Mark Rehorst wrote:

Thanks for all the input! I pulled the filter off the PCB so I could
bypass it with a cap and then realized the first IF transistor gets
biased via the transformer inside the filter can. I put it back on
the board and the radio came back to life! It was a bad solder joint
the whole time! I sure wish they had cleaned the flux off the boards
when they built these radios. I might have been able to spot the
problem without all this fuss...

Now where did I put that can of flux remover?????

MR

Its also possible that you have a bad solder joint or broken wire
inside the part, and the removal and resoldering has made a temporary
connection inside the can. I have seen it a few times on bad IF
transformers and other parts. Just keep it in the back of your mind, in
case it quits working again.
--


Michael A. Terrell
Central Florida

Also check to be sure there are no cracked cores in the interstage
transformers. Those are hard to find sometimes. If all stages tune
correctly then they might be ok. When the cores crack they detune the
coil they are in.

Mark Rehorst wrote:

I am trying to fix my recently and suddenly deaf SX-190 receiver and
can't seem to find the problem. I have a DMM, an uncalibrated sig
gen, and a 100 MHz scope available. Of course, I have schematics,
etc.

MR

Also check to be sure there are no cracked cores in the interstage
transformers. Those are hard to find sometimes. If all stages tune
correctly then they might be ok. When the cores crack they detune the
coil they are in.

Mark Rehorst wrote:

I am trying to fix my recently and suddenly deaf SX-190 receiver and
can't seem to find the problem. I have a DMM, an uncalibrated sig
gen, and a 100 MHz scope available. Of course, I have schematics,
etc.

MR

On Fri, 31 Oct 2003 11:22:03 -0500, jim breeeyar
wrote:

Also check to be sure there are no cracked cores in the interstage
transformers. Those are hard to find sometimes. If all stages tune
correctly then they might be ok. When the cores crack they detune the
coil they are in.

I'll keep it in mind for future reference. My radio has been fixed-
it turned out the second mechanical filter had a bad solder joint.

Thanks,

MR

On Fri, 31 Oct 2003 11:22:03 -0500, jim breeeyar
wrote:

Also check to be sure there are no cracked cores in the interstage
transformers. Those are hard to find sometimes. If all stages tune
correctly then they might be ok. When the cores crack they detune the
coil they are in.

I'll keep it in mind for future reference. My radio has been fixed-
it turned out the second mechanical filter had a bad solder joint.

Thanks,

MR