Technics SU-V9 No Relay switching / No sound


Kindly help to resolve my technics SU-V9 Calss A Amplifier..  Class A AmP lamp was blown and after replacing also no relay switching.. protection circuit seems not working. 
jibuvs
Now you’ve got a real problem. (actual circuit problem)

check the voltage in the relay input pins with a multi meter. There should be no voltage. If there is a voltage then there is a problem with the amplifier circuit.


If you’ve done that already and there is no voltage there, then, well..now you are getting into real and actual problem solving of a complex set of circuits.... and that is just not going to work out very well on a forum, in a few posts.

Additionally, due to the age of the unit and the parts that Panasonic was issuing at the time, a notable amount of some of the smaller signal capacitors probably need replacement. Those capacitors are 38-39 years old as of this year.

FYI, it is identical to the su-v909, where the 909 is brown faced and has international voltage switching.