Ranger modes from Tim, WA1HLR (see last paragraph):
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The T/R control circuit is much more sophisticated than the original Johnson abortion! TWO relays will be needed. I used 24 volt units due to their availability. A typical 4-pole double-throw unit and a larger 3-pole double-throw KCP 11 type 11-pin plug-in type. The 3 pole must have good voltage rating as it performs the following:
1. applies 117VAC to antenna changeover socket.
2. applies screen voltage to the final amp tube or grounds screen during standby.
3. applies low voltage B+ to screens of the modulator tubes, clamp tube screen and drive control pot.
The 4-pole miniature plug-in relay is used for the following:
1. to key the transmitter as done in the original PTT circuit.
2. applies 6.3 volts AC to the red pilot light on the front panel (VFO escutcheon) to let you and any visitors to your shack know that you are ON THE AIR!
The remaining two sets of contacts are brought out to a 6-pin Jones connector or other socket for the control of other devices such as receiver muting or keying up another transmitter when using the Ranger as an exciter. If one wishes to cut corners you can get by with a total of 4 poles of double-throw contacts.
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The complete text is here:
http://www.amwindow.org/tech/htm/rangtron.htm