Kenwood TM-V708A instruction manual Connecting With A Tnc And Personal Computer, Function

CONNECTING WITH A TNC AND PERSONAL COMPUTER

Note:

◆Turn the transceiver power OFF before making any connections.

◆Do not share a single power supply between the transceiver and the TNC.

◆Keep as wide a separation as possible between the transceiver and the computer, to reduce noise-pickup by the transceiver.

To connect an external TNC to the
transceiver, use an optional PG-5A
cable. The DATA connector on the
front of the main unit mates with the		GND
6-pin mini DIN plug on this cable.
Power￿	Power￿	Antenna
supply	supply

	TNC
Personal￿	TM-V708A	Data￿
Computer		terminal
	PG-5A cable￿
	(6-pin mini DIN)

Pin No.	Pin Name	Function
1	PKD	Packet data input
		• TX data from TNC to transceiver.
2	DE	Ground for PKD
		Packet standby
3	PKS	• TNC can use this pin to inhibit the
		transceiver microphone input while
		transmitting packet signals.
		Output of detected 9600 bps data
4	PR9	(500 mVP-P, 10 kΩ)
		• Also functions as a common pin for
		1200 bps and 9600 bps data output.
5	PR1	Output of detected 1200 bps data
		(500 mVP-P, 10 kΩ)
		Squelch control output
		• Inhibits TNC data transmitting while
		transceiver squelch is open.
6	SQC	• Prevents interference to voice
		communications on the same
		frequency. Also prevents retries.	15
		• Output Level
		Open squelch: +5 V (High)
		Closed squelch: 0 V (Low)

Note:

◆If the external TNC has a common pin for 1200 bps and 9600 bps data input, connect this pin to the DATA connector PR9 pin. Shorting the PR9 and PR1 pins will cause the TNC to malfunction.

◆If DC voltage is input to the PR1 pin, the external TNC may not function. If this problem happens, add a 10 ∝F capacitor between the PR1 pin and the TNC. Be careful with the polarity of the capacitor.

71