Hi Garey, Thanks very much for your complete answer. Here's what I found out:
> > First question is what is the serial number of your R-4A? The R-4A serial number is 3956 with no letter behind it. > > What is the letter at the end of the R-4B serial number? The R-4B is 15359 with G behind the number. What is the letter at the end of the T-4XB serial number? The T-4XB is 10382 with R behind the number. BTW, I want to transceive with this pair so the color code is important. The R-4A has no color code on the crystals. The R-4B has a red stripe on a crystal next to the crystal calibrator under the chassis. None of the other crystals are color coded. And the T-4XB has a red stripe on one of five crystals under the chassis. The letters are a color code for the Carrier Oscillator and BFO crystals > in the Tx and Rx. Ideally, the letters (and color stripes on the > crystals themselves, CHECK!) are the same in Tx and Rx. My plan is to keep one of the receivers and sell the other. Will either of these two receivers work on transceive without problems with the T-4XB? Thanks for taking the time to read and answer this. Tom, WA3REY
