MFJ Enterprises MFJ-1707 Instruction Manual

MFJ-1707 Instruction Manual RF Sense T/R Antenna Switch
INTRODUCTION
The MFJ-1707 RF Sense T/R Antenna Switch senses transmitted RF and
switches your antenna from the receiving antenna to the transmitting antenna
using a relay. It shorts your Transciever input to ground to protect your
transciever. It provides an auxiliary contact closure to ground during receive
(opened in transmit) for an "On-the-Air" sign or other use. It also has a control
line input, which lets your key/keyer or PTT line switch the antenna.
An adjustable time delay circuit gives you delayed switching. This prevents
your antenna from switching between dots and dashes or between syllable and
words.
TECHNICAL DESCRIPTION
The MFJ-1707 RF Sense T/R Antenna switch uses a relay, which switches from
transmit to receive mode. When no power is applied to the unit, it is in the
transmit mode. Once power is applied the relay switches on and the unit is in
receive mode. When the unit senses RF or the control line is grounded from a
keyer or PTT switch, it switches the relay off and the unit is in transmit mode.
The delay adjustment allows you to change how fast the relay switches back to
the receive mode. It is adjustable from 0 to 2 seconds.
The auxiliary jack provides a contact closure to ground during receive (opened
in transmit) for an "On-the-Air" sign or other use.
The MFJ-1707 RF Sense T/R Antenna switch requires 12 VDC or 110 VAC
with MFJ-1315 power supply.
CONTROLS
POWER ieee sacehtetace Saat aed Senais 2.1mm Coaxial power input jack with center pin
positive and shield negative
(COMON c i249 bs sonia rent yaad RCA input jack
PUN es Pertti hee aetna thee ee RCA input jack
(=): \ ae nr ree Controls time delay for switching
Transmitting Antenna............ SO-239 Coaxial connector
TYANSCIEVED 5. 2s cetera seecaaates SO-239 Coaxial connector
Receiving Antenna................ SO-239 Coaxial connector