Chris,
I have had my two JVC VCRs working side by side with my non-learning Cinema 7 (7200). My standard device code is 0067 and I think the other device code was 0041 (the VCR is no longer).

I made use of the JVC AV compulink and whenever I switched to my "B" code device, S-VHS vcr, my receiver would switch to VCR2, the only non s-video input!!
I couldn't swap the "A" & "B" codes as the other VCR was a very simple multistandard (NON-S-VHS) VCR and only understood "A" codes. After a lot of frustration I opened it up to trace the IR circuitry. I didn't 'really' touch anything but I must have zapped something as it never worked again.

If I had known the power of macro's then I'd still have that JVC VCR instead of a panasonic!

Paul B