Sony TC-K620 3 head cassette has gone Sybil on me. Power button issues? IDK

[Ric Harris]

When it works it works when it doesn't the led's don't all light up just a scattering of pulses and the buttons don't respond. Could the power button be to blame?
Then theirs the squeal that won't quit till it's unplugged completely. Motor I'd be guessing there but any suggestions. I've heard others speak of these old Sony's as being notorious for one thing or another.
I'm hoping someone has been here and done that.
Oh if I have a camera ready it works great! LOL!

 

[hdrobien]

I had a TC-K620 with similar problem. Worked fine when cold then became unresponsive with display showing strange signs before turning off.

Turns out to be a defective ir remote sensor. Works like a charm since its replacing.

You can check pretty easily, look at the schematic and cut the jump wire at the right low corner of the main board, close to the wires that lead to the display/command board. It will disconnect the sensor and you can resolder a wire if necessary.

 

[Ric Harris]

I had a TC-K620 with similar problem. Worked fine when cold then became unresponsive with display showing strange signs before turning off.

Turns out to be a defective ir remote sensor. Works like a charm since its replacing.

You can check pretty easily, look at the schematic and cut the jump wire at the right low corner of the main board, close to the wires that lead to the display/command board. It will disconnect the sensor and you can resolder a wire if necessary.

Did your squeal as well or might it be a motor/belt issue.

 

[PE9ZZ]

Turns out to be a defective ir remote sensor.

Cut the wire, works like a charm. Spent many hours chasing this fault. Hate these intermettent faults...

This deck is a bitch to work on, took it apart and in the end it wasn't even necessary:

 

[jobrewer1983]

I had a TC-K620 with similar problem. Worked fine when cold then became unresponsive with display showing strange signs before turning off.

Turns out to be a defective ir remote sensor. Works like a charm since its replacing.


You can check pretty easily, look at the schematic and cut the jump wire at the right low corner of the main board, close to the wires that lead to the display/command board. It will disconnect the sensor and you can resolder a wire if necessary.

great info, I have a KA630es, doesn’t have any issues but if I run into this now I know

 

[hdrobien]

The TC-K630ES is a totally different deck, not sure that it can suffer from this issue.

 

[PE9ZZ]

Stupid thing is I've had this before (OK, different equipment) but still caught me unawares.

 

[Shawnnnn]

I had a TC-K620 with similar problem. Worked fine when cold then became unresponsive with display showing strange signs before turning off.

Turns out to be a defective ir remote sensor. Works like a charm since its replacing.

You can check pretty easily, look at the schematic and cut the jump wire at the right low corner of the main board, close to the wires that lead to the display/command board. It will disconnect the sensor and you can resolder a wire if necessary.

Can you be a little more specific on which wire to cut please hdrobien?

I downloaded the schematic and found the remote ic on it but can't figure out where the wire is.

Thanks!

 

[Peter1977]

Can you be a little more specific on which wire to cut please hdrobien?

I downloaded the schematic and found the remote ic on it but can't figure out where the wire is.

Thanks!

View attachment 2548474 View attachment 2548472

Sorry for my poor English. Check the wiring diagram and look for IC751 (SBX 1610-59). Disconnect leg 1 (B+) or replace the electrolytic capacitors in the sensor module (IC751).