Cobra 148 gtl Philippines squeals on AM only
 

Any ideas. Thanks

Cobra 148 gtl Philippines squeals on AM only
 

Gumpit wrote:
Any ideas. Thanks


Talkback? High SWR? Bad coax shield ground?

I can't see your setup from here.

Cobra 148 gtl Philippines squeals on AM only
 

No talkback,Perfect swr,good ground.....Happened after roger beep was
installed and removed. Randy

Cobra 148 gtl Philippines squeals on AM only
 

Gumpit wrote:
No talkback,Perfect swr,good ground


Did you tune your antenna from resonance to get a 50 ohm load?
I'd rather have a 1.5 and resonant system then a 1:1 non-resonant
system. Notice how little voice power it takes to get the shower
to sing back to you when you hit the right note (frequency). The same
thing happens for receive and will more then make up for the 3% loss.

A dummy load has perfect SWR, too.


.....Happened after roger beep was
installed and removed. Randy


Check for a loose, broken or missing bypass disk capacitor, probably
near the mike plug.

If you still can't find it, join the cbtricks Yahoo group and ask there.
doggie chased the rest of the helpful folks off with his "winning" ways.

Cobra 148 gtl Philippines squeals on AM only
 

On 26 Mar 2006 11:36:25 -0800, "Gumpit" wrote:

Any ideas. Thanks

See if any of the circuit board ground to chassis ground capacitors
have come loose.

Cobra 148 gtl Philippines squeals on AM only
 

"Gumpit" wrote in
ups.com:

Any ideas. Thanks


Yes, I've heard of this happening before. Your radio is dry and needs to
be lubricated to get the squeal out.

Get some WD-40 (Comes in a spray can) Take the covers off the CB so you
can see the componant side of the PC board. Now completely spray down
everything until the the can is almost empty and then use the last little
bit and spray inside the microphone. Let it soak about five minutes.
Next it's time to remove the excess lubricant. Take the radio out to the
middle of your concrete driveway, and throw a lit match in it. This will
burn away the excess lub. To clean the smoke smell inside, put the CB in
your dishwasher and run on Pots & Pans Cycle.

HTH, 73

SC

Cobra 148 gtl Philippines squeals on AM only
 

Yes a dummy load was used.....O.k. I switched the mic board with one
from a 2000gtl..Now the squeal is gone but it throws a carrier that
sounds real hashy on sideband with little or no audio...Do you think it
is the audio chip or a capacitor that may be bad? And which one? Randy
Slow Code wrote:
"Gumpit" wrote in
ups.com:

Any ideas. Thanks


Yes, I've heard of this happening before. Your radio is dry and needs to
be lubricated to get the squeal out.

Get some WD-40 (Comes in a spray can) Take the covers off the CB so you
can see the componant side of the PC board. Now completely spray down
everything until the the can is almost empty and then use the last little
bit and spray inside the microphone. Let it soak about five minutes.
Next it's time to remove the excess lubricant. Take the radio out to the
middle of your concrete driveway, and throw a lit match in it. This will
burn away the excess lub. To clean the smoke smell inside, put the CB in
your dishwasher and run on Pots & Pans Cycle.

HTH, 73

SC

Cobra 148 gtl Philippines squeals on AM only
 

What a f*cking troll you are.

Go pound some brass, slowly!