CED VideoDisc and Player Discussion

[Caroline]

I am a proud owner of a ced player for a week now
( the RCA SKT 090 ), but the volume level is incredibly low.
I have read in the faq page, that I have to open the CED player to raise the volume ( very strange ), but I cant find anything in there.
Here in the Netherlands, the CED system is totally unknown.

[RT9342]

Well, I can take a look at my SJT-090 board to find the exact location of the control (and hope that it's in the same place as an SKT-090 board), but there if you locate the board, there are several adjustments, and one of them should be either labled AUDIO LEVEL or L+R LEVEL. I can try to confirm this in the next couple of days, but if you find such a control in the mean time, take note of the current setting, then play around with it a little. If you still can't get it loud enough, then I would suspect a problem in the circuitry, possibly in the modulator. I can find out which test point carries the audio signal, so you can check it on a stereo or something to see if it's strong before entering the modulator.

[Caroline]

that you have to open the CED only to raise the volume ? I will try this Monday, when I am working in the VCR repairservice. Usually we repair old laserdisc and videosystems. The CED is totally different and strange for us Europeans.

[Caroline]

The stylus only has around 50 working hours, so it should be the volume
level, but I cant find the button, there are no labelings on my CED board, only short code numbers, like R2-D2, is a schematic circuit helpfull ?
The SKT-90 seems to be different from other CED Players, or ?

The picture is exvellent, but the volume level very thin, the noise very loud.

[RT9342]

Hmm...if only I had my schematic with me...I'll have to see exactly where the part is, but I'm thinking it's toward the back of the board. It's one of those little round, colored parts with a slit & hex-head on the top (some are yellow, some are red, some blue, I think the audio ones may be black). But the problem is almost definitely either one of those adjustments or a bad electronic part. If the stylus only has about 50 hours of play, then it should be in practiaclly new condition. Usually a worn stylus will show one or more of the following problems: constantly muddled & somewhat physchedelic picture, frequent skipping, and in severe cases, some static noise in the audio, but it shouldn't affect the volume, and if the picture is clear, then the stylus is certainly good. Right now, I'm out of town for the holidays, but when I get back, I'll try to find my schematics. I don't remember if you mentioned the model number in the previous posts or not, but if not, please let me know what model you have, so I know which schematic to refer to.

[Caroline]

I am studying electronics, and I never had found a video machine I couldnt repair, but this CED system is totally different.
You have to dissemble the whole player only to turn up the volume !?!
This is really VERY user-unfriendly !

[RT9342]

Hey, Caroline. Sorry for taking so long to reply. I went through my schematics, but I forgot that I only have complete schematics for older models, and my schematics for the later models only deal with the computer controls. But I went through my old parts and found the chassis from my SJT-090. Just to warn you though, the SKT-090 may be different from the SJT-090, even though they look the same. Also, I don't remember if you said your player is PAL or NTSC - there could be some differences if it's a PAL unit (I never actually looked inside an SKT model or a PAL version).

But here's what I found in my player: first of all, it turns out that you don't have to take the whole player apart, but you do have to remove the bottom, and the motor could make a lot of racket if you try to adjust the controls inside while the bottom is removed (as you suggested, RCA never really made these very easy to repair, and I really don't know why they went to such a flimsy chassis on the later models). You'll find a big circuit board down there, and if you pull it out, look on the right side (from the back, which would be the left side from the front), and right there on the back corner should be a little green knob (labeled L+R LEVEL) and a black knob (labeled VCO, or something like that). There's probably a 2-wire plug-in cable near by these knobs. I'd suggest attempting to adjust the green one (L+R LEVEL) and see if you can't get more volume. Some models also have a TV AUDIO LEVEL knob next to the RF modulator (the big silver box on the circuit board with the TV connectors), but I don't think the SKT-090 has that control.

If all else fails, you could try to adjust the black VCO knob, but be sure to note where it was set before you adjust it, and try to put it back exactly where it was if it does no good. This adjusts the tuning frequency (kind of like a radio tuner dial - and imagine trying to tune your radio just right to pick up a weak radio station - that's kind of what you're dealing with here).

If you have headphones or something to test for audio signals, you may want to check TP4001 (a metal stake sticking up, near the green L+R LEVEL knob) or TP3504 (a wire across the circuit board just in front of the big modulator that I mentioned). At least one of these points should have an audio signal present. If you still can't seem to get a decent volume, then you probably have something burned out (probably a part nearby the knobs mentioned). You might also try checking that 2-wire cable - make sure it's making a good connection, and not shorted or anything.