Owner`s manual

www.mentorradio.com
Phone: [phone] * Fax: [phone]
M15-OM-11/11
REMOTE OPERATION
The 25 pin D-subminiature type connector on the rear panel contains all the connections needed
for various types of remote operation. The functions of the different connector pins are as follows:
PIN NO
.
FUNCTION COLOR
1
mic PTT
gray
2
mic audio
violet
3
ground
black
4
ground
black
5
ground
black
6
ground
black
7
4 ohm rcvr out
green
8
4 ohm rcvr out
green
9
500/600 ohm rcvr out
green
10
squelch break
blue
25
+14 v
dc
yellow
Connections to the mating connector can use #22 gauge wire. Note that 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 or two external speakers. The +14 vdc can supply up to 500
ma. to operate external remote equipment.
The 500/600 ohm receiver audio output can be used for remote stations or for a tape recorder out-
put. It’s level is factory adjusted to 0 dBm (0.77 v rms) but may be adjusted internally for any level
from -7 to +10 dBm by trimmer potentiometer R205 on the printed circuit board inside the M15-25.
Both the 4 ohm and the 500/600 ohm receiver audio outputs are unaffected by the volume control
on the M15, the latter affecting only the speaker on the front panel of the M15-25.
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. If this occurs, trimmer potentiometer R207 (on printed
circuit board inside M15-25) can be adjusted to reduce the microphone audio level.
The colors listed above refer to the usual color codes when using Mentor part no. 1101368 6-
conductor remote cable.