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Eremita Analogico <LEDITApaolo.carrer@DALNASOlibero.it>: Jun 12 08:04PM +0200 Hi, I'm Paolo from Italy. I'm attempting to repair a Radio Test Set (Advantest R3361) that exhibit a strange fault that (I suppose) is originated in some digital stage.   https://s26.postimg.cc/9hwc9nr15/IMG_2473_1.jpg   Do you know where I can try to search fo fix it? I have the electric diagrams. Many thanks.

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 12 11:26AM -0700 On Tuesday, June 12, 2018 at 2:05:02 PM UTC-4, Eremita Analogico wrote:     > https://s26.postimg.cc/9hwc9nr15/IMG_2473_1.jpg   Paolo:   A picture is truly worth 1,000 words, but a more complete description of the fault would be useful. And, in addition to the schematic, do you have the user-manual? This may be a set-up issue.   http://www.g7lwt.com/documents/advantest/ocr_r3361a.pdf   I know that 455 pages may be a struggle - but when in doubt, read the directions.   Good luck!   Peter Wieck Melrose Park, PA

Eremita Analogico <LEDITApaolo.carrer@DALNASOlibero.it>: Jun 12 08:38PM +0200 > Good luck!   > Peter Wieck > Melrose Park, PA   Hi Peter, thanks for your reply and for the manual! The fault consist in a "toothed" displayed waveform. The Tracking Generator seem to be also malfunctioning, but I think that this is another issue; the toothed waveform is displayed with an external input signal. I have both service and user manual, and I (and my colleague) have tryed a lot of set-up with no results. Waiting for new ideas, I will try to read more deeply the manual, thanks.

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 12 11:48AM -0700 On Tuesday, June 12, 2018 at 2:38:34 PM UTC-4, Eremita Analogico wrote:   > I have both service and user manual, and I (and my colleague) have tryed > a lot of set-up with no results. > Waiting for new ideas, I will try to read more deeply the manual, thanks.   Do you have another scope to verify that the input signal is truly smooth, and that the toothed display is the actually the fault of the device?   Just making sure that the diagnostics have covered all the necessary ground.   Peter Wieck Melrose Park, PA

dplatt@coop.radagast.org (Dave Platt): Jun 12 12:13PM -0700 >I have both service and user manual, and I (and my colleague) have tryed >a lot of set-up with no results. >Waiting for new ideas, I will try to read more deeply the manual, thanks.   I'd check for the obvious, first: scope out all of the power-supply busses and see if you see any kind of noise on them.   The toothed waveform, and the fairly consistent height of the tooths, makes me suspect that the output of the log amplifier is being corrupted... possibly by a regular variation in voltage. If the Advantest uses a switched-mode power supply to create its analog supplies, there might be a fault in the supply which is causing it to dither between two different voltages... and this could throw the log amp all out of whack.   The same fault might be affecting the tracking generator.

jurb6006@gmail.com: Jun 12 04:08PM -0700 >"...output of the log amplifier is being corrupted... possibly by a regular variation in voltage. If the Advantest uses a switched-mode power supply to create its analog supplies, there might be a fault in the supply which is causing it to dither between two different voltages."   If you are right it may be as simple as a filters. I have a tendency to scope the supplies first unless indications are clear that that is not the problem   What we do not see with the still is whether those square type waves are stationary or they move, roll across the display. If they do move and they change direction or velocity with line voltage the answer is right there.   That's the simple answer, if that ain't it then that could be a problem.

Eremita Analogico <LEDITApaolo.carrer@DALNASOlibero.it>: Jun 13 05:41PM +0200 > If you are right it may be as simple as a filters. I have a tendency to scope the supplies first unless indications are clear that that is not the problem   > What we do not see with the still is whether those square type waves are stationary or they move, roll across the display. If they do move and they change direction or velocity with line voltage the answer is right there.   > That's the simple answer, if that ain't it then that could be a problem.   Hi, preliminary tests was done some times ago, and if I remember right, the various supply lines do not have ripples. When I got time, I will try again to verify supplies. The tooths are stationary over the waveform.

