- Consumer electronics "war stories" - 8 Updates
- Best type of battery for busking amp - 1 Update
| jurb6006@gmail.com: Dec 06 09:46AM -0800 You can get them cheaper if you get lucky. Some of those three day auctions on eBay n shit. But there is quite a number of people who appreciate that old stuff. Like me, I see no reason my amplifier needs wifi. I knew we were going downhill when I saw an amp with an RJ-45. And to me, this new stuff mostly sounds like shit. And I don't like the idea of 12 balsa wood speakers the quality of a 1966 table radio and one woofer. Stereo was invented because we got two ears. I might even tolerate quad, but 7.1 ? Nope. I have a hard enough time understanding the words in stereo and on TV I usually switch it to mono. Anyway, the prices of some of this stuff are outrageous. A Marantz like my old one, $700. Look up the price of a Marantz 2385. A Pioneer SX-1980. (not sure but I think that was the most powerful receiver ever built) Recently a turntable went for $55,000. What's more I talked to my buddy and mentioned that and he told me they go higher, up into six figures. And now, down in Sydney, Australia, Elton John was spotted in a record store buying albums. The guy can afford anything he wants but he wants a record player. (and logically, records of course) There is quite the renewed interest in vinyl these days. Even youngins. Guys on AK for example talking about how they just got their teenager a turntable and an old vintage system. Sometimes for their college dorm if that is where they live, other times wherever. In fact right now we are setting up something of a lab for this stuff. Distortion tester, standards to calibrate everything for power output measurements, and more to come. The idea here is to be sure the stuff is working right because when it is 40 years old it can have insidious problems that only distort a little and won't be noticed right away. And when you get them running really right, that old 1970s shit blows most of the new shit away. Don't get me wrong, there is a high end still but if you think about 1979 dollars and a receiver is $400, how much would that be today ? Well, it IS. The same relative level of quality easily costs four times the money. What you get for $400 is like what you got for $79 back then, although THAT quality is a bit better. Just not that much. Not enough for me. I don't use it, but I got a Pioneer SX-850. No lid, no bottom, glass in front broke, tuning shaft bent. Power suppl.y board was broke in three places, needed work on that, one channel of the power amp and the preamp as well ! It works. It is a rag. It is filthy but everything works. Not for sale. |
| jurb6006@gmail.com: Dec 06 09:57AM -0800 Well I guess it is my turn. NAP bigscreen no sound - vertical control IC. Everything runs off the data and clock lines. This IC does the "S" correction and things like that pertaining to linearity. It is of course bus addressed. The one line, data or clock, doesn't matter, was clamping the signal down to like 2 volts. Leaky. That meant the data from the EPROM was not read when the unit got initialized so it did not know which sound system it had and never upped that. Sony 32" loses green and blue - adjust vertical height. This was an interesting comedy of failure mode. Apparently when they came out with AKB a had to be done to the CRT aperture grill frame. It reflected too much. The CRT had just been replaced. The way I figure it they used a dud from a non-AKB set. When the pulses feeding the cathodes to detect the current got to the frame they reflected like all hell and told the circuit there was too much green, and then blue as the circuit drifted a bit and brought the lines over the metal. I found this out with the scope. I mean, there is no green but it is getting alot of green feedback. WTF ! And THEN, to adjust the vertical you use a service menu. Guess what color the numbers and letters are in that menu. They were not red but if you left the set on for a while all you had was red. I got some good ones about cars too. |
| 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 |
| jurb6006@gmail.com: Dec 06 02:53PM -0800 I almost want to say it was a fault, but it may have been the design. Really, when you talk old stuff, some things just did not exist back then. Things that cause more interference. When working on older equipment, much older, I had to learn not to expect too much. In that case with the Tandberg I would have gotten some line filtering. they make those all put together units you can put right at the AC input, light enough so you can cut the cord even and just glue them about anywhere, just make sure they are as close to the AC inlet as possible. To figure it all out we woukld need the print for that Tandberg. I remember working on one R2R deck that had no microprocessor. It was all gates and comparators and all that. I think it was a 9200 ??? So that one probably would have been alright, no keyboard scanning or any of that, just a bunch of switches and flipflops and gates. and then the solenoid and relay drivers, oh and the current drivers for the eddy current motors. Simple, I liked it. I fixed it. It got sold. It got damaged in shipping. We got fucked. I wish I would have kept it but really, I have no tapes. |
| Phil Allison <pallison49@gmail.com>: Dec 06 05:23PM -0800 Chuck wrote: > 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. ** Wall dimmers put large voltage spikes on the wiring going to the lamp/s concerned - two spikes per cycle at up to the peak AC voltage. This radiates as buzzing noise across the audio and also AM radio bands. 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 |
| 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! (")_(") |
| whit3rd <whit3rd@gmail.com>: Dec 06 11:39PM -0800 On Sunday, December 6, 2015 at 5:24:04 PM UTC-8, Phil Allison wrote: > > somehow it was getting into the microprocessor circuitry. > ** Wall dimmers put large voltage spikes on the wiring... > Well shielded, low impedance gear is not affected but anything high impedance and not well shielded picks it up. There's another possibility: knob/tube wiring puts those spikes on distant HOT and NEUTRAL wires (not a close-spaced pair). So, there can be significant magnetic induction, and that can mess up low impedance circuitry. It used to be seen a lot in CRT television pictures as deflection jitter. You have to worry about low impedance, too (balanced pair helps). |
| 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 |
| Tim R <timothy42b@aol.com>: Dec 06 01:24PM -0800 On Friday, December 4, 2015 at 2:20:03 PM UTC-5, Gareth Magennis wrote: > I was under the impression that conventional lead/acid car/motorbike > batteries cannot tolerate deep discharges for very long. > Gareth. I've seen buskers with the super quiet small Honda generator. |
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