Park Air Systems 6525, User Documentation

Page: 19 / 54

31-3MDR00HB Page 19 Operation
Draft
Scroll/Select Switch and LCD
The Scroll/Select switch is used in conjunction with the LCD to select most of the MDR's operational
settings. During normal operation, the LCD displays the Main screen. Detailed information regarding the
Scroll/Select switch and LCD is given on
page 21 .
Connectors
Reference Connector
An SMB jack socket that allows a frequency counter to monitor the MDR's reference frequency. This
connector is used only for maintenance purposes. The instructions for checking and adjusting the
reference frequency are given in the Maintenance topic.
Headset/Microphone/Diagnostics Connector
A dual purpose connector that allows either a headset/microphone, or a PC, to be connected to the MDR.
The connector is a 7-pin self-locking DIN socket; the pin-out is shown in
Fig 6 and detailed in Table 1 for
the audio connections, and Table 2 for the PC connections.
A microphone/headset is used to enable the MDR to be operated from the front panel in AM-Voice mode.
Fig 6 Headset/Microphone/Diagnostics Connector Pin-Out
Table 1 Headset/Microphone/Diagnostics Connector - Audio Connections
Pin
Number
Signal
Input or
Output
Description
1 Microphone ground - 0 V.
3 Microphone PTT Input 0 V to PTT.
5 Sidetone/headset drive Output 0 to 3 V pk-pk.
6 Microphone input Input 2 to 35 mV rms on Passive setting and 8 to 140 mV rms
on Active setting to remain in VOGAD range.
7 Ground - 0 V.