I too have built Rich Measures circuit for both of my TL-922s. However,
because I had two identical amps to modify, I designed two sets of pc boards
to fit into each amp. The larger of the two boards contains all of the
switching and step-start circuitry. I also incorporated circuitry to
restore the functionality of the standby & on-air lights. The pc board
mounts to two of the four bolts that hold the filament transformer and fits
into the space available after removing the original zener bias diode and
heatsink.
The smaller circuit board holds the reed and vacuum rf relays and mounts
directly over the hole vacated by removal of the original bias switching
relay (between the rf in & out jacks). This was a departure from Rich's
suggested approach, but it works great. However, because the relays are
mounted to a pc board which is mounted to the chassis, it is not as quiet as
Rich's suggested mounting technique.
If anyone is interested in the pc boards (for modifying the TL-922), let me
know...
73 de Don (ki6sz)
ki6sz@compuserve.com
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