[dudu_mec]

jacek1313 wrote:

Hello, have you tried giving a “fingertip” signal to R93 and R91? Maybe you have the TR42, TR64, TR60-64 transistors driven, i.e. the MUTE signal from IC1?

That’s actually a good point. It can also be the mute circuit.

What’s a fingertip signal?

applying a signal to one or the other resistor, thus bypassing the TDA?  That way if I have sound then it’s not the mute circuit. If I continue without sound it can be the mute circuit or the ICs.

but does the mute also apply to the masterlink output? Currently I also don’t have output there

cheers

[dudu_mec]

Hi Matador,

That’s unfortunate to hear. So I might have a glorified paperweight or a potential parts donor.

Some questions are still brewing in my mind:

• Is the small clamper more prone to frying ICs than the large clamper? and why? Thought the differences circuitry were not that big. At least on the preamp board which seems to be the same in Ouverture/3000 and 3200
• From looking into the service manual I’m pointing at IC1, IC2 and IC4 in the preamp board. Apart from IC4 which I could not find new, only NOS replacements, the others are still available.
  • IC1 – CD4052
  • IC2 – CD4094
  • IC4 – TDA7318D
• You talk about custom made ICs. How is that possible?

 

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