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How it works
– OS connector Aux 1 tip goes to 12Vdc when Radio 1 goes into transmit mode.
External relay K’s contacts open to prevent transmit audio (from microphone, computer, etc.) and
CW key line (from keyer, computer, etc.) from reaching Radio 2, which will prevent SSB or CW RF
energy from being transmitted by Radio 2.
IMPORTANT WARNINGS:
This approach does not prevent the radio from going into “transmit mode.” While Radio 1 in the
above example is transmitting, Radio 2 can be put into transmit mode by closing a foot switch,
pushing the TX button on the front of the radio, etc. This is acceptable as long as the audio and
CW inputs to the radio are interrupted.
This approach does not prevent the operator of Radio 2 from activating either stored audio or CW
messages inside the radio. If the radio has this capability, it is highly recommended that these
features be disabled.
Specifications
Voltage Requirement
+12 Vdc (nominal)
Current Requirement
100 mA plus external devices
Switched External Devices
12 Vdc at Max. 1A per each of AUX1 and AUX2
Isolation Between Ports A and B (one active):
Frequency (MHz)
Isolation (dB)
1.8 to 7
100
14
95
21
85
28
80
Insertion Loss
0.1db
VSWR
<1.2 at 30 MHz
Operating Time
3 ms
Frequency Range
1.8-30 MHz
Power Rating
200W ICS
Dimensions (HWD)
2 x 5 x 2.25 inches