Jeff Liebermann <jeffl@cruzio.com>: Jun 12 04:17PM -0700 On Mon, 11 Jun 2018 22:42:37 -0700, The Real Bev   >Anybody remember DAC?   Yep. It was DAK Industries Incorporated. <https://en.wikipedia.org/wiki/DAK_Industries>   >had a local store with an open-box section -- full of breadmakers. They >eventually went belly-up, which was sad. The guy tried to start back up >a few years later, but it didn't work out.   I worked for a marine radio company that offered free warranty repair for life for the original owner. I watched 10 year old radios, that looked like they had been raised from the bottom of the Great Dismal Swamp being repaired. Others looked like they had 1/2 inch thick growth of fungus and mold on everything. One had obviously been installed in the path of a diesel generator exhaust. Fortunately, we didn't get too many of such radios back under warranty, so it was somewhat tolerable (except for the tech doing the repair). I asked the company president why he offered such a liberal warranty policy. He answered that he had no choice. It was the only selling point that the company could offer that the big guys in the business (Motorola) could not.   >> <https://www.amazon.com/gp/help/customer/display.html?nodeId=201532130>   >Somewhere I read you can return Amazon stuff at Whole Foods stores, >which might or might not be more convenient than shipping it back.   I don't know and am too lazy to Google for the info.   If Amazon can deliver product via a drone, they should be willing to accept returns shipped in the same manner. I don't know if it will work, but it certainly would be interesting to try.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

The Real Bev <bashley101@gmail.com>: Jun 12 08:03PM -0700 On 06/12/2018 04:17 PM, Jeff Liebermann wrote:   >>Anybody remember DAC?   > Yep. It was DAK Industries Incorporated. > <https://en.wikipedia.org/wiki/DAK_Industries>   Thanks. I knew it was Drew A. Kaplan, but thought it was spelled with a C but nobody spells it that way so I must be wrong :-(   > He answered that he had no choice. It was the only selling point that > the company could offer that the big guys in the business (Motorola) > could not.   I worked in QA for a company which shall remain nameless. I discovered that certain components on their wave-soldered boards failed regularly. The solution was a liberal return policy -- if somebody returned it overnight, it was fixed and shipped out overnight the same day, but it was ALWAYS fixed and returned the same day. It was also given fresh batteries, which provided an endless supply of lightly-used AAs for the employees that knew about it.   >>> <https://www.amazon.com/gp/help/customer/display.html?nodeId=201532130>   >>Somewhere I read you can return Amazon stuff at Whole Foods stores, >>which might or might not be more convenient than shipping it back.   Free delivery for Prime users from Whole Foods. They should damn well send it by limo and include a massage for the prices they charge!     > If Amazon can deliver product via a drone, they should be willing to > accept returns shipped in the same manner. I don't know if it will > work, but it certainly would be interesting to try.   Possibly :-)     -- Cheers, Bev "Mr Panetta also revealed that the US Navy Seals made the final decision to kill bin Laden rather than the president." --S. Swinford, The Telegraph [Aside from that minor error, those Seals did a fantastic job!] --Bev

micky <NONONOmisc07@bigfoot.com>: Jun 13 03:37AM -0400 In sci.electronics.repair, on Tue, 12 Jun 2018 20:03:54 -0700, The Real >>>which might or might not be more convenient than shipping it back.   >Free delivery for Prime users from Whole Foods. They should damn well >send it by limo and include a massage for the prices they charge!   I wonder if you'll be able to return lightly used food.

Terry Schwartz <tschw10117@aol.com>: Jun 13 05:32AM -0700 > Thanks. I knew it was Drew A. Kaplan, but thought it was spelled with a > C but nobody spells it that way so I must be wrong :-(   I come from a long line of "K" Kaplans.   In high school, I worked in a little deli. One customer would come in, she knew my family.... and she would proudly announce "picking up an order for Caplan, that's CAPLAN with a C"... every time. I think she did it just to be a prick. I always responded, "oh, I thought Kaplan was always spelled with a K".

stratus46@yahoo.com: Jun 12 10:14PM -0700 On Thursday, June 7, 2018 at 12:47:53 AM UTC-7, Martin Brown wrote:   > -- > Regards, > Martin Brown   At work we have a commercial food dehydrator for baking video tapes that absorb water and become sticky.   We also have a dishwasher to clean circuit boards. The dehydrator is excellent for drying electronics. I usually run 6-10 hours at 125° F.   G²

makolber@yahoo.com: Jun 12 10:23AM -0700 for FM DX, you want a radio that you can switch to MONO mode.   mark

