Table 4. System Connector - Commonly Used Pins - Motorola MTR2000 T5544 Instruction / Field Service Manual

Pin Function
Name
RdStat TTL compatible logic output
indicating Rx. Activation status.
Disc. Rx. Unfiltered and unsquelched
Audio discriminator audio without de-
emphasis.
RSSI DC output volts related to
received carrier level.
Cntrl 14.2V 14.2 volts dc output.
For dc-only 250W power
supplies, this voltage is equal to
the input supply voltage.
5 V 5.1 ± 0.25 volts dc output.
GND Ground.
Aux.Tx Tx. modulation input from
Audio external source.
Ext. PTT External Tx. keying signal.
AC_Fail Logic output to indicate failure of
AC line input.
Wireline
Pair 3+/–
Additional wireline for other
functions.
Wireline
Pair 4+/–
68P81096E37-N
06/28/05
Table 4. System Connector – Commonly Used Pins
Description
Pin #
C2, B21, 0.0 to 0.2Vdc with squelched receiver,
B3/C3 4.8 to 5.2Vdc with unsquelched receiver.
C17 80mV minimum to 400mV maximum for 60%
system deviation. Output level is RSS
programmable.
C11 Typically 0.5Vdc for –120dBm to 3.5 Vdc for –
40 dBm carrier. Variation with carrier level @
approximately 40mV/dBm.
A18, B18, C18 Total current through all of these pins should not
C32, B32, C32 exceed 1Amp.
A20, B20, C20 Total current through all of these pins should not
exceed 500 mA.
A19, B19, C19 Total current through all of these pins should not
A27, B27, C27 exceed 1.5 Amp.
A31, B31, C31
A17 RSS programmable sensitivity.
For R03.01 (host software) and earlier, the fixed
sensitivity is @ 172 mVrms for 60% system
deviation.
RSS programmable for pre-emphasized
or flat response. DC offset +2.4V. High
impedance input.
C10 Grounding Ext. PTT pin causes Tx to key.
5.0Vdc on pin when Tx is not keyed.
Note: To transmit signalling code (PL / DPL)
by external PTT, it should be mapped (via RSS)
to Wireline, and external modulation input
should be routed to wireline.
A4 Requires a Battery Revert dc supply. Line goes
high (5.0Vdc) if AC fails.
C28, C30
Line sensitivity and operation identical to line
pairs 1 and 2 (see Table 10).
B28, B30
Pin Signal Characteristics
Installation
33