Kenwood KR-5030 receiver problems

[flambart]

Hi, when I turn my KR-5030 on, the relay works (after some seconds, of course) ONLY if the source selector is in its PHONO position. In any other position (AUX, FM Mono, FM stereo and AM) the relay does not work
Again: during the first minutes, every change from the working phono position to any other source implies a de-activation of the relay, and the intervention of the protection. Coming back to Phono, the relay works again

When the receiver is warm, everything works, but if I turn the receiver off I have to restart it with the phono source selected, and only afterwards (even immediately, if it's warm) I can change the source

Which can be the reason of this strange behaviour ?

Thanks so much, Paolo

 

[sregor]

I'm almost afraid to respond - looked at the manual, and could find nothing remotely connecting the relay protection circuit to the selector switch. About the only thing which is switched besides the signal itself is the indicator lamps. Only guess is that power supply voltages are on the low side, and no phono lamp. Other idea would be something miswired, in which case anything goes. Good luck with it.

 

[jaycee]

A quick google shows this unit is from the 70s... in this case, it is almost certainly a symptom of dried up electrolytic capacitors, either in the protection circuit or signal coupling capacitors. You should replace all of them with new ones.

 

[birdbrain 62]

Kenwood 5030

I bought this unit new and within no time - a couple of months use- the on/off switch became finicky and the panel lights would flicker. You could hear the sound of a bad electical connection. I believe this model has a factory defective switch. Not helping the situation is the fact that you had to click through the phono setting just to here the radio as I recall.This should have had an independent on switch. Anyone care to comment?

 

[sregor]

It's 30 years old ... They had problems with the switches right away. The correct service action was to replace the AC switch module with a switch module that had two pairs of contacts, and then connect the two pairs in parallel. Many people clean the switch, but this (as you can attest to) doesn't last. There are many threads about this in audiokarma.org - the best current fix is to take it apart (not that hard to do) burnish the contacts, and adjust the metal so that there is good tension in the contact. If you could get a hold of a second switch, you could take the set of contacts out, and put it in the module with the first switch. Others have jumped the contacts, and put in separate switch. I would even consider attaching a relay, and controlling the relay with a switch. FWIW, performance-wise IMO this was an very good unit for the money.. As to the selector, when it was sold, very few components were hooked to the aux inputs, and the primary uses were either FM, Phono, or Tape.