On Tue, 15 Feb 2005 16:11:21 GMT, "U Know Who" wrote:


This is a common problem. In many cases, if you remove the cover the
problem will go away. The final stage is going into oscillation and
the "carrier" you see is that oscillation. Usually (and unfortunately)
the oscillation falls in the 29 Mhz area.

Sometimes this problem is caused by added mods that people add to try
to squeeze a few more watts out of it. There are added capacitors on
the bottom side of the board that can cause this. If you see an extra
cap (or two in parallel) on the underside of the board connected to
the final, remove it and that should cure your problem.


You nailed it on the head. Cover off, oscillation gone. Now I have to
isolate
it.

Vinnie S.

Rebias the output.



Damn !!!!

I was hoping I didn't have to use a DMM. The DMM I have doesn't have current
measurements. Well, it's not mine. Mine was actually (Fluke 77). stolen. I have
a scope, and freq counter. But to way to adjust bias current. I will ne to get a
hold of another DMM.

Vinnie S.

"Vinnie S." wrote in message
...
On Tue, 15 Feb 2005 16:11:21 GMT, "U Know Who" wrote:


This is a common problem. In many cases, if you remove the cover the
problem will go away. The final stage is going into oscillation and
the "carrier" you see is that oscillation. Usually (and unfortunately)
the oscillation falls in the 29 Mhz area.

Sometimes this problem is caused by added mods that people add to try
to squeeze a few more watts out of it. There are added capacitors on
the bottom side of the board that can cause this. If you see an extra
cap (or two in parallel) on the underside of the board connected to
the final, remove it and that should cure your problem.


You nailed it on the head. Cover off, oscillation gone. Now I have to
isolate
it.

Vinnie S.

Rebias the output.



Damn !!!!

I was hoping I didn't have to use a DMM. The DMM I have doesn't have
current
measurements. Well, it's not mine. Mine was actually (Fluke 77). stolen. I
have
a scope, and freq counter. But to way to adjust bias current. I will ne to
get a
hold of another DMM.

Vinnie S.

I have seen the same situation you are describing in a 2510. The guy never
used it SSB, and it worked fine on AM. He later sold it to someone who did
use SSB. Turned out the "Tech" who did the frequency mod on the radio was
also asked to tune it for maximum. He did so, but never noticed it went into
oscillation on SSB. After resetting the bias to the correct level, the
problem went away.

Hope this helps.

On Tue, 15 Feb 2005 16:22:55 GMT, "U Know Who" wrote:


You nailed it on the head. Cover off, oscillation gone. Now I have to
isolate
it.

Vinnie S.

Rebias the output.



Damn !!!!

I was hoping I didn't have to use a DMM. The DMM I have doesn't have
current
measurements. Well, it's not mine. Mine was actually (Fluke 77). stolen. I
have
a scope, and freq counter. But to way to adjust bias current. I will ne to
get a
hold of another DMM.

Vinnie S.

I have seen the same situation you are describing in a 2510. The guy never
used it SSB, and it worked fine on AM. He later sold it to someone who did
use SSB. Turned out the "Tech" who did the frequency mod on the radio was
also asked to tune it for maximum. He did so, but never noticed it went into
oscillation on SSB. After resetting the bias to the correct level, the
problem went away.

Hope this helps.



Does help. Thanks !!!!!!

Vinnie S.