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-   -   Blaupunkt RTV-950 No color on playback? (https://www.digitalfaq.com/forum/vcr-repair/7999-blaupunkt-rtv-950-a.html)

glazuna 05-11-2017 05:59 AM

Blaupunkt RTV-950 No color on playback?
 
1 Attachment(s)
Greetings dear DF members,

I've just purchased an RTV950, which seems to have a problem with colors not being displayed.
I've checked every possible setting, every possible knob. No difference what so ever. It doesn't even have the switch that FS 200 has to turn black&white image, so no worries about that.


The first thing I tried cleaning heads with isoproply alcohol and print paper, got some brown gunk off, but obviously that didn't have anything to do with it.

From what I have read on other posts, it seems most likely, that the caps are to blame. Could anyone point out which board is the one that controls the color?
Let me also point out that everything else seems to work fine, even the front display lights up well enough, not dimm at all.
The unit was supposedly a family kept device, not used that much at all. It can be seen from the buttons being intact as blaupunkts usually have them all worn out, even the remote control seems like new.

VHS tapes used: 2 different SP tapes that play fine on my JVC.
The thing I've noticed is that the recorder does not beep when the tape is inserted, I know that the FS 200 does.

I did also notice that the image has far more detail and sharpness than my JVC 7600, but maybe a bit more noise aswell..

Here is my capture from the RTV 950 -> TBC 1000 - > ATi 600 Diamond PCIe, rendered out as a mov h264, it lost a bit of quality but you will get the point.

The image jitters right when the waterfalls appear on the video, that's the point where I've switched the TBC on blaupunkt OFF. Hence the sudden jump in image.

msgohan 05-14-2017 09:01 AM

Tried letting it warm up?

glazuna 05-14-2017 09:05 AM

I have actually thought of that, but I wasn't sure what warming up ment exactly. My bike needs 5 minutes to warm up. I have no idea how long I'm supposed to have the VCR turned on :'D.

I did let it play for around 5 minutes, maybe 10. And nothing has changed...
It did sit a long time, maybe it would require more running time to see the effect?

msgohan 05-14-2017 09:51 AM

In my case, it took longer than 10 mins to see a difference. Somewhat-okay around 20 mins, then good around 28 min.

http://www.digitalfaq.com/forum/news...html#post49153

glazuna 05-14-2017 01:20 PM

Hmm worth a try, though I think I'm not gonna escape the infamous cap replacement anyways..

Quasipal 05-15-2017 03:31 AM

As far as I know this model does not use any surface mount capacitors - unless this is one area where it does differentiate from the FS200. No colour does sound like an issue on the chroma board so my suggestion is to find this in the VCR and look over the capacitors very carefully for leaking (not bulging). Look also for surface mount ones - and replace.

If there is nothing visibly amiss then you will need an oscilloscope and service manual and find where the problem is. Could be that the colour signal is being switched off by a transistor being falsely switched etc. The signal almost looks too good for failing capacitors as when they go you usually get loads of false colour and brown/blue etc.

glazuna 05-15-2017 04:25 AM

Been playing a tape for 1 hour now, no difference on the color aspect.. It could be me but it seems like the picture got brighter, again I'm not too sure. It could be just the same as it was...

Will definitely check the chroma board when I have some spare time.
But wasn't the RTV-950 exact same device as the FS200? So it should have boards covered with surface mount caps right?

It is strange though that I would have no color, but still a good sound, good front display lighting (well some parts of the display are dimmer than others yeah, but overall pretty good).

The device seems to have been made in 1999, as the last number is 9, and as it seems it was used very little. It had nearly no dust inside, buttons work nearly like new, markings are still like new, not rubbed away, screen is not scratched at all, remote is in the same condition. Only the top cover is quite badly scratched, but this is normal as most people had some other stuff on top of their VCRs..

It does seem like something had taken my colors away :hmm:

Quasipal 05-15-2017 05:00 AM

Quote:

Originally Posted by glazuna (Post 49370)
Been playing a tape for 1 hour now, no difference on the color aspect.. It could be me but it seems like the picture got brighter, again I'm not too sure. It could be just the same as it was...

Will definitely check the chroma board when I have some spare time.
But wasn't the RTV-950 exact same device as the FS200? So it should have boards covered with surface mount caps right?

It is strange though that I would have no color, but still a good sound, good front display lighting (well some parts of the display are dimmer than others yeah, but overall pretty good).

The device seems to have been made in 1999, as the last number is 9, and as it seems it was used very little. It had nearly no dust inside, buttons work nearly like new, markings are still like new, not rubbed away, screen is not scratched at all, remote is in the same condition. Only the top cover is quite badly scratched, but this is normal as most people had some other stuff on top of their VCRs..

It does seem like something had taken my colors away :hmm:

Hi, second character is year after the letter (which represents the month).

