|RS-6 Receiver Frequency Spotting Modification|
|Overview: The RS-6 does not have a spotting function. By adding a small momentary push switch you can find your transmitter frequency on the receiver. The B Plus Path is described below. You might want to read some of path description before accomplishing the simple modification. The Receiver modification is below in the last paragraph.|
NOTE: The toggle switch S-301 on the filter Accessory Unit controls the B + for receive and and transmit. During transmit the RS-6 receiver is inoperative.
B Plus Path with S301 TOGGLE SWITCH ON TRANS:
The 415 Volt source from the power supply enters the filter unit at connector PL3 pin 3 and then is connected to terminal 1 of the toggle switch-- In Transmit this switches the HV is switched to to terminal 3 of the switch.
Terminal 3 then goes to the TRANS socket SO5 terminal pin 2. PIN 2 is inner connected inside the transmitter to transmitter PL 5 Pin 6. Pin 6 then supplies B+ back to the Filter Accessory Unit TRANS socket SO5 pin 6 which then feeds terminal 4 of the toggle switch. (Wonder what rocket scientist did this?)
Terminal 4 of the toggle switch then feeds the B + through choke L301 and then goes to terminal 2 of the toggle switch.
In transmit TRANS mode terminal 2 of the toggle switch feeds terminal 5 of the switch which then goes to pin 3 of the TRANS power socket which then finally feeds the B+ circuit for the transmitter. (Your government tax dollars at work.)
The RS-6 radio system depends on the interconnect present in the transmitter between pins 2 and 6. Since the B+ is removed from the receiver you can not zero beat or hear any signal.
B Plus Path with S301 TOGGLE SWITCH ON RECVR:
The 415 volt line goes to terminal 1 of the toggle switch and connects to terminal 4 of the toggle switch which feeds the TRANS SO5 pin 6 which is again inter connected to pin 2 which then returns to the toggle switch terminal 3 which due to the position of the switch is now open.(Wow)
Terminal 4 of the toggle switch also feeds through
the choke L301 to terminal 2 of the toggle switch which due to the position
of the switch in RECVR goes to terminal 6 of the toggle switch and then
feeds the top of the resistor R301 and R303 for the VR's which supply
B+ to the receiver. Terminal 6 also goes to the pin 4 of the TRANS SOS
plug feeding the transmitter pin 4 which goes to the relay. Since the
relay closes during a transmitter condition when the toggle switch is
switched to transmit (the key is up and not closed ) the flow of B+ stops
Receiver Spotting Modification:
You may enable receiver spotting by modifying the wiring on the Filter Accessory Unit. It will be necessary to temporary jumper terminal 5 of the S301 toggle to provide High Voltage to terminal 6 of the toggle switch. Use a momentary push button switch such as a small micro switch. In the photo of the Filter Accessory Unit the white "spotting" wires are going to the toggle switch, Terminals 5 and 6 on the toggle switch are the ones closest to the VR tubes.