Ka-7100 problem

[Soundslave]

i have a ka-7100 that I've recapped the P/S-Amp board, new relay, Q34, d27. Could not see what was causing the loud pop at turn on. After replacing the relay I can see that at cold turn on the relay makes contact then releases for a second then makes contact and holds. If I turn it off then back on it will hold without any bounce. Also should there be a delay at turn on before the relay engages?

 

[petehall347]

there should be a few seconds delay
change ce39 ce40 ce41

 

[Soundslave]

Did so when I recapped the P/S Amp board

 

[petehall347]

are the voltages all correct as stated on the schematic for protect circuit ? if so i suggest upping the uf of ce40 to 220uf and see if it then gets a delay at turn on .. it could be that ce40 has a bad connection so maybe check that first .

 

[gort69]

Also, have you measured and adjusted center voltage to 0? (p. 16 of s/m) http://www.vintageshifi.com/repertoire-pdf/Kenwood-5.php

 

[Soundslave]

Reflowed ce40 joint, no change. Set offset and bias Before and after recap.Will look for a replacement cap (220uf).

 

[Soundslave]

After checking voltages in the protection circuit I found that De15 was bad. Now the relay works as it should. On to recapping the control unit and preamp boards. Any suggestions on what else should be done to one of these, maybe some film caps? Reseat the outputs?