|
Update: I disassembled the whole thing, gave everything but the tube a generous bath with 99% IPA and a paint brush. Cleaned up really nice, and there is no sign of any blown up components. It must have lived in a really dirty environment.
Upon initial inspection there are no leaky caps surprisingly. There's some differences in my unit from the pics HelloVoltage posted. Board B has conformal coating surrounding the pins on the IC's and capacitors, and I suspect that's hiding some cap leakage, but thankfully it protected the traces. A few days after washing it I'm starting to smell something fishy (electrolyte) so I will be replacing most of the caps. I tested all of them with my ESR meter and most of them are shot or close to the limit. The giant caps on board D1 are testing as good so I might keep those if they aren't leaking. Does anyone know if I should bother replacing all the really tiny bipolar electrolytic caps? I don't really know how to identify the value, some just say "10" and some say nothing at all. My ESR meter can't read them either because they are too small, it just shows open circuit. In my experience these never really leak or go bad but I'm curious to what you guys will say. Last night I made a list of all the caps, minus those tiny ones. I'll post it later once I confirm there's no mistakes. I'm also gonna pop open the diversity unit again and test all the caps even though they look fine. I'm always so impressed by the quality and engineering of these early 90s electronics, It seems like it was a time where they had to try really hard to fit things into a small package with mostly through-hole components. The smell of electronics from the late 80s-early 90's is heavenly, its definitely a unique to that time period. The PCBs are usually a much darker green and are always covered in lots of flux. Next update I'll try powering it on with the new caps. |
Hi to all,
Hi HelloVoltage, your assortment of XAV-U50 & diversity receivers is impressive! Do you have service manuals for both? Scans? paper? buyable somewhere? i'm interested in the display unit SM (have one), never tried to use it. Any photos of your units in operation; would love to see one working (& i bet all Indextron lovers). @dinorhino : watching your endeavours with interest... Best Regards jhalphen Paris/France |
Hey guys, another update for ya. I replaced all the bad caps in the main TV unit. Some of the large caps where fine so I left them, and the really tiny 1uf caps because they where fine.
Got it powered on using a 16v 4A laptop charger as I heard these run better with a little more juice, also its all I had that could supply enough amps. The TV powered on no issues, no smoke. A white raster appeared and then got squished on the edges (see pic). None of the buttons do anything but I expected that being there's no diversity unit hooked up. Slightly concerned about the weird raster distortion, it's exactly like what you can see in this helpful video at 20:45 https://www.youtube.com/watch?v=rrQWaDT61bc Hoping that with a video signal the distortion will go away. https://drive.google.com/file/d/1sLY...ew?usp=sharing |
Hi to all,
Hi Dinorhino, Congrats! on getting the display unit to show a raster. How many electrolytics needed changing? All "normal" Caps (with leads) or some Surface Mounted Devices? Do you know where to inject Video & which format? (Composite, RGB, VGA...) I really wish HelloVoltage would help with more tech data, schematics, personal experience, etc. Best Regards jhalphen Paris/France |
Hi there, I replaced about 60 Capacitors in the tv unit, and around 30 in the diversity unit. All through hole caps.
Today I hooked up my diversity unit to the tv for the first time, I had to figure out the connections for power. There's 2 ground pins, BATTERY, ACC, and REMOTE, all 3 need to receive 12 volts for the unit to power on. Thankfully the custom cable I made using a old floppy drive ribbon and 26 pin female Centronics connectors was able to handle the current and didn't burn up lol. If you need a cable this is definitely the cheapest and easiest way to do it. Everything powered up fine, but the screen still shows the same white raster, no menu or anything. When I press the buttons it beeps now so that's a good sign the two units are communicating. Maybe its not displaying because I haven't hooked up the pins for the "safety harness" that disables the video display when the car is in drive. But I would assume it should still display the menu so you can tune the radio while driving. Ill try that next but I don't know what kind of signal they are expecting. I would also really appreciate HelloVoltage's input, tell us everything you know please! If HelloVoltage hasn't already, I intend to reverse engineer the connection between the diversity unit and the tv to see what video signals are being passed. But I need a fully functional unit first. Update: Something I forgot to mention is that after the white raster gets "squished" half of it turns grey. I discovered that by adjusting the blanking pot on board B the grey part gets brighter or darker. Board B appears to handle the beam indexing and feeds the amplified video to the neck-board and then the cathode on the CRT. Nothing happened when I tried feeding the B board a video signal into one of its RGB pins either. I also discovered that