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John-Del <ohger1s@gmail.com>: Jun 29 11:50AM -0700 > > OLED TV quite considerably (his rough calculation out it as going from > > 100,000 hours down to 25,000 hours).   > You have to wonder where the already-shorted-out TVs are, for example.   From the article: "I wouldn't worry too much even if I was an average viewer, someone who watches nearly five hours of TV per day. Addicts and others who need a 24/7 TV, however, should probably stick with LED-backlit LCD.'   Bad advice. LED backlit TVs have a lifespan measured in hundreds of hours, not thousands in many cases. I've done close to a thousand LED jobs over the last few years. Modifying the current source afterwards is critical to prevent comebacks. These TVs run the LEDs beyond their safe rating in order to make them "pop" at Walmart. The original CCFL LCD TVs lasted many tens of thousands of hours.

"~misfit~" <shaun.at.pukekohe@gmail.com>: Jun 30 10:50PM +1200 Once upon a time on usenet John-Del wrote: > afterwards is critical to prevent comebacks. These TVs run the LEDs > beyond their safe rating in order to make them "pop" at Walmart. The > original CCFL LCD TVs lasted many tens of thousands of hours.   At least I'll know where to get advice if / when my Samsung LED-lit LCD has trouble before I want to replace it.   I'd love an OLED TV (my phone screen is awesome!) but it's not an option on my budget. -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

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Chuck <ch@dejanews.net>: Jun 28 12:46PM -0500 On Wed, 27 Jun 2018 15:43:58 -0700 (PDT), captainvideo462009@gmail.com wrote:   >parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   >Chuck >I put a remote near the antenna and it does respond to AM. I did see it respond to FM at one point too. But then it didn't seem to after awhile. The thing is I can't find VR2 that you mentioned. Which meter is the signal meter? Lenny Lenny, M705. I wonder if the the meter movement is sticky?

captainvideo462009@gmail.com: Jun 28 02:11PM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   Chuck I'm embarrassed to say that I think I know what happened. The RF section on this receiver is pretty hot and so for servicing it on my bench I didn't bother connecting the old outside VHF/FM antenna that is now used just for FM, throughout our house. I was getting what I thought was a decent signal in my basement with just a short piece of wire connected to the high side of the 300 ohm terminals. Apparently in spite of the fact that the FM stations I was tuning in sounded OK there must be a signal threshold that must be met before the signal meter will move. With the unit connected to the outside antenna the signal; meter is now working fine. I don't think that there was ever a problem with it. It was more aptly due to "operator head space"   So now I'm at the final stage of this repair. I have owned this receiver for over thirty years now. I originally bought it from the junk man at our town dump who was going to strip it, for 5.00 It has been a great receiver for all this time,however the 4 channel circuitry never seemed to work properly on it. I worked on it, John Del, also a contributor to this thread worked on it as well, but we never seemed to be able to resolve it. So for that time I have lived with it.   A few weeks ago I was browsing Craig's List and found a guy about 30 miles from my house who had one of these for sale. I went out, and looked at it and thought it might need a discriminator alignment, and I picked it up for parts. So today, first I swapped out the 2048 board. I now have output on all 4 channel positions except the first and last, which seems like it should be. I have 4 speakers connected to speaker A front and back terminals. It seems to sound "OK:" but I can hear a very slight "popping" way down in the mud in the rear speakers.   So I was going to swap out the 2047 board, however in spite of the fact that it would fit in the same slot as my original, the board from the donor receiver is totally different. For one thing there are 7 potentiometers on the donor board and only three on my original board. There are also two 8 pin chips on the original board but it seems to be all discrete components on the donor board. So for boards that fit into the same positions in the chassis are these boards forward and backward compatible? After all this I would hate to make a swap and because it was incompatible wind up destroying something. Lenny

Chuck <ch@dejanews.net>: Jun 29 11:06AM -0500 On Thu, 28 Jun 2018 14:11:48 -0700 (PDT), captainvideo462009@gmail.com wrote:   >backward compatible? After all this I would hate to make a swap and >because it was incompatible wind up destroying something. >Lenny Lenny, The board compatibility question I can't answer. Back in the day we never switched out whole boards on Sansuis. Always troubleshot to the component level. Sorry. Chuck

Miguel Teixeira <geotexmig@gmail.com>: Jun 29 07:07AM -0700 Hi, I´m a doing a historical research on a Spectra Physics Laser model nº136, produced in U.S. in 1960´s/70´s: https://imgur.com/a/zRSXMFE   I'm really interested in details related to production of this model and his catalogue. I just found this one: https://www.repairfaq.org/sam/brochures/SPOHLC1975/index.html but probably there are more specific documents.   I appreciate all information that you might share about this device Thank you, Miguel

