Motorola MTR2000 T5544 Instruction / Field Service Manual page 235

Signal Name
5 VDC
8 VDC
10 VDC EX
10 VDC RX
14.2 VDC
28.6 VDC
AC Fail
Antenna Relay
Aux Carrier* or TSTAT
Aux TX Audio
Aux TX Audio Mode (WCI)
Carrier Detect Switch
Carrier SQ Override (WCI)
Chassis GND
Cntrl 14.2 VDC
Coded WL RX Audio
Disc RX Audio
Ext Code Detect
Ext Failsoft (WCI)
Ext PTT*
Ext Repeat* (WCI)
Ext SPI CS1*
Ext SPI CS2*
Failsoft OUTPUT (WCO)
68P81096E46-E
09/30/05
Table 2. Backplane Signal Descriptions
Type
Power +5 Vdc from Power Supply (1.5 Amp maximum)
Power +8 Vdc from Regulator U102-3 (0.4 Amp maximum)
Power +10 Vdc from U101-3 to Exciter Module via SCM (0.3 Amp maximum)
Power +10 Vdc from U101-3 to Receiver Module via SCM (0.75 Amp maximum)
+14.2 Vdc from Power Supply (8 Amp maximum from 500 W power supply;
Power
16.5 Amp maximum from 250 W power supply)
+28.6 Vdc from Power Supply directly to PA - 500 W power supply only (11.5
Power
Amp maximum)
AC status signal from power supply to SCM; Active high indicates AC Mains
Digital
failure
Digital Open-collector control signal from SCM to antenna relay; Low to energize relay
From SCM to MRTI (Aux Carrier*) to indicate RF channel activity (i.e. PA is
keyed or second receiver is unsquelched); Active low (open-collector output)
Digital
From SCM to TCC ("Transmitter Status"); Active high to indicate station is
transmitting at rated power with an acceptable level of reflected power; low for
any other condition; To opto-isolated input in TCC
To SCM; Accepts wideband or voice-band audio from second receiver (selected
Analog
by Aux TX Audio Mode (WCI)
To SCM; Wild-Card Input selects mode of Disc RX Audio output & Aux TX Au-
Digital
dio input
Digital From SCM to indicate carrier present; TTL active high
Digital Wild-Card Input disables carrier squelch gating qualifier; TTL active high
Power Station ground
Analog +14.2 Vdc from Power Supply to Systems connector J5 (0.75 Amp maximum)
Analog Wideband (coded) audio to WIB; 5 Vdc maximum level
Discriminator audio output from SCM; can be switched (by Aux TX Audio
Analog Mode) to be either buffered disc audio or de-emphasized RX audio (300 to
3 KHz)
To SCM from external CIU; indicates code detect to reduce station turn-on de-
Digital
lay; TTL active high
Digital Wild-Card Input for wide-area trunking systems; TTL active high
Digital Interrupt request to SCM to key transmitter; TTL active low
Wild-Card Input controls audio routing in wide-area trunking systems; TTL ac-
Digital
tive low
Digital From SCM to Systems connector; SPI bus chip select; TTL active low
Digital From SCM to Systems connector; SPI bus chip select; TTL active low
Wild-Card Output; active during failsoft to signal console in coded systems;
Digital
TTL active low
CLN1202 Station Backplane
Function/Signal Levels
5