Bosch Security Systems M517 Beltpack Transceiver User Manual 7 30 02
Bosch Security Systems, Inc. Beltpack Transceiver 7 30 02
User Manual
Telex Model TR-825 Beltpack
Owners/Users Manual (Preliminary Information).
General Description:
The Telex Model TR-825 Beltpack Transmitter/Receiver(s) is a component
of the BTR-800 Wireless Intercom System. The TR-825 is intended for use
as a belt worn wireless mobile intercom radio for use in a professional installation such
as television or cinema production.
Each BTR-800 base station can be used with one to four TR-825 units per base station.
The TR-825 operates within the 470 to 608 and 614 to 746 MHz range. (TV Channels
14-36 and 38-59).
The TR-825 transmitter operates on a single frequency within the above range and the
receivers operate on two frequencies contained within an 18 MHz wide section of the
above frequency range.
Typical transmitter conducted output Power is 50 mW. The TR-825 transmit power is
automatically reduced when the unit is close-in to the base station to aid in
intermodulation reduction and unnecessary transmit power.
Operating frequencies can be selected from pre-set groups or the user can
select special operating frequencies within 18 MHz wide allotments.
The talk buttons on the top panel can be switch selected to operate in the
Push-to-Talk mode or the Push-to-Transmit mode.
The microphone gain control, along with the LCD Display, talk function
switch and frequency/group controls are located on the back panel.
The ON/OFF/Volume Controls, Talk Buttons, Low Battery,
Modulation Indicator and the Talk Light are located on the top panel.
Wireless Talk Around and Stage Announce buttons with their indicators are also on the
top panel.
Transmit and Receive antennas are attached to the TR-825. Either or both antennas can
be unscrewed for field replacement but are not coaxial connectors.
The TR-825 beltpack can be powered by AA Alkaline or a Nickel-Metal Hydride Battery
pack.
TR-825 Users/Owners Manual Page 2
TR-825 Controls / Operation
1. I/C A On/Off Volume Knob
Operation: Either I/C “A” or I/C “B” knob turns beltpack on. Both knobs must be off to turn the
unit off. If only one knob off, then only that I/C channel is off for both transmit and receive audio.
2. I/C A Talk LED
Operation: Activated when “A” talk button pressed and “A” I/C knob on. Also activated if “A”
I/C knob on and WTA (default set to A or both) button pressed.
3. I/C A Talk Button
Operation: Press to send audio to transmitter.
4. WTA (Wireless Talk Around) Button
Operation: Press to send audio to transmitter. Software selectable default as to which I/C
channel, or both, is activated along with the WTA button if no talk button is on.
5. WTA LED
Operation: Activated when WTA button pressed.
6. SA (Stage Announce) Button
Operation: Press to send audio when SA button pressed.
7. SA LED
Operation: Activated when SA button pressed.
8. BAT/OM
Operation: Activated when battery voltage drops below 6.5V or audio limiter is activated.
9. I/C B Talk Button
Operation: Press to send audio to transmitter.
10. I/C B Talk LED
Operation: Activated when “B” talk button pressed and “B” I/C knob on. Also activated if “B”
I/C knob on and WTA (default set to B or both) button pressed.
11. I/C B On/Off Volume Knob
Operation: Either I/C “A” or I/C “B” knob turns beltpack on. Both knobs must be off to turn the
unit off. If only one knob off, then only that I/C channel is off for both transmit and receive audio.
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TR-825 Users/Owners Manual Page 3
Specifications:
Input Power…………………………………9.0 VDC Alkaline or NiMH.
Antennas……………………………………Attached.
Channels, two separate receive, one transmit, frequency agile, 25 KHz steps, within
18MHz wide allotments.
Frequency Range……..470-608 and 614-746 MHz.
(within 18MHz wide allotments).
Transmitter:
RF Power Output……………………………………….50 mW typical.
Frequency Deviation……………………………………+/- 40 KHz Peak.
Audio Frequency Response……………………………..300 Hz to 8 KHz.
Microphone input level……………………..8 mV for 40 KHz Deviation.
Receivers:
Sensitivity……….0.8 uV typical, 1.1 uV maximum for 12 dB SINAD.
Squelch………………………………………Opens at 20 dB SINAD.
Modulation Acceptance……………………………..40 KHz Nominal.
Audio Frequency Response……………………………..300 Hz to 8 KHz.
Audio Output (headset)……………………………40 mW, 600 Ohms (1% Distortion).
END