bruce2bowser@gmail.com: Jun 28 08:37PM -0700 On 2018-06-27 22:33:46 +0000, Your Name said:     > The author's basic conclusion is yes, HDR does shorten the life of an > OLED TV quite considerably (his rough calculation out it as going from > 100,000 hours down to 25,000 hours).   You have to wonder where the already-shorted-out TVs are, for example.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Jun 28 08:45PM +0100 Hi,   this is the amp schematic:   http://tinypic.com/r/wlxjrm/9   The amplifier works normally, except on Power up and Power down, there is a huge low frequency DC offset going on which sounds and is very alarming. Here's a scope capture. http://tinypic.com/r/5pjslw/9   The bottom blue trace is the Mute signal at the base of Q30. The Yellow trace is the power amp output, at 20v per division, so pretty much full swing.   All these traces are without any load, but it does pretty much the same thing with a load.   The first mute signal positive is at switch on, the second is at switch off. Horizontal sweep is one second per division, so what you see is turn on, wait 4 seconds, then turn off. There is a sine wave running through the input, which you can see after both mutes unmute, (the fat lines below the zero point), showing the amp is indeed muting and passing the signal when it should.   If you disable the mute signal by shorting C151, thus connecting Q30's gate to ground and turning it on constantly, you get the following trace. http://tinypic.com/r/4szokx/9   There is a switch on spike, but no long drawn out DC stuff going on any more, which leads me to suspect the muting is causing this to happen. As you can see by the fat line, the signal is now passed immediately at switch on, as the mute is now disabled.     I can't find anything obviously wrong, and the amp works normally except for the huge anomalies at switch on and off. The negative feedback seems to be in circuit, the Power supplies are all normal and power up immediately.   I changed Q30 for good measure, no different.   This is mostly SMD stuff, so not that quick and easy to whip stuff off and on again for testing.     Amplifiers are not my most favourite circuit, and I don't know a lot about how DC offsets are managed in them, but it seems this one definitely has a problem managing the DC.         Cheers,     Gareth.

Phil Allison <pallison49@gmail.com>: Jun 28 05:29PM -0700 Gareth Magennis wrote:   > Amplifiers are not my most favourite circuit, and I don't know a lot about > how DC offsets are managed in them, but it seems this one definitely has a > problem managing the DC.   ** SRM450 is the model number of a Mackie powered loudspeaker, the schem is for the amplifier module that drives the 12inch woofer.   Thing to note is that such units undergo frightening amounts of vibration plus the occasional impact with the floor - which can put cracks in the PCB and or loosen components that are not extraordinarily well held down.   No amount of perusing and pondering over a schem will find any of that.   Nevertheless, the muting system is a common one in that the front end of the amplifier is starved of current so it can no longer drive the following class A stage and hence the output stage. Q30 does this by disabling Q29 & Q31 and hence both input diff pairs ( Qs 25 thru 28)   So, one needs to engage the mute circuit ( apply +10 or more to Q30's base) and see why that is NOT happening correctly. The amplifier circuitry is symmetrical so look for a voltage that is not reflected on the opposite side in mute mode.       .... Phil

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amdx <nojunk@knology.net>: Jun 28 09:22AM -0500 > Or, close enough.   > Peter Wieck > Melrose Park, PA   Sometimes it would be nice for an OP to say, Hey, thanks for the help, or you're F'ing nuts and don't have clue. Just something, so we know they didn't get hit by a car!

JBI <JBI@ez1.net>: Jun 28 11:33AM -0400 On 06/28/2018 10:22 AM, amdx wrote:   >  Sometimes it would be nice for an OP to say, Hey, thanks for the help, > or you're F'ing nuts and don't have clue. Just something, so we know > they didn't get hit by a car!   Quite right, Thank you ALL!

Chuck <ch@dejanews.net>: Jun 27 12:18PM -0500 On Wed, 27 Jun 2018 00:30:50 -0700 (PDT), captainvideo462009@gmail.com wrote:     >I really don't see how but could this be some crazy kind of coincidence, or perhaps something associated with the lighting system problem?   >The tuner section of the schematic, F-1479-2A shows two meters and one small 6V 100ma lamp. Please correct me if I'm wrong but M705 looks like it could be the signal level meter and M706 looks like it is connected to the discriminator output for station centering. Then there is that small 6 volt 100ma. lamp which is connected off pin 12 of the board. Could that be the stereo lamp? To troubleshoot the signal level problem would M705 simply get a DC output off that HA1120 chip and through the transistor proportional to signal strength? Thanks for any further help. It is very much appreciated. >Lenny Lenny,   Does the meter work on AM? If it does then either there is a bad connection from VR2 on the F1479 board to the meter or, more commonly, the potentiometer is faulty. If it doesn't work on AM, either the meter coil is open or the wire to ground or the plus wire from the circuit board is open or C 98 is shorted. Hope one of these hunches is correct. Chuck

captainvideo462009@gmail.com: Jun 27 03:43PM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   Chuck I put a remote near the antenna and it does respond to AM. I did see it respond to FM at one point too. But then it didn't seem to after awhile. The thing is I can't find VR2 that you mentioned. Which meter is the signal meter? Lenny

