GAI-Tronics 1931888-3011 Page/Party to Coupler - Manual (Page 7)

Pub. 42004-245B
Model 1931888-3011 Page/Party
®
to Radio Coupler Page: 7 of 10
\\s_eng\gtcproddocs\standard ioms - current release\42004 instr. manuals\42004-245b.doc
03/08
Time-Out Timers
The coupler is equipped with two timer boards labeled TMR #1 and TMR #2. The function of the boards
is provided to limit the transmission times of both the system and radio.
TMR #1
The TMR #1 board is controlled by the VOX board during party line communication from the Page/Party ®
system to the radio. When VOX control signal is present at TMR #1’s pin 1 (system talk mode), the
output at pin 2 is pulled low to activate the VX1 relay. When party line audio is no longer present on the
line, the VOX output is removed and the VX1 relay drops-out to permit radio response.
However, if the station remains off-hook on the party line and noise levels occur, the VOX will detect the
levels on the line, and key the radio. Under this condition, the timer board will time-out and disable the
VX1 relay to remove radio keying control after approximately one minute.
TMR #2
The TMR #2 board is controlled by SQUELCH control from the radio to Page/Party ® system’s party line
communications. When the SQUELCH control signal is present at TMR #2’s pin 3 (radio talk mode), the
output at pin 2 is pulled low to activate the SQ1 relay.
When radio SQUELCH control and audio is no longer present, the SQ1 relay drops-out to permit system
response. However, if the radio remains in receive mode with SQUELCH control, party line audio cannot
be transmitted back to the radio system. Under this condition, the timer board will time-out and disable the
SQ1 relay to remove radio
SQUELCH control after approximately one minute.
Maintenance
Control Functions
The Model 1931888-3011 Coupler contains four adjustment controls which have been pre-adjusted at the
factory. Minor adjustments may be necessary for optimum system performance. Refer to Figure 5.
Control Description:
• UA
VOL: Adjusts the audio level being coupled to the Page/Party ® or Call/Talk system from the
radio’s speaker out. Clockwise rotation of the control increases the audio drive level.
• RADIO
VOL: Adjusts the audio level being coupled to the radio’s microphone-in circuitry from the
Page/Party ® or Call/Talk system. Clockwise rotation of the control increases the audio drive level.
• VOX
SENS: Adjusts the threshold level (activation point] for the Voice Operated X switch circuitry
to activate. Clockwise rotation of the control increases the sensitivity level.
• TRANSFER
SENS: Adjusts the threshold level for the TRANSFER detection circuitry to activate.
Clockwise rotation of the control increases the threshold level for XFR relay activation when an
associated Page/Party
® station is off-hook.