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Phone: 216-265-2315 Fax: 216-267-2915
www.mentorradio.com
(11/11)
M2115 OWNERS MANUAL
Solutions for Advancing Communications
M2115 PIN
DB-25 PIN
FUNCTION
COLOR
10
1
Mic PTT
Gray
8
2
Mic Audio
Violet
2
3
Ground
Black
2
4
Ground
Black
2
5
Ground
Black
2
6
Ground
Black
12
7
4 Ohm RCVR out
Green
12
8
4 ohm RCVR out
Green
3
9
500/600 Ohm RCVR out
Green
9
25
+12 VDC Switched
Yellow
7
11
F1
Orange
1
12
F2 (No External PA)
White-Blue
4
13
F3 (No External PA)
White-Blue
5
14
F4
White-Yellow
6
15
F5
White-Red
1
N/A
FWD PWR DET (External PA)
White-Orange
4
N/A
REV PWR DET (External PA)
White-Blue
Figure 2 - M2115 Power Plug / Remote Cable (DB-25 plug)
Figure 2 shows the functions of the remote connector pins using a 25 pin D-subminiature type connector cable.
Connections to the mating connector may use #22 AWG.
Note:
There are four ground terminals and two terminals for the
4 ohm receiver audio output. The ground terminals may be used as needed for various remote connections; in some
circumstances it may be desirable to “double-up”, using two ground pins in parallel (Each pin is rated for 1 ampere). The 4
ohm audio receiver outputs can be used with one 4 ohm or two 8 ohm external speakers. The +14 VDC is available to
operate external remote control equipment. The 500/600 ohm receiver audio output can be used for remote stations or
for a tape recorder output.
The remote microphone audio input should be in the range -10 to -16dBm (0.3 to 0.15 V RMS). If this voltage is too high
the modulation may be distorted when transmitting—that is, the voice transmissions may not sound as clear.
From the table above it can be seen that the number of remotely selectable frequencies drops from 16 to 7 when an
external PA is used for the 25W and 50W radios. Take this into account when selecting which system is best for your
application.