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captainvideo462009@gmail.com: Jun 27 12:30AM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   Chuck   First, thank you very much for the power supply jumper information. I hope that I will not have to use it but it is comforting to have it. The reason I say this is because in the interim I tried my Blue Stuff treatment. I sprayed the switch sections quite liberally and I really worked the switch through all of it's positions.   What I had previously written about the effect that Blue had on the intermittent phenoclic switches in the old tuners was not an overstatement. My display lamps are all on now and there is no smoke. I guess that I would say that I'm "cautiously optimistic" that I may actually have restored these tarnished contacts before they actually had a chance to burn.   I've turned the receiver on a few times now since the Blue Stuff treatment and and the display has come on strong without flickering each time. I guess we'll see.   Now I have to address the other problem with the non functioning signal meter. As I had said it always worked before and never caused a problem. But now it just lights up and does not indicate signal.   I really don't see how but could this be some crazy kind of coincidence, or perhaps something associated with the lighting system problem?   The tuner section of the schematic, F-1479-2A shows two meters and one small 6V 100ma lamp. Please correct me if I'm wrong but M705 looks like it could be the signal level meter and M706 looks like it is connected to the discriminator output for station centering. Then there is that small 6 volt 100ma. lamp which is connected off pin 12 of the board. Could that be the stereo lamp? To troubleshoot the signal level problem would M705 simply get a DC output off that HA1120 chip and through the transistor proportional to signal strength? Thanks for any further help. It is very much appreciated. Lenny

jurb6006@gmail.com: Jun 27 04:26AM -0700 >"non functioning signal meter"   Also goes through the switch, usually.

John-Del <ohger1s@gmail.com>: Jun 27 04:43AM -0700 > I really don't see how but could this be some crazy kind of coincidence, or perhaps something associated with the lighting system problem?   > The tuner section of the schematic, F-1479-2A shows two meters and one small 6V 100ma lamp. Please correct me if I'm wrong but M705 looks like it could be the signal level meter and M706 looks like it is connected to the discriminator output for station centering. Then there is that small 6 volt 100ma. lamp which is connected off pin 12 of the board. Could that be the stereo lamp? To troubleshoot the signal level problem would M705 simply get a DC output off that HA1120 chip and through the transistor proportional to signal strength? Thanks for any further help. It is very much appreciated. > Lenny   IIRC, the Blue Stuff product contained an actual abrasive along with the blue schmutz carrier. If the abrasive scoured the contacts into working, I think I'd follow it up with a non residue cleaner to get the blue carrier off. I remember the blue carrier thickening into a stiff almost glue like consistency over time.

Mike S <mscir@yahoo.com>: Jun 26 08:52PM -0700 On 6/26/2018 3:51 AM, Miguel Giménez wrote: >> activation code or page or something and that's it.   > Thank you for the information. Downloading is currently disabled, I'll > check from time to time. Externally they are very similar.   This site claims to offer the xr-m35 (no ez) for $4.99 http://www.manualscenter.com/manuals/aiwa/xrm35ezhehrk-service-manual.html

"~misfit~" <shaun.at.pukekohe@gmail.com>: Jun 27 12:06PM +1200 Once upon a time on usenet Charlie+ wrote: > Ok Done and dusted - instant-on press button works fine (just bypasses > the BMS negative on startup) - time will tell if it keeps on happily > trucking! Thanks for help everyone... C+   That's what I did when I converted a battery powered rotary tool from 3 x NiMH to an 18650 and the charge controller / battery protection module did the same as you're reporting. My system also worked fine. ;) -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

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JBI <JBI@ez1.net>: Jun 26 10:37AM -0400 I am getting a platinum coated anode that will have a surface area of 26 cm2 (100 mm long x 8 mm diameter). For my application, the maximum recommended current density is 200 mA/cm. Based on that, how much current should be flowing through the anode? I calculate square root of 26 (5.1) times 0.2 which is 1.02 A, is this correct? Thanks.

amdx <nojunk@knology.net>: Jun 26 10:16AM -0500 On 6/26/2018 9:37 AM, JBI wrote: > recommended current density is 200 mA/cm.  Based on that, how much > current should be flowing through the anode?  I calculate square root of > 26 (5.1) times 0.2 which is 1.02 A, is this correct?  Thanks.   I'm probably confused but, if it's 8mm in diameter, isn't it 25mm* in circumference? And, if it's 25mm, then 25mm x 100mm = 2500mm^2, convert to cm^2 and get 25cm^2. then multiply 200ma x 25cm = 5 amps. I'll let an adult correct me. I have never seen a platinum coated electrode.       * have not included areas on end.

