I have finished the design and manufacturing of the QSK relay switching board
for the TL-922 amplifier. The board also has built in soft key, (low voltage
low current) switching for your rig keying line, positive keying line, (key
your amp with +5 to +14 volts from your computer or rig) and the voltage
dropping resistor for the step start relay. Please see the schematic.
I have a limited number of boards available for $16.00 each. If there is
interest, I'll also have the input reed relays available. The input relays will
be around $12.00 each. All plus shipping.
You will have to buy your vacuum relays from Max-Gain Systems or other sources.
LOTS of pictures and the schematic of the board mounted in a TL-922 are shown
in this link:
You will have to buy your vacuum relays (RJ1A-26N969) from Max-Gain Systems or
This circuit design is based on the Rich Measures design. Please see:
I have added the switching transistors for switching the LEDs for transmit and
standby. I have also replaced the meter lamps with new high output LEDs as
well. The series current limiting resistors for the new LEDs are on the circuit
The parts list is being completed now. It will have all the part numbers for
ordering the parts from Mouser. www.mouser.com.
For the TL-922 installation, you have to make a couple of very small chassis
This board will also work very nicely in the Heathkit SB-220 among others.
I will ship world wide by US Mail. This is not a business, I'm doing this to
provide a help my fellow amateurs a way to modify their amplifiers for QSK or
very quiet relay switching so shipping will be done when I have available time.
Usually on the weekends.
A very SPECIAL THANKS to Karin, K3UU for her getting me started on this
project! A QST article will most likely be following soon.
Thanks for the time and enjoy.
Jim W7RY w7ry at arrl dotnet
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