MFJ MFJ-1270C - Radio Interfacing; MFJ TNC Radio Port

MFJ-1270C/1274C MANUAL RADIO INTERFACING
Page 20
RADIO INTERFACING
Computer interfacing, covered in the previous chapter, is only half the
interfacing task. The other half is connecting your MFJ TNC to your radio.
MFJ TNC Radio Port
Interfacing the MFJ TNC to your radio involves connecting the following signals
at the TNC Radio Port as shown in Fig. 3-1.
Pin 1 Microphone audio, from the MFJ TNC to your transmitter.
Pin 2 Ground
, audio and PTT common.
Pin 3 Push-to-talk
, to allow the MFJ TNC to key your transmitter.
Pin 4 Receive
audio, from your receiver to the MFJ TNC .
Pin 5 Squelch
input
(optional) to allow the MFJ TNC to detect activity on a
shared-mode channel.
Fig.3-1 TNC Radio Port Connector