JBI <JBI@ez1.net>: Jun 26 11:54AM -0400 On 06/26/2018 11:16 AM, amdx wrote: >   I'll let an adult correct me. I have never seen a platinum coated > electrode.   > * have not included areas on end.   You're at the same place I was originally when I did the calculation, which made me question whether or not I should take the square root of the area and then multiply that by current density. When I took the square, I got the 1.02A above, but much closer to your value when I didn't.   Platinum coated electrodes have many applications:   https://tinyurl.com/yaufchs3

"pfjw@aol.com" <peterwieck33@gmail.com>: Jun 26 09:06AM -0700 On Tuesday, June 26, 2018 at 11:16:09 AM UTC-4, amdx wrote: > I'll let an adult correct me. I have never seen a platinum coated > electrode.   > * have not included areas on end.   Lemme see- surface area of a cylinder = pi x D x H.   3.14159 x 8 = 25.133   25.133 x 100 = 2513.3   0.0200 x 2513.3 = 502.7   Divide by 100 (mm - cm) = 5.02 A.   add the end-cap, if relevant = pi x r^2 = 3.14159 x 16 = 50.27 = 0.01A   Or, close enough.   Peter Wieck Melrose Park, PA

amdx <nojunk@knology.net>: Jun 26 11:24AM -0500 On 6/26/2018 10:54 AM, JBI wrote:   > You're at the same place I was originally when I did the calculation, > which made me question whether or not I should take the square root of > the area     I think the mistake your making is the 26 is already in cm^2, no need to take the square root. Just 26 x 0.2 = 5.2 amps.   OR, another way, your anode is 100mm x 8mm dia or 100mm x 25mm, convert to cm for 10cm x 2.5cm this equals 25cm^2. 25cm^2 x 0.2 amps = 5 amps.     and then multiply that by current density.  When I took the

"Miguel Giménez" <me@privacy.net>: Jun 26 12:51PM +0200 > There are manuals for the 34 and 36 on hif-manuals.com, they skip the 35. Perhaps one of them is close enough. Nothing on hifiengine and electrotanya didn't turn up in the results so that is about all I got.   > You have to register to get it from hifi-manuals but it is easy and they do nothing, like install anything or spam you, I have had no problem like that at all. You might get just one email with an activation code or page or something and that's it.   Thank you for the information. Downloading is currently disabled, I'll check from time to time. Externally they are very similar.   -- Saludos Miguel Giménez

jurb6006@gmail.com: Jun 25 01:41PM -0700 I joined not too long ago. Originally I got into Tekscopes@groups.io. then Tekscopes2, and then made my own, TestgearNotTekScopes.   they are pretty strict about content, so there is no politics or any of that, but it has proven to be a valuable resource for those who work on Tek scopes, and most other things due to my group.   The site does not require anything, but you can also be thrown out if you post off topic things. They don't spam you or bug you to update your browser, FF15 works just fine. If you got something off topic to discuss there are email links for the members. At first you might think you are getting spammed because they send you an email about all the new posts, go to "subscription" and tell it you want a daily summary. That way you just get what has been updated in the groups once a day.   I will not allow much discussion of Tek scopes on TestgearNotTekScopes because I do not want to fragment that group of dedicated Tek scope aficionados.   There is alot of test gear out there that is not a Tek scope, so to discuss that without any bullshit, join. No politics, no insults especially about anyone's technical expertise, if you know more, reveal it or STFU.   I mention this because I figure that out there people do work on test equipment and don't want to wade through a million posts about Obama, Trump, Clintons, the TPP, NAFTA and all that shit. There are places for that.   If you want to get technical, go for it, just remember it is moderated, not like here.   I allow some leeway in testgear, for example, if you work on tape decks or tuners or whatever, an amp or receiver can be considered a test unit as it is needed to test the unit. A monitor for example, if you work on PCs, well that is necessary, if you work on VCRs (some still do) then a video monitor or TV could be testgear.   If consumer electronics goes too big, I will split it off to another group but that remains to be seen. Also, I might be looking for moderators soon. If nothing else just to approve new members' first posts. After that they are not moderated, but you can tell if it is spam or whatever. If it is objectionable then don't approve it. I'll take care of the banning and plonking.   So maybe try it out. You can pick no email if you want, I don't and any moderators shouldn't because they have to approve posts from new members.   If anyone wants and can't find it I will provide direct links.   Your call.

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"Ron D." <ron.dozier@gmail.com>: Jun 24 05:59PM -0700 Yep, Fluke, Keysight (formerly Agilent/HP) and Keithley which is now Tek or Tektronix are like the goto options.   These http://www.ni.com/pdf/product-flyers/digital-multimeters.pdf may prove to be a unique addition.

captainvideo462009@gmail.com: Jun 24 10:24AM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   Hey guys I really need some more help with this one. It's on the bench and even though I'm working on it my wife is flipping out over the entertainment center all torn apart in the living room. But that's a woman for you, can't appreciate the beauty of a repaired 1974 receiver...   Anyway in looking at the schematic I can see that there is a 6 volt winding referenced to ground. The blue 6 volt transformer wire goes through a 5 amp fuse the output of which directly feeds AC to a bunch of lamps in parallel. The output of the fuse also feeds a rectifier and filter which then feeds DC to some other lamps through some other switches. I just can't make any sense out of it.   For one thing although I can see a multi pole switch feeding individual lamps and I'm assuming they are indicators I can't tell for sure which lamps are for which function, (panel lights or indicators) and so I'm not certain where to jump because I can't tell which lamps would need to powered by AC or DC. Most of the ones that seem to be indicators such as phono, tape, etc. seem to light now and it would be nice to retain that after jumping out whatever I need to to restore the other lights.   Another weird thing which is also troubling is that every once in awhile the signal meter seems to illuminate although it doesn't seem like it's fully bright and there is never any signal level response on it. I never had trouble with that either. Can one of you guys please help me with determining where to "jump" the switch and get all the lamps working? Then I'll have to figure out this signal meter problem. Thanks, Lenny

