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jeanyves <jeanyves@nowhere.com>: Dec 09 09:19PM +0100 On 2015-11-21 01:24:25 +0000, Cursitor Doom said:   > these devices.   > thanks,   > CD   today the DEREE DE-5000 is the best bang for buck considering LCR meters precision those $20 multi testers are not precision instruments, but can be sufficiant for troubleshooting, not more. for me they are not lcr meters.   you can find deree de5000 on ebay ( in japan) for some $100 shipped dont forget the tweezers probes it is useless without.   example link here : http://kripton2035.free.fr/LCR%20meters/lcr-deree5000-cl.html   --   Jean-Yves.

Chuck <chuck@mydeja.net>: Dec 09 08:22AM -0600 On Tue, 8 Dec 2015 10:40:56 -0800 (PST), John-Del <ohger1s@aol.com> wrote:     >It auto selects between NTSC and PAL when played back, and it has a selectable output of either.   >When playing an NTSC tape, it auto selects NTSC and plays a perfect picture in color on an NTSC LCD TV via AV input. When a pre-recorded PAL tape is played, it auto selects PAL properly, but the picture on the monitor is black and white horiz bars, as if the horizontal hold was off just beyond lock. However when PAL is selected as an output (despite the monitor being NTSC), the picture appears in black and white and with a "texture" to it (like playing a component input on the composite jack).   >Not sure if something is wrong with the machine or some sort of incompatibility between equipment. He said it worked years ago the last time it was tried, but that was on an RCA analog TV.     We have 2 of these vcrs at work and they will play back PAL tapes with an NTSC output if NTSC is set as the output in the menu and if the tape is recorded in SP mode. EP recorded PAL tapes won't play back properly.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

N_Cook <diverse@tcp.co.uk>: Dec 08 03:55PM The DSP works giving a spacey output but only when the Intensity control is at 3/4 to full, so too much, and straight through input sound component very low level. Straight through, effects off, is good normal signal level out. The pots and switches check out ok, the mode switch is resistive and does the mode change ok.

N_Cook <diverse@tcp.co.uk>: Dec 08 04:32PM Looking closer, corrossion product from beer or whatever near the input and SMD FET and a 4558, gives something non-dsp, to probe tomorrow, no mention of beer-swilling of course.

N_Cook <diverse@tcp.co.uk>: Dec 09 03:16PM 2 topcode XG marked FETs? on the board, both with 21.7V on and other pins reasonable looking DC on them, one with corrossion around. No mention of phantom power in the user manual, I wonder what that is doing near the input. 9.3V fed onto battery supply line. 2x JRC 14558,IC4 and IC2 that one in corrossion , the other some way away, 0,8.2V supplies and 6x 5.5V on the other pins. The corroded one power rails and only 2, pins 3 and 5 commoned at 5.5V 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

"Gareth Magennis" <sound.service@btconnect.com>: Dec 08 06:55PM This is doing my head in.   Marhall JCM 600. http://www.classictubeamps.com/schematics/Marshall/jcm600_60w.pdf     Turning the distortion channel's gain/volume/master volume combination up too high will break into oscillation (a few kHz) above a certain gain. This doesn't happen unless the pre-amp is unmuted by inserting a (shorted) jack in the input socket.   As these 3 series gain controls approach the point of oscillation, you can hear the inpending frequency that will feed back rise as the gain is increased. (i.e. before feedback, the boosted frequency is gain dependent)   (Under certain test conditions it will oscillate massively ultrasonically. It's probably best not to do that very often)     Another amp repairer has been inside this amp and has attempted to fix the problem by the looks of it. He's put small caps across some electrolytics, and there was a resistor piggy backed over the top of R4, feeding VR5. Not sure why. I haven't found any other "mods", but that's not to say there aren't any.     Anyway, I've tried to isolate various things to discount them, but am going round in circles and need some ideas my head doesn't have right now.   There's some frequency dependent positive feedback going on somewhere, but since it's a complete loop broken by muting the input, it's kind of hard to isolate anything really. (Actually the input jack mutes both the input and the signal at CN6)     Any quick hints or tips from anyone? (It's not the Prescence feedback circuit, or the valves)       Cheers,     Gareth.