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 12 11:19AM -0700 > for FM DX, you want a radio that you can switch to MONO mode.   > mark   The GE "SuperRadio" comes immediately to mind.   Peter Wieck Melrose Park, PA

jurb6006@gmail.com: Jun 12 04:36PM -0700 >"Continuously variable for FM doesn't make sense."   Maybe not, but...   In the old days there were stations that sounded better when off tuned, and I mean with the dual tuning meters. This can only be because the multipath was at the edge of the IF bandwidth and mistuning took it out of the passband. If so, the simple loss of the harmonics obviously caused less distortion than the multipath would.   Luxman believed it and had a ine for a few years that actually detected multipath and would actually mistune a station for lowest distortion based on the multipath measurement obviously.   Thus, even better would be variable control of both the upper and lower sidebands. this would allow you to tune in the center of the detector range and do what the Luxman did, or what mistuning did a long time ago. Adjusting it manually would be a different story of course, few people could figure it out.   However being in the center of the detector range is simply not important now that they usually have a much wider range than the IF bandwidth. The Luxman engineers probably figured that is would be pretty rare for the multipath to happen at both sidebands and figured that the easiest way to do it would be mistuning.   I have seen such a tuner in action. It would tune of course, then it went into the test type mode and you could see the tuning indicator change and there was another small indicator on there that I think indicated the detected multipath.   That was actually one of the best mix/match systems I heard. The Luxman was a receiver and fed a pair of ADS which had blown tweeters. The other amp fed a Bose Acoustimass system with the satellites right on top of the ADS'. And I could not get it to clip. I shook the floor pretty good, and the house was built on a slab. Longwood, Florida, every house is on a slab unless you are filthy rich and want to waste money. Certain times of the year if you stand in one spot out in the yard you start sinking, that is if the fire ants don't get to you and make you go in. Of course there was also the alligator in the swamp next door...   Anyway, I think DXing anything is not what it once was. All the digital garbage on the signal, you limit the IF bandwidth that is sure to cause some distortion. And even some of the best old tuners need a modification just to handle the signal without spurting a bunch of noise into it. As far as DXing TV which I used to do, that is over period. It seems like they don't want us watching things that are not meant for the area. Like Canadian news I used to watch on CFPL, channel 10. Now we have the internet and they are having a hard time stopping that. Ever look at RT ? Sure they are biased, but they are not off the wall. Even PressTV, biased ? Sure, but CNN ain't ? Bullshit.   And BTW, you can get most FM in the country on iheartradio.com I think, though it may have limitations applied. Like youtube "this video is not available in your country". But there are programs that can spoof your location. Consider them the new DX antennae.

makolber@yahoo.com: Jun 12 10:26AM -0700 > This TV, located in the basement, is connected to a power strip with a > switch that "disconnects" everything that is plugged into the power strip.   is it damp in the basement? leave the TV on for 10 hours to let it dry out. mark

John-Del <ohger1s@gmail.com>: Jun 12 01:06PM -0700 > is it damp in the basement?   > leave the TV on for 10 hours to let it dry out. > mark   Guys, unless I'm reading the OP's post incorrectly, he fixed the TV with new contacts. I think he was just passing along the info and story.

jurb6006@gmail.com: Jun 12 04:00PM -0700 >"Guys, unless I'm reading the OP's post incorrectly, he fixed the TV with new contacts. I think he was just passing along the info and story. "   You're right. But the info applies to new TVs should a similar case come up.   That is unless it uses those capacitive buttons. Whoever decided to use those for this application needs to be boiled in bacon grease. On a pitch black background, and the labels only light up if you touch them, bullshit. I want a button protruding and I want tactile feedback. If they can't do that I will keep my 30+ year old TVs and when they no longer get a signal I will break out the VCRs. Actually they are out because there has been practically nothing worth watching produced in the past 25 years. Even the news. Instead of telling us what mischief city council is up to they want to tell us about this new gizmo we can buy. That is not news. Garbage.   Whenever possible I will hep to keep this old stuff running. Any exceptions, yes but they are really complete junk from back when. They were out there.   So it stands. Nobody can delete it anyway. But you are still right.

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