Cobra 29 LTD Classic High VCO voltage. Will not adjust.

[Low_Boy]

Replaced the junk YD brand 7310s with a Toshiba set the VCO voltage to 1.25 V and the radio fired up. So now Nomad you can say you heard of a mixer going bad on a Cobra 29. I was able to get the same peak on Pin 22 of IC1 and Pin 4 on the mixer. and I believe 10.240 MHz on receive on pin 22 of IC1.

How did you suspect IC2. And how should I have went further in trying to find this problem. I usually only try to ask after I hit a road block.

 

[Dmans]

Low_Boy,
Nomad has talents. Backed by years of experience. Wish I had a little of both!
Glad you got it going. Nothing better to rescue an “Orphan”.

73
David

 

[Low_Boy]

Low_Boy,
Nomad has talents. Backed by years of experience. Wish I had a little of both!
Glad you got it going. Nothing better to rescue an “Orphan”.

73
David

He sure does know his stuff.

 

[nomadradio]

How did you suspect IC2.

Goesinter, goesouter.

You had input to IC2, but no output. Helps to have a picture of what's inside the chip. The TA7310 has been around for 46 or more years. Used in lots of radios. Used it in the PLL synthesizer we used to build for the Browning Mark 4. Plenty of time to get familiar with it.

Enough decades in a row, and some things just sink in.

73

 

[Low_Boy]

Thanks