Chuck <ch@dejanews.net>: Jun 24 04:09PM -0500 On Sun, 24 Jun 2018 10:24:54 -0700 (PDT), captainvideo462009@gmail.com wrote:     >Anyway in looking at the schematic I can see that there is a 6 volt winding referenced to ground. The blue 6 volt transformer wire goes through a 5 amp fuse the output of which directly feeds AC to a bunch of lamps in parallel. The output of the fuse also feeds a rectifier and filter which then feeds DC to some other lamps through some other switches. I just can't make any sense out of it.   >For one thing although I can see a multi pole switch feeding individual lamps and I'm assuming they are indicators I can't tell for sure which lamps are for which function, (panel lights or indicators) and so I'm not certain where to jump because I can't tell which lamps would need to powered by AC or DC. Most of the ones that seem to be indicators such as phono, tape, etc. seem to light now and it would be nice to retain that after jumping out whatever I need to to restore the other lights.   >Another weird thing which is also troubling is that every once in awhile the signal meter seems to illuminate although it doesn't seem like it's fully bright and there is never any signal level response on it. I never had trouble with that either. Can one of you guys please help me with determining where to "jump" the switch and get all the lamps working? Then I'll have to figure out this signal meter problem. Thanks, Lenny Lenny, Jumper Pin 02 on F-1483 board to the end of R0118 that goes to PL01. Jumper the B+ end of PL707 to B+ end of PL713. Jumper B+ end of PL 701 to B+ end of PL704. This should allow all lights except for mode ones to light. I'd put a 100 watt light bulb in series with the AC in just in case I screwed up. As a retiree, my mind isn't what it once was. Good luck.

John-Del <ohger1s@gmail.com>: Jun 24 03:37PM -0700 On Sunday, June 24, 2018 at 5:09:26 PM UTC-4, Chuck wrote: > to light. I'd put a 100 watt light bulb in series with the AC in just > in case I screwed up. As a retiree, my mind isn't what it once was. > Good luck.     Hmmmm... I would probably drill holes in the backs of all the gauges and just globally light up the entire inside of the receiver...   Lenny, I've got about a dozen receivers abandoned from repairs over the years and some of them are quite vintage, although none are quad to my recollection. If you want one, stop by next time you're coming through CT and you can pick out what you want.

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The Real Bev <bashley101@gmail.com>: Jun 24 08:59AM -0700 On 06/22/2018 11:33 PM, N_Cook wrote:   > At least you don't need f.c.ing javascript and the inordinate amount of > crap that comes with it , to view just a couple of kbytes of info. > Remember Google bought Deja-news and then proceeded to bastardise usenet.   I had real hopes at first... Their original search function was really nice, and then they crippled it. Like google seems to do with everything. I really miss Picasa.     -- Cheers, Bev "The almost universal access to higher education here in the US has ruined a lot of potentially good manual laborers." -- Bob Hunt

Chuck <ch@dejanews.net>: Jun 23 02:31PM -0500 On Fri, 22 Jun 2018 13:35:43 -0700 (PDT), captainvideo462009@gmail.com wrote:   >This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in >parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny Lenny, See my answer on the Yahoo tv-repair group. Chuck

captainvideo462009@gmail.com: Jun 24 12:57AM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   « Back to Inbox ‹ Newer 3 of about 86 Older › Expand all messages Expand all Print conversation Print Open conversation in new window New window Sansui QRS5500 receiver Inbox Unstarred Klem Kedidelhopper Fri, Jun 22, 2018 at 4:32 PM 2 hidden messages – Show Unstarred chuck3564@yahoo.com [tv-repair] Sat, Jun 23, 2018 at 2:29 PM Add star Klem Kedidelhopper<captainvideo462009@gmail.com> Sat, Jun 23, 2018 at 7:39 PM To: tv-repair@yahoogroups.com Reply | Reply to all | Forward | Print | Delete | Show original I had actually thought of that. It wouldn't be a problem if the lamps were on for each mode. I just wish that I could see the burned section of the switch but it's an impossible jungle of wires.   Two weeks ago before I knew about the lighting problem I picked up a 5500 to use for parts, because my quad section has never worked and I have been thinking that it would be nice to swap a couple o boards and see what happens. So I have a switch however there is no way I'm going to tackle replacing that switch.   I thought o something else. Back in the late 60's and early to mid seventies when VHF TV tuners were built with multisection switches I used to run across a fair number of them that just wouldn't respond to a good cleaning with a silicon based tuner cleaner. Then they came out with "Blue Stuff". As long as you didn't spray it on the neutralizing capacitors it was a miracle of bringing back intermittent tuners to life once again. I So I thought I might try degreasing the switch first and then give it a good cleaning with Blue stuff. and then see what happens. Probably nothing will come of it but it doesn't hurt to try I guess. Lenny

Randy Day <randy.day@sasktel.netx>: Jun 23 11:22AM -0600 I'm looking for recommendations on a computer-controlled multimeter to automate a test procedure. I'd like to be able to have the computer select voltage, resistance, etc., choose various ranges in each, and transmit readings to a PC.   I see a lot of units that communicate, but I'm unclear whether they allow functions and ranges to be set, or whether they just transmit results from the range selected on the front dial.   The one unusual requirement is a high resistance range (e.g. 2000Mohm). ACV/DCV/ohms ranges can otherwise be similar to regular handheld units.   Any suggestions?