N_Cook <diverse@tcp.co.uk>: Dec 08 08:15PM On 08/12/2015 18:55, Gareth Magennis wrote:   > Cheers,   > Gareth.   Missing or inadequate ground line?

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 05 02:34PM -0600 Here's one.   Onkyo cassette deck, circa 1986. Perhaps a TA-630 or some such.   Played just fine in PLAY mode.   In REC mode only, the auto-stop would trigger at random times.   Partially open bridge rectifier. One of those little black round ones. In PLAY mode the voltages held up, but in REC mode the additional load of the bias oscillator dropped the voltage enough to cause the problem.   Ripple waveform was definitive. Showed 1/2 wave pattern where it should have been full-wave.     Mark Z.

Chuck <ch@dejanews.net>: Dec 05 03:37PM -0600 >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.     In a similar vein to your remote story, we sold an $1800 Tandberg cassette deck that came to the shop over and over again for not responding to the transport keys. In the shop it always worked perfectly. I decided to go to the customer's house after work to see what the problem was. At his house, the keys didn't work. I spotted a light dimmer on the wall. Turning it off and the deck worked perfectly.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Chuck <ch@dejanews.net>: Dec 05 03:22PM -0600 On Sat, 5 Dec 2015 14:34:50 -0600, "Mark Zacharias"   >Ripple waveform was definitive. Showed 1/2 wave pattern where it should have >been full-wave.   >Mark Z.     These bridge rectifiers also caused weird problems in Onkyo receivers of the 1980s.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Chuck <chuck@mydeja.net>: Dec 11 10:46AM -0600 On Fri, 11 Dec 2015 06:02:13 -0600, "Mark Zacharias" >than the prospect of this guy working for B&O.   >(no he didn't get hired)   >Good times. Mark,   In the early 70s there was a company that sold strips of rubber of various sizes with a razor blade, jig and a tube of super glue that was supposed to be used to make belts for consumer electronics equipment. I had never seen super glue before so I tried it. Once.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

M Philbrook <jamie_ka1lpa@charter.net>: Dec 05 07:14PM -0500 In article <1449310629.173856@news.evonet.be>, c4urs11@domain.hidden says... > 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.   And what was the charge for that?   $1 for resetting the switch and $9,999.00 for knowing which one?   Jamie

M Philbrook <jamie_ka1lpa@charter.net>: Dec 05 07:24PM -0500 In article <nsl66bdu96kpnnu4lapfpgmoor5h862hs6@4ax.com>, ch@dejanews.net says...   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   While I was in a neighborhood visiting a nice looking girl, a friend of hers ask if I could go over to their place and see why their portable color TV near the door had messed up colors they could not remove.   I really didn't want to go and told them it would be a minimum of $20 bucks just to walk in, they accepted.   So I walked in and didn't even bother to turn the TV on. I reached up on top of the TV set and removed the 9x6 Triaxal Speaker with a large magnet on it, sitting there for what ever reason, I have no idea why.   I held my hand out for the money! They asked aren't you going to even turn it on? I said, you can do that, they did and could not believe what they saw. I took the money and said, have a good day now..   Jamie

Bruce Esquibel <bje@ripco.com>: Dec 06 12:03PM > I had an SX-828, bought it sometime in the early 70s. > Been so many years, I don't recall the problem, but > I tossed it about two years ago, just too much stuff.   Heh, anyone else reading this, before you toss it, check ebay for the completed listings on both working and non-working audio stuff from the 70's and 80's, it's nuts.   Even if that 828 was broke, it seems to fetch $100-$150 and the working ones $200 on up.   Some of the top of the line ones from back then (pio sx-1980, sansui 5500 i think) in the thousands. This isn't the old tube stuff like Fisher and Marantz, just the popular solid state crap from the 70's and 80's.   The power amps and speakers don't follow but anything with receivers and turntables from that period, you probably can make back what you paid for it new, and then some.   -bruce bje@ripco.com

