got a yamaha cr-820

se7en8n9ne

Active Member
so someday i'd like to get a cr-1020 but right now they are out of my price range. so i broke down and got an 820 that "needs cleaning" and "tlc".
What i was wondering is if anyone has any suggestions about what to look for problem wise and if there are any cleaning how-to's that i have missed.
I have deox-it and experience cleaning a kenwood kr-5010, yamaha cr-640 and a couple others.
 
Congrats on scoring the 820. I have a 620 that only needed the bulbs replaced. Are you getting any static in the controls? Some of the pots are hard to reach on these. Luckily I didn't have to deox-it mine much, as all the controls were quiet and she worked just fine. I sprayed the pots and switches anyway when I went in to replace the bulbs. And the interior is very clean for an older piece of gear.

Give a little more detail of what's wrong with the unit and I'm sure you will find the help you need. I am but a rookie!
 
So quick question now that I got around to taking it apart I was wondering if you take both front plates off to clean pots and stuff?
 
Looking for the same answer. I've seen it discussed here before and I'm trying to search for the answer. Have not opened mine up yet.
 
no sound from my cr-820

so the other day i used the headphones on my stereo which was fine but now i can't get it to play through the speakers.
any suggestions, thanks guys
 
so the other day i used the headphones on my stereo which was fine but now i can't get it to play through the speakers.
any suggestions, thanks guys

Speaker select switch still dirty. Or broken wire or soldered connection, Perhaps ? Did you try both speaker A and B ?
 
haven't tried b speakers yet i'll have to do that when i have time but i doubt that's it cause now the headphones don't work either.
 
haven't tried b speakers yet i'll have to do that when i have time but i doubt that's it cause now the headphones don't work either.

so the other day i used the headphones on my stereo which was fine but now i can't get it to play through the speakers.
any suggestions, thanks guys

So what is the story ? First you say it works, then you say it doesn't.
If the headphones don't work.. Does the protect relay "click" ?
 
Last edited:
i tried the b speakers and still no dice.
i'm afraid it's a power supply issue or something i can't fix. there's no sound not even static but the lights come on. any ideas
 
Sorry avionic to ignore you. No there is no click, and it was the next day that nothing worked. Sorry about the confusion
 
No click? It's dead then.

Did it ever work? Or did it die on you?

Do not worry however. It's very much fixable. You might not be able to, yet, but someone can. Unlike the CR-840, for example.
 
BTW... There are a few common failure points on these and the 620, but poetically one found it to usually be a pair of bad outputs. Easy to check, and easy fix if they are bad.

Sent from my Nexus 4 using Tapatalk
 
I guess it's time to invest in a multi meter. Do you want me to pm you when I get one or no?
As far as the other question...Yes it worked GREAT for about a month until I used the headphone Jack then it wouldn't work on either speaker or headphone
 
got a meter to...

now i have a meter i can check the cr 820. i am looking for suggestions of what to check and how. thanks for your patience
 
http://www.hifiengine.com/library/yamaha/cr-820.shtml

OK.. First we need to check for any DC voltage at the output of each amplifier. You need to locate L701 and 702 ( coils of thick copper wire, very close to the speaker select buttons on the main circuit board)

With your meter in the DC volts mode. Clip the black test lead to the metal chassis ie. ground .. The with the red test lead scratch through the enamel coating on each coil and record the voltage on the coils and post the voltages here. Ideally there should be zero volts, realistically a few millivolts which is no problem. If you have 500mv or greater -Houston ,We have a problem.

Note of caution..to prevent accidentally shorting something out with your test probes - wrap some electrical tape or heatshrink tubing over the end of the probe tip , leaving the very point exposed. :thmbsp:
 
Last edited:
Not enough voltage on the output to trigger the protect circuit.
Next we need to check the power supply circuit that supplies voltage and current to the protect circuit.
 
Look for approx. 11- 12 volts at the emitter of TR805.


Note:
Most likely you have a dried up small electrolytic cap in the PS/protect circuit.

Look over small capacitors C801 - C804 in the protect circuit. Look for bulging or label shrinkage or even signs of previous dried up ,crusty leakage around there bases. Yellow to brownish in color with greenish blue oxidation on the components leads.
 
Last edited:
Back
Top Bottom