John Larkin <jjlarkin@highlandtechnology.com>: Jun 23 11:14AM -0700 On Sat, 23 Jun 2018 11:22:06 -0600, Randy Day <randy.day@sasktel.netx> wrote:   >2000Mohm). ACV/DCV/ohms ranges can otherwise be similar to >regular handheld units.   >Any suggestions?   We use a lot of Keithley and Fluke benchtop DVMs in test sets, with ethernet or USB interface. They can set anything under remote control except for switching between the front and rear-panel inputs.   I prefer the Fluke 8845A. It's more stable at microvolt levels, does good AC measurements, and is EMI harder than the Keithleys.   It only measures 100M ohms max, but you could do some simple hack to measure gigohms.   There are cheap handhelds with interfaces, but the interface won't turn the big range knob.   There are also cheap benchtop DVMs, typically Chinese. Might be good enough.         --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Peter Gierschner <oskarx@gmx.de>: Jun 23 09:02PM +0200 Am 23.06.2018 um 19:22 schrieb Randy Day: > 2000Mohm). ACV/DCV/ohms ranges can otherwise be similar to > regular handheld units.   > Any suggestions?   Here   https://www-user.tu-chemnitz.de/~heha/hs/UNI-T/   are some programs for UNI-T or similar multimeters.   peter

John Robertson <spam@flippers.com>: Jun 23 12:28PM -0700 On 2018/06/23 10:22 AM, Randy Day wrote: > 2000Mohm). ACV/DCV/ohms ranges can otherwise be similar to > regular handheld units.   > Any suggestions?   Mooshimeter? Doesn't do resistance, but for remote monitoring of voltage and current it is handy...and perhaps the designer is interested in expanding it to resistance.   https://moosh.im/mooshimeter/   Handy tool!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Randy Day <randy.day@sasktel.netx>: Jun 23 07:01PM -0600 In article <pgm5g8$ad1$1@news.albasani.net>, oskarx@gmx.de says...   [snip]     > https://www-user.tu-chemnitz.de/~heha/hs/UNI-T/   > are some programs for UNI-T or similar multimeters.   > peter   Bookmarked, thanks!   Actually we have a Uni-T at the shop; can't remember the model number, though. Given the price of benchtop units that John mentioned, maybe I can run multiple cheap datalogger units switched in with relays; I wondered if there might be a low-cost all-in-one alternative I hadn't seen.

Randy Day <randy.day@sasktel.netx>: Jun 23 07:11PM -0600 In article <rKednWCtDNPrArPGnZ2dnUU7-WfNnZ2d@giganews.com>, spam@flippers.com says...   [snip]   > https://moosh.im/mooshimeter/   > Handy tool!   > John :-#)#   Wireless doesn't really offer an advantage in this instance, but it's an interesting device.   Thanks.

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captainvideo462009@gmail.com: Jun 22 01:35PM -0700 This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny

jurb6006@gmail.com: Jun 22 06:36PM -0700 I hope you mean a QRX, not QRS. They got it at hifiengine, it shows a fuse for the dial lamps, F 01, 5 amps. It also feeds a rectifier for about an 8 volt source that feeds the stereo light, also off the fuse. While at this age those lamps may have blown one at a time by now, you would have noticed it.   the cap in the protection, the failure mode is weird. They are usually 10 volts and sometimes go right across B to E of a transistor so they never charge more than like a half a volt. they get leakier and leakier over time. They are usually fed by a high value resistor, like 100K or more. I didn't look at that part of the circuit but since it is fine, fukit.   Not a badly designed piece. Full comp outputs, current source instead of a bootstrap, DC coupled. Theoretical peak RMS short tem power is 76.5 WPC. The rating is 30, so splitting the difference I would say you got about 1.5 dB or so dynamic headroom. It is probably over 3 dB for a couple milliseconds, but in real life not so much.   Tuner is pretty conventional, uses ceramic filters but still a standard ratio detector. No pilot cancel, but all that doesn't mean it doesn't sound good.   Tone controls OK, filters only 6 dB, don't use the filters. he variomatrix looks like a good thing, like Marantz varimatrix I would guess. You have control over the L+R attenuatoin in the rear.   I don't see amp strapping in it though, or pre out/main in.   Enough commentary, if it is QRX the manual is at hifiengine.com. It is probably ready for the FM to be tweaked, but it might not be so bad. Other than fixing the lights, if all the channels sound good I don't recommend anything. You could go in with an ESR meter and replace caps if you feel like it. Just never short the speaker wires because it has no current limiting at all.

