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Command to transmit via COM port (RS 232)

The following photos show how a simple adapter (interface) can be made between a radio and a PC. A 9 pin connector has DTR on pin 4 and pin 5 is GROUND. (GND)

These are the components used in the circuit:
R1 = 330 Ω (Orange, Orange, Brown) (Resistor)
R2 = 12 Ω (Brown, Red, Black) (Resistor)
R3 = 1 kiloΩ (Brown, Black, Red) (Resistor)
R4 = 1.5 kΩ (Brown, Green, Red) (Resistor)
C1 = 4.7 microfarads (capacitor)
D1 = 1N4148 (diode)
T1 = BC549 (transistor)

2 stereo plugs for connecting to the sound card.
1 sub-d connector female for the COM port.
1 or 2 plugs for the P/D, depending on its model.

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Settings for the FRN Client


The photo shows how to set up the FRN program to send the command through a COM port. Don't forget to disable VOX on the R/D. Select "Settings-->Adapter" (interface) to open the interface menu.

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Alternative circuits for adapting transceivers with a computer (interfaces).

1. Simple interface for handheld wireless.

2. Simple interface for mobile or base wireless

3. Interface  without common grounding (galvanic isolation) for mobile or base wireless.

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