by disconnecting the photo sensor board from board B, the pin cushion distortion doesn't happen and the white raster fills the whole screen without changing. I suspected maybe the diversity unit was not sending video so I tested the connector with my oscilloscope to find what looked like a video signal and I came across one that sort of looked like a video signal and it changed slightly when changing from TV to VIDEO/WM. Unfortunately while testing I had the tv running for longer than any time before and I heard a small pop and smelled something I can only describe as "too hot electronics" and capacitor juice. So I shut it off and that's as far as I've gotten. I inspected a little and haven't found anything obviously burnt or damaged yet. Checking with a infrared thermometer nothing I can see seems to be getting unreasonably hot, even the vertical output transistor only gets to around 130F If only there was a service manual available. |
VideoKarma Member
Join Date: Dec 2023 Posts: 5 Hi there, I replaced about 60 Capacitors in the tv unit, and around 30 in the diversity unit. All through hole caps. Today I hooked up my diversity unit to the tv for the first time, I had to figure out the connections for power. There's 2 ground pins, BATTERY, ACC, and REMOTE, all 3 need to receive 12 volts for the unit to power on. Thankfully the custom cable I made using a old floppy drive ribbon and 26 pin female Centronics connectors was able to handle the current and didn't burn up lol. If you need a cable this is definitely the cheapest and easiest way to do it. Everything powered up fine, but the screen still shows the same white raster, no menu or anything. When I press the buttons it beeps now so that's a good sign the two units are communicating. I have 8 of the displays working. Only using 1 of the diversity units for all though. I have 7 displays consistently working. Only been testing with 1 of my diversity units though. >>>>this suggests your divirsity unit is not fully repaired. Do you see/hear the relay actuate? Maybe its not displaying because I haven't hooked up the pins for the "safety harness" that disables the video display when the car is in drive. But I would assume it should still display the menu so you can tune the radio while driving. Ill try that next but I don't know what kind of signal they are expecting. >>>>>safety harness/connector_jumps is/are not necessary. I would also really appreciate HelloVoltage's input, tell us everything you know please! If HelloVoltage hasn't already, I intend to reverse engineer the connection between the diversity unit and the tv to see what video signals are being passed. But I need a fully functional unit first. >>>>video is ntsc. Not sure if it's the 7(6?) line down version from japan. It's ntsc either way for testing. Update: Something I forgot to mention is that after the white raster gets "squished" half of it turns grey. I discovered that by adjusting the blanking pot on board B the grey part gets brighter or darker. Board B appears to handle the beam indexing and feeds the amplified video to the neck-board and then the cathode on the CRT. >>>>> avoid messing with pots. Nothing happened when I tried feeding the B board a video signal into one of its RGB pins either. >>>>>Please point out what you thought you were doing on the "b" board. I have so far only been able to partially batch in a composite signal without the divirsity unit. see : (http://www.videokarma.org/showpost.p...&postcount=178) image 6. Injecting rgb looks to be possible, but not yet successful. Not much attempt though I also discovered that by disconnecting the photo sensor board from board B, the pin cushion distortion doesn't happen and the white raster fills the whole screen without changing. >>>>never tried that I suspected maybe the diversity unit was not sending video so I tested the connector with my oscilloscope to find what looked like a video signal and I came across one that sort of looked like a video signal and it changed slightly when changing from TV to VIDEO/WM. >>>>do you have photo of your divirsity unit? Unfortunately while testing I had the tv running for longer than any time before and I heard a small pop| >>>>ouch and smelled something I can only describe as "too hot electronics" and capacitor juice. So I shut it off and that's as far as I've gotten. I inspected a little and haven't found anything obviously burnt or damaged yet. Checking with a infrared thermometer nothing I can see seems to be getting unreasonably hot, even the vertical output transistor only gets to around 130F If only there was a service manual available. Last edited by dinorhino; 03-20-2024 at 11:10 PM. Reply With Quote I have no service manual. Just went through slowly cleaning vias, replacing caps, controlling power. Only mistake so far was the assumption about the proprietary composite jack which is also 3.5mm. |
@dinorhino
I just looked at your photo hosted on google. Your board B and board A for xav-u50 are looking significantly different from the a&b boards on my xav-u50's More photos please. More photos please all. https://i.imgur.com/gAKTri1.jpeg one of my xav-u50 |
Hi there, it's been a while since I've checked in on this thread. The indextron is still disassembled on my bench so I took some pics for you. I haven't attempted to power it on since last time.
