Electrical ?

What? Try explaining that again, with punctuation please.

 

Ok. Removing the belt and loading the alt will cause a V drop then back to available V indication, and then diminish as battery V dwindle. The RF meter on the CB, I can only guess it is due to the unsupported load. I am puzzled why you removed the belt to check anything. Check the output from the ALT at the back of the ALT, at idle and under load at rpm, then check it at the batteries and check the connections. V should increase with load and rpm, if it is dropping off, check for a poor case ground or ground wire connection. If that is OK, then it may be that the brushes inside the ALT are worn out it is time for a rebuild/replacement.

 

Check and clean your grounds. Especially the terminal ends on the cables / wires. By that I mean the wire itself where it comes into the connector.

 

The rf meter is going up due to poor grounding. Is the cb grounded to the power studs? If so, try putting an inline filter or going straight to the battery. And as mentioned above, clean and tighten all your grounds. The batteries fully charged should be 12.6, the alternator should really be between 13.4-14.2 charging at normal rpms. Honestly, 13.8 would be better for the low range. Your voltage regulator may be getting ready to go inside the alternator.

 

I'm not good with posting links,so use the search in the top right corner. Put in "voltage drop" one on the first page,one on the second page to point you in the right direction.