Yamaha CR-1020 Only one channel working!

lprecords

New Member
Hello All,
Long-time 'reader' but first time poster, and I hope someone can help.

I have been happily enjoying my CA-810 amp for the past year or so, with no issue. However, I recently picked-up a cosmetically beautiful CR-1020, that, unfortunately, seems to have an issue...

Using speakers, output from Right channel is clean, clear and strong. There is no output from Left speaker. This is reflected in the meters, where I see the right watt meter moving, but do not see anything from the left meter. If I move speaker selection to 'off' and crank the volume, I see the right meter almost pegged, while I see just a bit of movement in the left meter. Interestingly, when using headphones, I hear volume on both sides (with meters moving about the same distance)...BUT...at a very low db, AND if I move the balance to left, I hear nothing.

I've Deox'ed what I could, and no obvious switch problems...Dolby is "off", Coupler is "on", etc.

Any thoughts at all would be greatly appreciated! She is a real beauty, and I am really looking forward to hearing her how she should sound!

Thanks for any advice...
 
Welcome aboard! Did you deOxit the coupler switch really well? I do believe those can cause a channel to drop if they get dirty enough.
Any idea if the service bulletin mods were done?
 
Thanks for the reply! The coupler switch is a bit tough to get at...below a board. I will try and give it another shot.
 
Hello lprecord !

Do you have measurment tools like oscilloscope ?

If yes take a look on the input signal coming to the "dead channel" and see what it looks like at the output of this "dead" channel

This way , you will have confirmation that your amp is working on both channels and your trouble may be come from the relay or from somewhere else between module and speaker :thmbsp:
 
FWIW, the power supply on those develop problems due to varistors drifting off spec and solder joints getting bad. It may need attention there.

I don't know off hand if there is a separate power supply line for the amps.

Are you up to checking the amps with a DMM? Pull the service manual and study it. http://www.hifi-manuals.com/Yamaha/page-12

Avionic should be along shortly and chime in. He knows them well.
 
Thanks for the advice folks...I've been very fortunate over the years in that my love of vintage audio has produced trouble-free units I've owned, that have matched my extremely limited capabilities under the hood! DeOx, changing bulbs/amps, replacing fuses...that stuff I'm good at; anything else, I'm in trouble!

No scope, but I think I have a multi-meter kicking around somewhere...anything I can check with that?
 
FWIW, the power supply on those develop problems due to varistors drifting off spec and solder joints getting bad. It may need attention there.

Varistors in the power supply..Where? Not in a 1020..:no:
 
Did you try and exercise the couple/decoupler switch on the rear panel? Better yet. Jumper the pre-out/main-in rca jacks with a spare RCA interconnect patch cord.


Need to determine if the problem is in the pre-amp or the power amp.
Jumper the pre-out/main-in rca jacks with a spare RCA interconnect patch cord.

I'm thinking you have a switching or pre-amp issue. If you have a separate power amp or preamp. You can decouple the 1020 and verify if either the power amp(s) are working or not.Or the preamp/switching is working or not.
 
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Varistors in the power supply..Where? Not in a 1020..:no:

Arrg, fusistors, not varistors. On the electrolytic cap C board. Sorry.
FR801, FR802 22ohm 150ma and FR803 10 ohm 22ma. I had the FR803 unsolder itself.

I don't think that is the issue here.
 
Arrg, fusistors, not varistors. On the electrolytic cap C board. Sorry.
FR801, FR802 22ohm 150ma and FR803 10 ohm 22ma. I had the FR803 unsolder itself.

I don't think that is the issue here.

I figured that's what you meant to say. Had to pull your chain a bit.:D
 
Hello, fairly new here and just picked up a CR-600 the other day. Looks perfectly mint-wood, etc. anyway, the left channel is not working. I only tried the FM on my Cornwall II's. I have NO experience. I do have a Kenwood KA-7100, should I hook that up to the Yamaha?? I use the cornwalls daily as my main speakers in my HT, so I know the speakers are fine. When I turn the balance knob, I get absolutely nothing. Any advice, or if anyone knows of a tech in Eastern Idaho-I know I live in the sticks-Kinda?
 
Hello, fairly new here and just picked up a CR-600 the other day. Looks perfectly mint-wood, etc. anyway, the left channel is not working. I only tried the FM on my Cornwall II's. I have NO experience. I do have a Kenwood KA-7100, should I hook that up to the Yamaha?? I use the cornwalls daily as my main speakers in my HT, so I know the speakers are fine. When I turn the balance knob, I get absolutely nothing. Any advice, or if anyone knows of a tech in Eastern Idaho-I know I live in the sticks-Kinda?

I think you should start a new thread and not complicate this one - hijacking it from the OP.
 
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