"David Farber" <farberbear.unspam@aol.com>: Jun 22 08:33PM -0700 > don't recommend anything. You could go in with an ESR meter and > replace caps if you feel like it. Just never short the speaker wires > because it has no current limiting at all.   Just a hunch here but I remember there were many Sansui models manufactured in that era that had faulty rotary function selector switches. The result was that the panel lights would flicker or go out completely. No amount of switch cleaning would restore them to good health. If you wiggle the function selector switch, do the lights flicker or does the meter function momentarily?   -- David Farber Los Osos, CA

captainvideo462009@gmail.com: Jun 23 04:02AM -0700 > This is my own receiver. Last year it started taking longer and longer for the protection relay to activate and turn on the speakers I finally took it out of service. I recall that it had no other problems that were evident. I had posted this problem at that time and I think that it was Chuck up in Canada who nailed it immediately. He recommended changing C6 on the protection board and .that resolved the protect relay problem. Now however there is another problem that I never had before. Most of the dial lights including the signal meter light are out and that meter also seems to be inoperative as well. I never had any trouble with any lighting or the signal meter on this receiver. This is a big quadrophonic receiver. The switching is done through the main selector switch and it's a nightmare to get to. A real rats nest. Does anyone who has worked on these recall any common problems with lighting on one of these? I suspect a ground problem because so many of these lamps are in parallel but it's so crowded in that area you can't see anything. I Really appreciate any help. Lenny   I think that I know what the problem is. I first sprayed the main selector switch with a silicon based cleaner that contains a mild lubricant, figuring that one of the phenolic wafer sections in the .switch that was switching the power for the lamps perhaps was dirty. This stuff evaporates quickly and it didn't solve the problem. After more fruitless probing, in a last ditch effort I hit all the segments of the switch with No Ox. This stuff is like "Blue Stuff" but a bit more oily. I worked the switch to distribute the material and then powered the unit on. No Ox works wonders with controls and switches but it is some what messy.To my utter dismay I noticed smoke coming off part of the selector switch. (This was probably from the sector that is switching the high current lamp power. I now have to pull the front panel and hope that I then will be able to get a better eyeball of the selector switch. If the section is burned though I don't know what I could possibly do though. A selector switch problem....... My worst fear becomes a reality. Is today the thirteeth by any chance? Lenny   On 6/22/18, Ardell Faul ardellfaul@gmail.com [tv-repair] - Show quoted text - Quick Reply To: tv-repair@yahoogroups.com

jurb6006@gmail.com: Jun 23 06:40AM -0700 Jump out the switch and see if it blows the 5 amp fuse.   I think 5 amps is a bit much for that type of switch.

Cursitor Doom <curd@notformail.com>: Jun 22 08:14PM https://www.diybanter.com/       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jun 22 06:44PM -0400 On 06/22/18 16:14, Cursitor Doom wrote: > https://www.diybanter.com/   Don't knock it. My sig block plus all the sci.electronics.design scraping sites is a very effective SEO technique.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

N_Cook <diverse@tcp.co.uk>: Jun 23 07:33AM +0100 On 22/06/2018 21:14, Cursitor Doom wrote: > https://www.diybanter.com/   At least you don't need f.c.ing javascript and the inordinate amount of crap that comes with it , to view just a couple of kbytes of info. Remember Google bought Deja-news and then proceeded to bastardise usenet.

Allodoxaphobia <knock_yourself_out@example.net>: Jun 23 12:37PM On Sat, 23 Jun 2018 07:33:39 +0100, N_Cook wrote:   > At least you don't need f.c.ing javascript and the inordinate amount of > crap that comes with it , to view just a couple of kbytes of info. > Remember Google bought Deja-news and then proceeded to bastardise usenet.   See my long-time usenet .sig   Jonesy -- Marvin L Jones | Marvin | W3DHJ.net | linux 38.238N 104.547W | @ jonz.net | Jonesy | FreeBSD * Killfiling google & XXXXbanter.com: jonz.net/ng.htm

N_Cook <diverse@tcp.co.uk>: Jun 23 07:49AM +0100 Cheapo no-name/rebadgeable chinese video projector. Uses really only an analogue IC to process baseband video and sound, and mainly a TSUMV56RBUT-Z1 processor (LCD driver+ more) , only info in chinese. But mention of Android OS emerges in the otherwise chinese script. So is it just a mobile phone LCD display in a box , changed firmware to handle HDMI and SVGA inputs,rejigged pcb, plus high power LED floodlamp instead of backlight, compound lens, mirror,2 fresnels , one pivoted for keystone, and a radial fan for relative quietness, and a small speaker?

