Sony TC135SD cassette recorder

Just rebelted my cassette recorder. What used to be an occasional thumping in the left channel is now there all of the time. It almost sounds a litt le like motoroboating, but maybe a higher frequency. If I push the stop bu tton and hold it down, it goes away temporarily. Sometimes there is a litt le bleed of that into the right channel; but always predominately left chan nel. Would this be a bad cap in the power supply only affecting one side? I do have a schematic diagram for this unit.

Reply to
harryhomer
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the left channel is now there all of the time. It almost sounds a little like motoroboating, but maybe a higher frequency. If I push the stop button and hold it down, it goes away temporarily. Sometimes there is a little bleed of that into the right channel; but always predominately left channel. Would this be a bad cap in the power supply only affecting one side? I do have a schematic diagram for this unit.

It is the record playback switch. If you can find one, replace it. If not, Deoxit 5 squirted into the switch might repair it. This doesn't work 100% of the time. It was such a common problem back in the day we used to stock piles of replacement switches for all brands. Chuck

Reply to
Chuck

the left channel is now there all of the time. It almost sounds a little like motoroboating, but maybe a higher frequency. If I push the stop button and hold it down, it goes away temporarily. Sometimes there is a little bleed of that into the right channel; but always predominately left channel. Would this be a bad cap in the power supply only affecting one side? I do have a schematic diagram for this unit.

Check the shielded wire from the heads, make sure the shields are still connected.

Also, make sure the PC boards are firmly screwed down to the chassis, the post many times have ground pads on them. You need to make sure all bypass caps are still connected to ground..

Jamie

Reply to
Jamie

thumping in the left channel is now there all of the time. It almost sounds a little like motoroboating, but maybe a higher frequency. If I push the stop button and hold it down, it goes away temporarily. Sometimes there is a little bleed of that into the right channel; but always predominately left channel. Would this be a bad cap in the power supply only affecting one side? I do have a schematic diagram for this unit.

Agreed on that As its such a work up to desolder these to disassemble and clean or even replace. One last resort is to melt the solder points , in turn and with a needle inserted in the hole , put a set on the common pins of each switch , so a different area of the contacts is used. Sometimes its possible to remove the covers of these switches by bending or cutting the tangs under the paxolin and removing , then cleaning the contacts individually , and replacing the cover as best as possible. Problem tends to be either compacted grease or build up of copper sulphide insulating corossion

Reply to
N_Cook

ng in the left channel is now there all of the time. It almost sounds a li ttle like motoroboating, but maybe a higher frequency. If I push the stop button and hold it down, it goes away temporarily. Sometimes there is a li ttle bleed of that into the right channel; but always predominately left ch annel. Would this be a bad cap in the power supply only affecting one side ? I do have a schematic diagram for this unit.

Thanks all. I had long suspected it was one of the switches, but wasn't su re how to proceed; will investigate the approaches presented and let you kn ow how I make out. Thanks again!

Reply to
harryhomer

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