Chuck <ch@dejanews.net>: Dec 06 01:18PM -0600 On Sat, 5 Dec 2015 18:52:34 -0800 (PST), Phil Allison >> perfectly.   > ** Need more explanation for that one.   >.... Phil The light dimmer was putting an enormous amount of hash on the mains; somehow it was getting into the microprocessor circuitry. I had seen this before on much cheaper items so I had a hunch that this was the problem.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Dec 11 08:38PM > Maybe we could share some "war stories" of cool repairs we have done in the > past.   I was called in unofficially to have a look at an X-ray machine in a university crystallography lab, there was an intermittent fault which shut it down after a few seconds of operation. The running time was getting shorter and shorter and the manufacturers had given up on finding the fault.   On the way there, I mentally ran through what I could remember about X-ray machines (apart from the obvious dangers) and realised that most of what I knew had come from reading my father's hand-written course notes in the 1950s; they dated from when he was trained as an army radiographerat the outbreak of WWII. I knew what an X-ray tube looked like as a symbol, but what did one look like in reality?   On being introduced to the faulty machine, I glanced around the room and saw a number of copper-and-glass objects on a shelf - and concluded that they must be spare tubes. Luckily, the manufacturers had furnished a full set of circuit diagrams and the lab had managed not to loose them, so I knew what I was dealing with, even if I didn't initially know how most of it worked. The circuits were all discrete components with intermixed transistor, diode and relay logic.   By the end of the first day, I had gained a fair idea of how the power supplies and safety circuits worked and had been instructed in the necessary safety drill by the technician, so I was able to fire the machine up and watch what happened. The fault showed up, but it all happened so quickly that I wan't able to spot what was going on.   Luckily, on the morning of the second day, I happened to spot the tube current meter flicker downwards and the voltmeter kick upwards just as the fault occurred. Careful monitoring of the primary of the mains transformer showed unstable mains voltage, which the control loop had been over-compensating and then tripping out on over-voltage.   The cause was a burnt contact in the main contactor, so I stripped it down and sandpapered the contacts, much to the amusement of the staff.   Fault cured - machine saved from the scrapheap.     -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

Mike Tomlinson <mike@jasper.org.uk>: Dec 07 04:50AM En el artículo <vtm66b5hsssqq9u6s1fde1vo8t87vve09b@4ax.com>, Jeff   ><http://members.cruzio.com/~jeffl/nooze/support.txt>   Good fun. Thanks for posting that.   Number 10 reminded me of this:   https://en.wikipedia.org/wiki/Lp0_on_fire   My first-ever call out to a Unix system was to this very message.   -- (\_/) (='.'=) Bunny says: Windows 10? Nein danke! (")_(")

Chuck <chuck@mydeja.net>: Dec 07 07:56AM -0600 On Sun, 6 Dec 2015 17:23:59 -0800 (PST), Phil Allison   >Well shielded, low impedance gear is not affected but anything high impedance and not well shielded picks it up. Electric guitars and some keyboards are particularly susceptible.   >Seems your Tandberg was too and that is piss poor design.   >.... Phil Phil, Did you ever see the Tandberg cd player (1987) that cost over $1000.00 U.S. that had a plastic Philips chassis that never functioned correctly even when new? I was upset when I bought a Philips with the same chassis for $125.00 and had to return it. Imagine the flack we got when selling this turd.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Cydrome Leader <presence@MUNGEpanix.com>: Dec 07 05:21PM > 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.   Was that the type with the CD cartridge, like a trunked automotive unit? Those things were all such garbage.

