"Pete KE9OA" wrote in message
...
Another thing I discovered.....................somebody had replaced the
blown 1st mixer with some sort of ECG substitute. As a result, the gain
was about 20dB lower than expected. I popped in the correct chip (SL6440C)
and the receiver is working quite well now. Sensitivity is very similar to
the HF-150, as is system gain. Lowe came out with a winner with this one.
If I get enough of these broken receivers, I may become a Lowe expert in
another 100 years.
Anyway, if anybody has some sort of problem with their receiver, feel free
to shout me down, using my e-mail address.
Pete
"Pete KE9OA" wrote in message
...
I picked up yet another "perfectly working" Lowe receiver. This one would
howl for the first 5 minutes of operation, the FM detector didn't work for
this time because of low I.F. injections level, and system gain would be
low during this time.
I traced the problem to a 100uF lytic cap near the audio amp. After the
unit warmed up, I hit several components with freeze spray. After I found
this problem component, I removed it completely and the problem became
much worse. When I tacked a cap into the circuit to test my theory, the
receiver started working properly. The cap must have been leaky, because
when I tried to parellel another cap across this one, no change was
noted.
This receiver uses the same audio amp as the HF150, so if you have a
receiver that howls even with an external speaker, this could be the
problem.
Between myself and some other friends, this is the 6th unit I have run
into that needs at least some kind of repair. It would seem that folks
get scared when these receivers start to malfunction, and "jump ship", so
to speak.
Pete
Hi Pete
I wish I knew more about diagnosing and fixing radios myself. All I've done
is replace some pots and minor mods and installation of items. I'm handy
though as I build computers.Thanks for the offer.
I'm looking for a 225 for my collection so I'm on the lookout for them. I
almost bought one from the U.K. but it didn't look that hot in the picture
posted.
Good going fixing that 225 up. There's nothing better then taking a
perfectly workable radio and restoring it to it's former glory.
Lucky
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