I didn't replace every capacitor on either the diversity unit or the tv unit, I left the really tiny non polar caps and really large high voltage caps, maybe this was a mistake. I did test every original cap with a ESR meter and they all tested well within spec. The diversity unit does operate the relay when powered on. I'm using a 16V 4.5A laptop charger to power both the diversity unit and tv. The voltage drops to ~14v under load IIRC. I had wondered if this was enough to power it, I don't have a good way of measuring the current draw but the charger brick stays relatively cool. I haven't actually tested the audio outputs yet to see if the tuner is functioning... I want to finish this project to make room on my bench, I know if I put it back together now I'll probably never come back and finish it LOL HelloVoltage, any information you can give me on what you had to repair and replace on either unit, please share! I'm a novice when it comes to CRT's and electronics repair in this context so what you might think is not worth mentioning might be very valuable to me! Thanks for the help so far. Here's some pics https://drive.google.com/file/d/1uMp...ew?usp=sharing https://drive.google.com/file/d/158Y...ew?usp=sharing |
Hi to all,
Hope i'm not "broadcasting old news" but found this Sony KVX-370 Indextron demo on YouTube (7min 13") from 4 years ago. Guy purchased a NIB unit & recapped it before any tryout and it works. Good views of the internal construction & circuit boards. Still photos would help documenting future repairs. https://youtu.be/9mGqyCtXyhA?si=lN7bm4yUzoPKERts Best Regards jhalphen Paris/France |
[QUOTE=dinorhino;3261915
I left the really tiny non polar caps and really large high voltage caps, maybe this was a mistake. I did test every original cap with a ESR meter and they all tested well within spec. [/QUOTE] My large caps leaked out fierce on the first diversity unit I opened up, most trace repair was in that relay area. [QUOTE=dinorhino;3261915 I'm using a 16V 4.5A laptop charger to power both the diversity unit and tv. [/QUOTE] I use just the 12v rail of an atx power supply. (amperage permitting)That should be enough as these are automotive electronics. Quote:
|
Quote:
I thought it been well covered by now. |
Hi to All,
Hi HelloVoltage, I'm the person who gave everybody the KVX-370 service manual about 20 years ago. The B&W Scans (other than schematics) are of very poor quality with no grey scale. I was just suggesting that color snapshots of the hi-def YouTube video would be a good adjunct to the service manual. Best Regards jhalphen Paris/France |
jhalphen
do you know if any scans of the boards have been made with part overlay? if not I can. Is there a preferred software for such ? |
are there archival scans of any of this "out there" that any of you know of?
https://i.imgur.com/pjGdr7v.jpeg |
Hi to All,
Hi HelloVoltage, Documents shown in your photo are not available anywhere (to my knowledge) as good quality scans. Overlays: i just looked at the service manual, component placements are identified on the various printed circuit board. not great quality, but usable. Sorry, can't post an example because of ridiculously low forum size limits (and i'm too lazy to subscribe to an outboard hosting service). Creating new overlays for the KVX-370 would be a considerable task and not necessary (in my opinion). However, i have never seen any tech data concerning the car Indextrons (XKV-55, ...) or diversity receivers. Best Regards jhalphen Paris/France |
I have been on a binge of trying to fix these things.
the CX22011 has become unobtanium at this point, and I ventured down the path of re-engineering that power supply before ADHD brain took over and i sidelined the project. Trying to make something that still operates within the parameters of the original so you can still get the synchronized ramp for the parabola is a bit... difficult. The reference point isnt common anymore for newer PWM ICs. I need to figure out how to adapt without changing the loop gain, aka stability of the overall circuit design. I wished the actual SV1 and SV2 schematics were out there. |
Quote:
|
Hi to all,
Hi mbates 14, Photos of the Sony KVX-370 SMPS PCB.: worth a shot : try posting a request on ARF's TV section and flag @AC. Andy is a world class expert on KVX-370 indextrons, he's repaired many over the years for various collectors including myself. ARF TV : https://antiqueradios.com/forums/viewforum.php?f=3 If you ask nicely, he may have some archived photos of the PCBs while he was repairing them. He departed VK a few years ago for personal reasons. I've never managed to find an original Sony paper copy of the KVX-370 service manual. Looking on Buyee Japan shopping site for the KV-4SV2 yields this : https://buyee.jp/item/jdirectitems/a...n_DirectSearch Good Luck! Best Regards jhalphen Paris/France |
| All times are GMT -5. The time now is 07:37 AM. |
Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.