We are at a point where just age is killing off some components now - especially capacitors.
You say that RTV-950 is exactly same device as the FS200 but there may still be subtle differences such as where the units are assembled, quality of components - you say about buttons rubbing away from use, but FS200 buttons never lose their graphics - just get shiny from pressing. Just a thought.
Front displays only dim on these models when the display wears out, not from capacitors - unlike the USA models. Some parts of the display being dimmer means that it has been left powered up which also means that the PSU will need new secondary capacitors. As it happens once these begin to fail, one symptom is loss of colour...

glazuna 05-15-2017 05:03 AM

So you're saying it might be the PSU that is causing the loss of color? Would be worth checking it out before the other boards?

Quasipal 05-15-2017 05:10 AM

Quote:

Originally Posted by glazuna (Post 49372)
So you're saying it might be the PSU that is causing the loss of color? Would be worth checking it out before the other boards?

Yes, noise (hash) on DC output confusing the circuits on other boards. You need clean DC.

glazuna 05-15-2017 05:21 AM

Thank you, this guy had taken out the PSU form AG1970 which visually is the same device for NTSC
https://www.youtube.com/watch?v=bYzVgr_B3l4
Not sure what functions it is missing from the 1980, but from what I could see, it does not have surface mount caps inside, so all I can do is check the electrolytic caps for bulging or leaking I guess..

Quasipal 05-15-2017 05:41 AM

Quote:

Originally Posted by glazuna (Post 49374)
Thank you, this guy had taken out the PSU form AG1970 which visually is the same device for NTSC
https://www.youtube.com/watch?v=bYzVgr_B3l4
Not sure what functions it is missing from the 1980, but from what I could see, it does not have surface mount caps inside, so all I can do is check the electrolytic caps for bulging or leaking I guess..

Honestly, just replace them all with 105 rated low ESR Panasonic capacitors. They can fail without bulging or leaking - just wear out and dry up. If you have an ESR meter you can use that, but I just replace them all apart from the main reservoir cap.

glazuna 05-15-2017 05:44 AM

Quote:

Originally Posted by Quasipal (Post 49375)
Honestly, just replace them all with 105 rated low ESR Panasonic capacitors. They can fail without bulging or leaking - just wear out and dry up. If you have an ESR meter you can use that, but I just replace them all apart from the main reservoir cap.


Alright, very little amount of caps inside, compared to the other boards so I guess this is the best first step. Unfortunately no ESR meter at the disposal..

Thanks again, will report back once I actually start working on it. Might be some time, a month 'till then.

Quasipal 05-15-2017 05:50 AM

Quote:

Originally Posted by glazuna (Post 49376)
Alright, very little amount of caps inside, compared to the other boards so I guess this is the best first step. Unfortunately no ESR meter at the disposal..

Thanks again, will report back once I actually start working on it. Might be some time, a month 'till then.

With this range of VCR's so many faults are caused by these capacitors that it is worth replacing them as a precaution as soon as possible. Gives you a good place to start anyway.

I don't think USA AG1970 and AG1980 are as well built as the European models. We don't get all the loading problems they have or the dimming display.

glazuna 05-15-2017 11:20 AM

1 Attachment(s)
Wow you were actually right. I've taken out my PSU and while at it, it was necessary to lift up the whole chunk of boards just to get the power supply out with the cables still attached. After disconnecting it I could see that none of the circuits carried the infamous surface mount caps.. So I guess these recorders shouldn't be causing us much trouble after all huh, at least not any more than JVC 7000 and 9000 line right?

The power supply is exactly, I mean literally the same as in the FS200 on the attached picture


I haven't decided yet if I should leave it at any local tv shop to have them replace it or should I tackle it myself. But for the total of less than 30 caps it might be silly to give someone 50+ € if I can do it alone. Had soldered circuits before, though I also have dislocated some of the connection pads before.
I'm hesistant to drop more for the service of the psu than what I paid for the whole unit you know :P
Since this is no double sided board I guess if I do burn down the "trace pad" or whatever it is called, I can still link it with a piece of wire right? That wouldn't be possible on the other multi layer boards in the vcr if I'm correct.

Quasipal 05-15-2017 12:40 PM

I can offer to rebuild your PSU for 25 Euros including capacitors if that would help you.

glazuna 05-15-2017 01:46 PM

It would help, it depends how much the shipping would cost ;). Where are you from?

Quasipal 05-15-2017 02:22 PM

Quote:

Originally Posted by glazuna (Post 49386)
It would help, it depends how much the shipping would cost ;). Where are you from?

I'm in the UK.

glazuna 05-15-2017 04:02 PM

Ok drop me your home address in pm and I will ship the PSU tomorrow. This includes the replacement of the tantal and other type of caps in psu aswell?

Shipping it in a white USPS box registered box, so you will know instantly what it is when it arrives.

Quasipal 05-15-2017 06:00 PM

Quote:

Originally Posted by glazuna (Post 49389)
Ok drop me your home address in pm and I will ship the PSU tomorrow. This includes the replacement of the tantal and other type of caps in psu aswell?

Shipping it in a white USPS box registered box, so you will know instantly what it is when it arrives.

Hi, will do. No, just all secondary electrolytic. Never had any of the others go bad so leave alone as they are good quality ones and they don't go faulty like the electrolytic ones. I check the main smoother but usually never need to replace.


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