Yamaha CR-240 troubleshooting

[JLantz]

Hi,

As mentioned in my initial thread, I have acquired a new piece of malfunctioning gear that I would like to fix, if possible.

Yamaha CR-240 "Natural Sound Stereo Receiver"

The symptoms:

-No sound from either headphone jack or speaker outputs
-No relay switching when turned on
-Lamps in tuner window blown

What I have done so far:

-Cleaned exterior and interior
-Removed the relay cover

When I make the relay's right side connection, I get a functional right channel both through headphones and the speaker output.

When I make the relay's left side connection, I get static/hum both through headphones and the speaker output. The music can faintly be heard when the volume is turned to max.

When I force the relay to trip and both connections are made, the static/hum from the left channel bleeds through to the right. I cannot eliminate the noise by turning the balance to the right.

Also FWIW, when I make the relay's left (bad) connection, the relay will eventually trip.

-I can hear a clicking (through headphones) when I tap on the lowest of the big capacitor pair shown in the picture.

-Checked all interior fuses with a multimeter; no opens

 

[ryuuoh]

Sounds like a blown module. I believe you can still get those STK modules. Also, I wouldn't keep doing the relay thing, you'll probably loose a speaker if there's a high amount of DC voltage at the speaker terminals.

 

[avionic]

One of these has " Crapped out " ..

 

[JLantz]

Lame.

After researching, it looks like repairing this would be more trouble that it is worth.

I'm in the Tacoma WA area; if any one wants this for parts, it's yours for what I've got in it; $11.

 

[cademan]

No, its not more trouble than its worth! Those STK modules are easy to replace. Just determine which one is the left channel module!

You may still be able to use the right channel for mono or a center channel depending on your needs or wants.

If you remove the faulty left channel module, I'm pretty sure the relay will click in on its own.