A Chinese ham rebuilt his 1.6KW SSB transmitter.here:
Final tube(FU-728) and socket,blower has been missed.so he had to
replace it to a 4-1000A(7F25B). The right is Chinese 400W SSB transmitter,
Final is a pair FU-250F(4CX250FG).Two transmitters was devoleped in early
1960s, and similar Collins 618T or 618T+30S1.
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