A/C Stereo Clicking--Which Relay?

[Bob Reinhardt]

Hello, all,

Once again, I return to you with a radio that pops/clicks when the A/C 
compressor cycles.  The situation: I replaced what I believe to be the 
bad diode on the A/C clutch relay, per the instructions of helpful 
listers Kneale, Mike, and Bernie.  I put the relay back in, but the 
popping/clicking continues--although perhaps not as loud.  Two 
questions, then, and I'd appreciate any help any one can give:
1) Did I replace the right diode?  I have an image on the web that 
shows which one I replaced: http://www.reinhardtmail.net/a_c_diode.jpg.

2) Does this clicking/popping sound happen only when the refrigerant is 
low?

Thanks in advance.

Cheers,
Bob
bobh at reinhardtmail.net