[Hallicrafters] SX77 and SX77A

[Glen Zook]

There were no SX-77 or SX-77A receivers built by Hallicrafters.  There were the S-77 and S-77A.  Basically, the S-77 is the same radio as the S-40A and the S-77A is the same radio as the S-40B.  The only difference is that the S-77 and S-77A were "AC/DC" radios which had no power transformer and the heaters were wired in series.

The differences in the receivers will be the same as the differences between the S-40A and S-40B.  You should be able to compare the schematics for those receivers to tell the differences between the S-77 and the S-77A.

Glen, K9STH

Website:  http://k9sth.com


--- On Sat, 7/3/10, Brian Goldsmith <brian.goldsmith at echo1.com.au> wrote:

Greetings to all.I have a SX77A on the bench,restoring it for a friend. I have the BAMA Hallicrafters 77 manual and the SAMs 77 manual but I can find nothing about the 77A.The 77 here has been modded with what appears to be a 6K8 in place of V6 (at first glance,it may be set up as a product detector).Can anyone point me into a more productive area of information about the A version and any possible  mods?