Jon Elson <jmelson@wustl.edu>: Dec 07 05:40PM -0600 Mike Tomlinson wrote:     > Good fun. Thanks for posting that.   > Number 10 reminded me of this:   > https://en.wikipedia.org/wiki/Lp0_on_fire   Ah, we had a couple of those. We had a fairly large 360 system at Washington University. 1401 and 7094, then 360/50 and then 360/65.   One of the routines that made one think of CIA dead drops in the middle of the night was the routine for printing paychecks. (I guess vendor checks were similar, too.) They had the box of continuous form checks locked in a bank vault in the basement of the administration building. The box was taped shut with signatures across the seal. When they opened the box, two people had to be present and they had to sign a log sheet with the serial number of the top check. They carried the box to the computer center, loaded it into the printer and the program printed a sample form with VOID-- VOID--VOID all across it, but other info in the right place so they could align the forms. When all was OK, they told the program to print the checks. Then, they had to fill out and sign the log sheet reporting which forms serial # were used in the aligning process and the first and last forms serial # of the printed check run. Then the whole process was reversed to get the box sealed and locked into the vault. During the whole process, nobody was ever supposed to leave the side of the printer.   Well, imagine the confusion when in the middle of the print run the printer started sparking and set the continuous forms checks on fire! I heard about this 2nd hand, but apparently the accounting guys were running around like decapitated chickens! They didn't even know how to properly log what had happened.   I'm pretty sure we had another paper on fire event, but it was just standard print output that time.   Jon

Chuck <ch@dejanews.net>: Dec 08 11:45AM -0600 On Mon, 7 Dec 2015 17:21:35 +0000 (UTC), Cydrome Leader >> which also didn't allow any downward movement of the mechanism.   >Was that the type with the CD cartridge, like a trunked automotive unit? >Those things were all such garbage. No. It was a 5 disc carousel. Kenwood didn't have a design in the pipeline so they outsourced it.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Cydrome Leader <presence@MUNGEpanix.com>: Dec 08 07:52PM >>Those things were all such garbage. > No. It was a 5 disc carousel. Kenwood didn't have a design in the > pipeline so they outsourced it.   Sort of sad somebody messed up a carousel. The cartridge based changers were infuriating.   Anything that requires extensive soldering and screwing around with that medical type tape to open up, like portable tape/CD players and now cameras suck too.

Clifford Heath <no.spam@please.net>: Dec 12 12:41AM +1100 On 12/12/15 03:05, Percival P. Cassidy wrote: >> Any Li-ion 3.7V 18650 will do as a replacement (peak charge voltage >> 4.2V) - but get a matched set of 5. > If I have to get a matched set -- of ten (five *pairs*)   When did your need for five cells become ten?   > -- rather than of two, I might as well get two 4AH ones for $99.   To my knowledge, no-one has worked out how to make a 4AH 18650 cell yet.   The best cells are below 3.5AH, and five of those are already more than $49 without building a case. Ryobi is Chinese now, so they're almost certainly lying.   If you value high capacity, buy your own branded cells.

N_Cook <diverse@tcp.co.uk>: Dec 03 08:01PM On 03/12/2015 19:41, Gareth Magennis wrote:   > Gareth.   So how does he or I determine whether things are as they should be or that there is some failure with one or both of those channels? I'll put a scope on there and suck it and see with different sine f and levels of input and different other control settings.

"Gareth Magennis" <sound.service@btconnect.com>: Dec 03 07:41PM "N_Cook" wrote in message news:n3pcr2$lef$1@dont-email.me...   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.           There is a lot of audible difference between the valve stage and the transistor stage in the HA3500, it's deliberately designed in. If the owner can't hear this there is no point in him owning such an amp.     As for "testing" this stage, I would have to ask why do you need to test this stage? What do you hope to achieve by doing so? How are your results actually going to make any sense?       Sometimes there is just no substitute for a pair of ears and a brain.         Gareth.

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