Yamaha CR 1020 no sound

ryanward84

Well-Known Member
I picked up a CR 1020 today and so far it powers up but no relay click. I am not very handy but I want to learn to bring this a receiver back to life. Funny enough I have another CR 1020 that is my main amp and operates as it should, so that may provide some insight in the repairing of this new to me unit.

What should my first steps be to troubleshoot the issues here?
 
They are known for issues in the power supply.
Resistors over cook and unsolder themselves.

Have you checked the amp adjustments?
Are you capable?
 
They are known for issues in the power supply.
Resistors over cook and unsolder themselves.

Have you checked the amp adjustments?
Are you capable?

I have not checked and will need to buy a multi meter. Like I said, willing to learn from AK, other online resources etc.
 
I will plan to get a multi meter and also to clean up the dust and grime and then go from there. Then checking the amp adjustment would be the next step? What would I determine by doing this?
 
First step would be to download the service manual, normally available from hifiengine, you will need to register, part of the protection against robots.
It's a safe site, then refer to the adjustments chapter. Do not touch the adjusters for the tuner unless asked to by another AKer. Appears the CR1020
does not have an adjuster for dc offset, which may be related to your problem. You should check the idle current as part of general house keeping.

No relay click typically means failure in the protection circuit (component, bad connection...) or excessive dc voltage is present on the speaker line
and the protection circuit has released the relay so as to protect the speakers. Need to determine which.

Remove woodwork, locate the relay (on power supply board underneath???)
Near the realy are 2 pins LI(Left In), RI(Right In).
Need to measure the dc voltage at LI, black multimeter probe connected to chassis or phono ground or black speaker post.
Should be less than 100mV, however it could be 1->50-??Vdc if faulty
Repeat for RI
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I will plan to get a multi meter and also to clean up the dust and grime and then go from there. Then checking the amp adjustment would be the next step? What would I determine by doing this?

If you intend to fix it, you will need a decent soldering station, desoldering tools and skill to use them.

It has been too long since I repaired a 1020 so I’ll let others guide you.

The one I did had the bad solder joints in the power supply caused by the over stressed resistors.
 
If you intend to fix it, you will need a decent soldering station, desoldering tools and skill to use them.

It has been too long since I repaired a 1020 so I’ll let others guide you.

The one I did had the bad solder joints in the power supply caused by the over stressed resistors.

Thanks for the advice. I have a good friend who has soldering tools and will be helping me out. I'll post again once I get going on the process. Thanks
 
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