Hi,
a HAM friend got a problem with his IC2KL. The lamp "protector"
signalize something is wrong with amplifier. He worked with it and ALC
line was not conected (it should be because protections are mostly
conected to ALC line). Protector lamp can't be reset when the amp is
turned ON. I have checked the main unit, it seems nothing is wrong
with it (I checked most of transistors and diodes exept TX part Q4,
Q5, Q6 and Q7). IC2a in b (NJM 4558) in main unit puts out +19v on pin
1 and 7 I'm not shure athat is normal without drive and RF out. I
think the output at pin 1 should be near 0V without RF drive and RF
out. I noticed the modified HV DC power suplay gives 57V DC and I
think is way to high (it should be 40V DC). Because of realy poor
modification the HV DC cant be adjusted. Because of abnormaly high HV
DC the DC-DC konverter gives out + and - 20V (it should be + and -
13,8V). It might be the protection circuit reacted because of high DC
voltage as the NJM 4558 maximum voltage is + and - 15V. It also seems
the Q4 is always ON (at the linear amp swith off it sholud have 13V at
the base, but it don't have).
Please anybody know where to get service manual for this amp or how to
check which of protection circuit reacted?
Regards, Branko, S52V
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