[Premium-Rx] RA6778C

[Dan Rae]

Just to add to Tom's excellent summary.    And I agree totally about the 
eproms.  When I got my 6778A one of the eproms was blank, but thanks to 
a member of this list I was able eventually to replace it and bring the 
radio to life.

This highly screened radio and it's predecessors, the cpu containing 
6778A and B and the earlier non micro 6772E were designed to be used in 
situations where Tempest Proofed radios were required.  As a result the 
6778C production continued up to at least the late eighties in parallel 
with the 6790/GM whose cpu board the 6778C in fact uses.   All use the 
classic signal path and conversion scheme originally designed for the 
RA1772.

If you have the TCXO standard version they all seem to have failed by 
now, due to the poor quality of the OEM part used. 

Incidentally the non leaking Varta NiMH version of the prone to leak 
nicad is available in the US from Mouser, and makes a better, drop in, 
replacement for it here and in the 6790/GM also.

73
Dan
ac6ao / g3ncr