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Old 9th Nov 2017, 7:40 pm   #1
nageeb_
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Thumbs up My Sanyo VTC-R4ME Multi-System Betacord

I've recently taken up the task of resurrecting this old gem: Sanyo VTC-R4ME.

Originally purchased in 1983 in Saudi Arabia, this unit worked pretty much flawlessly until the late 90's. I'm currently diagnosing some issues with a board which I believe is a secondary power supply or power regulator board.

I'm being very cautious as I still haven't been able to find any service manuals or schematics on this model.

I'm posting this mainly just to show off this old reliable beauty and the insane amount of work that went into it's construction. Having said that, if anyone does happen to know where I could get my hands on any kind of documentation, I'd appreciate it
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Old 9th Nov 2017, 8:54 pm   #2
dj_fivos_sak
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Really nice machine. Here's my 1981 VTC 5350 which looks very simlar but different mechanism. Did you get the clock display to light up?
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Old 10th Nov 2017, 7:00 pm   #3
Sanbeta
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Whilst I've never heard or seen that particular model you can clearly see the deck side is a 5000 clone.
I have found on the hundreds of Sanyo's I've repaired and refurbed that usually high ESR caps is the most common issue after long periods powered up. This is mainly in the clock vacuum flurescent display area of the PSU.
I would check over all the caps and it should alleviate any issues with that area anyways.
Thanks for sharing those images. Interesting indeed.

...................Kevin
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Old 10th Nov 2017, 7:21 pm   #4
dj_fivos_sak
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

This model looks unique. The top cover looks like the VTC 5300/5400 (actually 5350 because of the woodgrain finish) but the mechanism is the same as the 5000. So quiet a bit of a hybrid deck. Notice the large number of capstan/drum servo adjustment pots for PAL/SECAM and NTSC BII and BIII speeds!

Fivos
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Old 10th Nov 2017, 7:51 pm   #5
nageeb_
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

The issue I'm having seems to be related to power (thankfully). When I plug it in, nothing happens. My main PSU seems to be ok (surprisingly) and has a connector which outputs 2x 12v/0v lines and a 23VAC line to a secondary regulator board (PS2 in the photo above). That board then has headers that go to the various modules for tuner control, modulation, front panel, motor etc. The PS2 board has 2 test points for 9V and 12V and I've found that my 9V power is dead. Without a service manual or circuit diagram, I'm left to simply work backwards from there

Quote:
Originally Posted by Sanbeta View Post
I have found on the hundreds of Sanyo's I've repaired and refurbed that usually high ESR caps is the most common issue after long periods powered up. This is mainly in the clock vacuum flurescent display area of the PSU.
I would check over all the caps and it should alleviate any issues with that area anyways.
I've tried replacing the usual suspects, recapped the entire PS2 board and replaced a 9v regulator and a motor driver transistor but that didn't fix anything. I'm now working my way back along the 9v line and checking the diodes and resistors as I go. At this rate, it's entirely possible that I'll end up just rebuilding the entire board with new components .

I've found 2 sites which claim to have the manuals and circuit diagrams for the VTC-R4ME but neither of them can give me any assurances as to the quality of the documentation, and for $100USD I'm not willing to risk it at this point.
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Old 10th Nov 2017, 11:49 pm   #6
dj_fivos_sak
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Did you trace back the 9V supply yet? I found this link for the manual but I have no clue if it's legit or not:
http://www.manualuniverse.com/manage...R4ME&xmrcG=171

Regards,
Fivos
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Old 11th Nov 2017, 12:22 am   #7
nageeb_
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Still working on it... I'm getting 9v at the regulator, but somewhere between the regulator and the headers, it's getting lost. Definitely don't have 9v at the test point.

Thanks for that link... I emailed those guys yesterday. They're one of two sites that I found who claim to be able to get the manuals, however they're not scanned yet and they can't guarantee the quality or the contents. Not the kind of gamble that's worth $75... Not yet, at least.
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Old 11th Nov 2017, 12:55 am   #8
dj_fivos_sak
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Let me know if you get a reply from them as I need the manual for the VTC 9455 multi system Beta. As for the power supply of your R4ME, is it 110/220V selectable or automatic?

Fivos
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Old 16th Nov 2017, 8:33 pm   #9
Sanbeta
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

I had the same nightmare with a multi standard Sony SLT30me which not only had really high ESR caps but it wiped out a coil and ceramic caps too. Which was a ****** pain.
That's the thing when they are designed for multi regions.
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Old 17th Nov 2017, 6:52 pm   #10
nageeb_
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

I've recapped the entire secondary power supply board but didn't even consider ESR. Is there something special I should have done other than simply replace the caps 1-for-1 based on the original ones?

I've also replaced a 9v regulator and one of the BJTs but still no luck. I don't have a meter capable of testing inductance, but I've done basic testing of the coils (metered resistance, checked for shorts or coil failure) and they seem to be working fine.

This repair is definitely proving to be a learning experience

Quote:
Originally Posted by dj_fivos_sak View Post
As for the power supply of your R4ME, is it 110/220V selectable or automatic?
It's automatic.
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Old 20th Nov 2017, 5:22 pm   #11
dj_fivos_sak
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Quote:
Originally Posted by Sanbeta View Post
I had the same nightmare with a multi standard Sony SLT30me which not only had really high ESR caps but it wiped out a coil and ceramic caps too. Which was a ****** pain.
That's the thing when they are designed for multi regions.
True. Multi system VCRs are a pain in the butt when it comes to electronic issues. My VTC 9455's Chroma circuit is acting strange. Similar issues with my National NV-7500 too.
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Old 21st Nov 2017, 11:09 am   #12
Maarten
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

You say you replaced the caps based on te original ones, so that would be all relevant parameters including esr/impedance. Even if you forgot about esr, that would most of the time mean the capactior would break down sooner rather than later but the set should work for a while. The best course of action is probably to track down the missing 9V.
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Old 2nd Feb 2018, 12:19 am   #13
dj_fivos_sak
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Default Re: My Sanyo VTC-R4ME Multi-System Betacord

Hi there. Do you have any luck restoring this machine? From your pictures, I figured out that it's actually using a switching power supply on the secondary side after the main power transformer, just like my VTC 9455. Also, I noticed it has a Texas Instruments TL494CN power IC, just like the Sony SL-C7 and the VTC 9455. So my suspicion is that this IC is toast. I have attached part of the schematic of the SL-C7.

Regards,

Fivos
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