
DANIELS
ELECTRONICS LTD.
TM
5-4
IM10-VR3H040-AB VHF Enhanced Extra Wideband Receiver Instruction Manual
5.1.5
21.4 MHz IF / Audio Board Interconnect Pin Definitions
The IF / Audio Main Board employs a 48 pin Eurostandard connector for interfacing to all
transmitter power, audio, and control functions. The following are the IF / Audio Main Board
back plane connections to the M-3 Motherboard.
Pin Name
Pin Name
Pin Name
D2
Relay 1, normally open
B2
+13.8 Vdc
Z2
+13.8 Vdc
D4
Relay 1, common
B4
Auxiliary Speaker Output
Z4
+6.0 Vdc Output
D6
Relay 1, normally closed
B6
+9.5 Vdc
Z6
+9.5 Vdc
D8
Relay 2, normally closed
B8
No Connect
Z8
No Connect
D10
Relay 2, common
B10 Disc Output (LPF)
Z10 Spare
D12
Relay 2, normally open
B12 COR (Normal)
Z12 COR (Normal)
D14
IMC1
B14 Disc Output (Buffered) Z14
Squelch
Override
D16
IMC2
B16 No Connect (MT-2 +9.5V) Z16 No Connect (MT-2 +9.5V)
D18
IMC3
B18 COR (Opto-isolated)
Z18 COR (Opto-isolated)
D20
Channel Select 0 (LSB)
B20 De-emphasis Audio Output Z20 No Connect
D22
Channel Select 1
B22 Flat Audio Output
Z22 Receiver I/O Spare
D24
Channel Select 2
B24 Signal Strength (RSSI)
Z24 Priority COR (MT-2 AFC)
D26
Channel Select 3 (MSB)
B26 Balanced Output 1
Z26 Balanced Output 2
D28
Synth Tx Data (Output)
B28 Mute
Z28 No Connect (MT-2 Hst Ovd)
D30
Synth Rx Data (Input)
B30 Ground
Z30 Ground
D32
Synth Bootstrap (Input)
B32 Ground
Z32 Ground
5.2
Enhanced Front End Test Points
Vsupply
+ 9.5 Vdc @ 160 mA
Vb of Q1
+ 7 Vdc
Vc of Q2
+ 7.5 Vdc
Vp of M1
+ 9.3 Vdc
Local Oscillator Frequency
RF Fre 21.4 MHz