bruce2bowser@gmail.com: Jun 23 02:18AM -0700 On Saturday, June 23, 2018 at 2:49:06 AM UTC-4, N_Cook wrote: > handle HDMI and SVGA inputs,rejigged pcb, plus high power LED floodlamp > instead of backlight, compound lens, mirror,2 fresnels , one pivoted for > keystone, and a radial fan for relative quietness, and a small speaker?   Cicret Bracelet Phone?   -- https://www.youtube.com/watch?v=9J7GpVQCfms

ggherold@gmail.com: Jun 22 10:15AM -0700 On Friday, June 22, 2018 at 10:28:46 AM UTC-4, Phil Hobbs wrote: > > (I use a lot of BNC to dual banana plug adapters.. then I can watch > > the fast stuff on the 'scope at the same time.)   > Ah. Those put a lot of torque on the solder joints, of course. The solder joints look fine... OK I just retouched them... same deal, (just as well cause I already spent $30 on the part Jeff linked to. :^)   When I replace it, I'll butcher the old one and see if I can find anything.   George H.

Jeff Liebermann <jeffl@cruzio.com>: Jun 22 10:44AM -0700 >The solder joints look fine... OK I just retouched them... same deal, >(just as well cause I already spent $30 on the part Jeff linked to. :^)   If the soldering is fine, then my best guess(tm) is that there's a broken spot weld or press fit connection between the pin that goes into the PCB, and the actual connection to the brass threads inside the banana jack. If I'm right, the pin might fall out when you unsolder it.   >When I replace it, I'll butcher the old one and see if I can find anything.   Umm... it's called an autopsy.   -- 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

"jfeng@my-deja.com" <jfeng@my-deja.com>: Jun 22 01:05PM -0700 > (I use a lot of BNC to dual banana plug adapters.. then I can watch > the fast stuff on the 'scope at the same time.)   > GH   Banana jacks are so simple that, in the absence of obvious physical abuse, I find it hard to believe that it is intermittently faulty. I would try soldering test leads directly to the lugs; when that does not fix the problem, I would look somewhere downstream like a crack in a pc board or a cold solder joint.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jun 22 06:41PM -0400 On 06/22/18 11:50, Jeff Liebermann wrote: > "Also, many old IFRs are having power supply problems. If anyone > would like to do an article on troubleshooting and repair we'd > be happy to put it here."   I power a lot of prototypes from random laptop bricks with eBay SMPSes hung on them. The eBay units are generally quite okay as long as you derate their output current by about 3X.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jun 22 06:48PM -0400 On 06/22/18 18:41, Phil Hobbs wrote:   > I power a lot of prototypes from random laptop bricks with eBay SMPSes > hung on them.  The eBay units are generally quite okay as long as you > derate their output current by about 3X.   I should add that you can make negative supplies out of an eBay buck regulator module by applying input power to +IN, grounding +OUT, and taking the negative output between there and the original common ground.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Phil Allison <pallison49@gmail.com>: Jun 22 04:47PM -0700 > I tried squeezing them in some, it's maybe a bit better, but no one > wants even a bit of flaky in their test gear. Any ideas? (about how I might > fix it.)   ** You have tried using cleaning fluid ??? PCB cleaner or even WD40 will do.   An old handkerchief pushed home with a small drill bit is one way to introduce some fluid and clean the inside surfaces.     ..... Phil

ggherold@gmail.com: Jun 22 06:42PM -0700 On Friday, June 22, 2018 at 7:47:57 PM UTC-4, Phil Allison wrote:   > PCB cleaner or even WD40 will do.   > An old handkerchief pushed home with a small drill bit is one way to introduce some fluid and clean the inside surfaces.   > ..... Phil   No! I wiped 'em with IPA and a wooden cotton swab thing. I'm away from the lab for a while so I won't be able to try some other cleaner til I return.   George H.

amdx <nojunk@knology.net>: Jun 22 09:22PM -0500 On 6/22/2018 10:05 AM, Tim R wrote:   > I agree with that but you're using a misleading singular.   > THAT.......is THE problem.......... falsely implies only one thing is wrong. I've been fooled a number of times because two things were bad simultaneously. Sometimes one caused the other but sometimes it's just random.   > In fact there is no theoretical limit to how many things can go wrong at once.   Oh, sounds like you worked on the first NAP VCR switching power supplies! The parts dept finally came out with a repair kit, I think it contained 8 parts, and it was strongly suggested you replace all parts before applying power.   Mikek

M Philbrook <jamie_ka1lpa@charter.net>: Jun 22 05:35PM -0400 In article <39vkid50vpmlm75uee40akmrrkjq5r25tg@4ax.com>, jeffl@cruzio.com says... > consider more useful. Wavetek or SSI 3000A. I think I paid about > $300.   > Gotta run...   I have two them with the 1G option, love'm

jurb6006@gmail.com: Jun 22 09:51AM -0700 There are manuals for the 34 and 36 on hif-manuals.com, they skip the 35. Perhaps one of them is close enough. Nothing on hifiengine and electrotanya didn't turn up in the results so that is about all I got.   You have to register to get it from hifi-manuals but it is easy and they do nothing, like install anything or spam you, I have had no problem like that at all. You might get just one email with an activation code or page or something and that's it.

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