throughput of the tube channel. Reasonable looking DC on the valve base. No provision in the schematic for adjusting bias , other than component change in the self-biasing chain. Another engineering problem with this amp. Steel cab bolts into tapped alumimium and seized threads (whetever that steel/Al semi-welding process is, not corrossion, melding?) . Previous person had ended up sheering one of the bolts and stripping the heads of the remaining ones. Matter of removing the corner protectors off the cab , then remove the other bolts to the angle plates, then mole-grips on the sheered bolt stem. Vaseline on all such threads before returning, including the replacement 4 x 6mm replacement front retaining bolts.

N_Cook <diverse@tcp.co.uk>: Dec 04 12:51PM Monitoring send out. All controls mid, except graphic out, solid tate 0, tube mid and compressor off. Minimum sine input to show soft clipping is at about 400Hz, requiring 1.05V rms in. Then hard clipping coming in about 1.5V rms. I'll take that as normal "tube" function

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.

N_Cook <diverse@tcp.co.uk>: Dec 04 02:46PM > 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.

"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.

Cydrome Leader <presence@MUNGEpanix.com>: Dec 03 10:41PM >> neons for a digital display.   > See https://picasaweb.google.com/111741851908838288378/CEDRICProject? > authuser=0&feat=directlink   Nice case. How old is that thing? What's inside?

Cydrome Leader <presence@MUNGEpanix.com>: Dec 03 10:36PM > Living in the south I doubt much if any of that 'odd ball' power was used. > About the only "odd" voltage I see is some 208 volts phase to phase with 120 > to the neutral instead of the 240 p to p.   208 phase to phase means you're looking at two legs of three phase power, and not split phase 120-120 like in a typical home.

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