Treetop Circuits
Owner’s Manual for SB-51 SSB adapter
Version 4
5
Installation
Unplug the receiver from the power source. Do not trust the switch.
Refer to
Fig. 4
for the following steps.
Be particularly careful not to contact the insulation on the wires with the soldering iron. It
melts and burns more easily than modern insulation.
Remove or disconnect C206 (the small capacitor from V114 pin 5 to V110 pins 6 and 7).
Remove or disconnect C204. (100 pF capacitor from pins 6 and 7 to pin 3 of V110).
Remove V110 and its shield. In most radios, the shield base can remain in place, but
remove it if there is insufficient clearance. Mount the clamp as in
Fig. 1
. The lockwasher
goes under the nut. Remove the hold-down from the large capacitor and slide the clamp
down over it as you seat the SB-51 in the socket. Tighten the clamp and replace the hold-
down.
Route the green wires through the chassis as shown. Connect the shorter one (BFO) to
V114, pin 5 and the longer one (AVC) to the terminal strip at the junction of C213 and
R139.
Fig. 4 –C204 has been removed and C206 disconnected. The green wires from the SB-51
have been routed through the chassis beside the large filter capacitor (in the octal socket).
