TRC-422A alignment anyone?

[Deleted]

This TRC-422A, has no financial value, and all sentimental value. It is my first ever CB. I tried to put it in to use, and the receiver is just too noisy. Lots of white noise. I can hear people with strong signals, but people S3 or lower are a lost cause.

I do not remember this radio being this noisy. Anyway, it is from 1983. Long after the SAMS books, and too far back for Radio Shack to have a service manual. I have emailed vaious CB shops in hope that they have a procedure. No deal. This is an AM only rig, and would be a breeze to align.

Can anyone help. Could the caps have gone bad in this radio?

[Sandbagger]

Jul 13, 2010 18:39:53 GMT -5 @vinnies said:

This TRC-422A, has no financial value, and all sentimental value. It is my first ever CB. I tried to put it in to use, and the receiver is just too noisy. Lots of white noise. I can hear people with strong signals, but people S3 or lower are a lost cause.

I do not remember this radio being this noisy. Anyway, it is from 1983. Long after the SAMS books, and too far back for Radio Shack to have a service manual. I have emailed vaious CB shops in hope that they have a procedure. No deal. This is an AM only rig, and would be a breeze to align.

Can anyone help. Could the caps have gone bad in this radio?

All I can say is "could be". That radio is old enough to start having "10 volt blues" type issues with small electrolytic caps. But before you start shot-gunning all the caps in that radio, you can do a few checks. Does the radio have the excessive "white noise" when it's hooked up to the signal generator, or only on an antenna? Does the noise blanker circuit affect it?

Try giving it a receiver alignment first, but align for best signal/noise and not s-meter deflection. Some radios will have more noise if they are aligned for greatest meter deflection, over the S/N method.

If that doesn't help, and you want to start looking at caps, I would suggest looking at power supply bypass caps first. There may be some PLL or regulator noise getting into the receiver supply rails, or one of the receiver stages could be on the verge of oscillation.