Telex TR-825, BTR-800 dimensions Internal Transmit Switches, Intercom Switch, Intercom Interface

Internal Transmit Switches

Internal to the BTR-800 are two transmit switches which en- able a user to turn on or off the two transmitters individually. See Figure 19 for the location. The top cover of the base sta- tion must be removed for access. The switch closest to the front panel controls transmitter 1 (audio channel A). The switch behind that is transmitter 2 (audio channel B). The de- fault switch position is to the left if you are facing the front of the base station. This is the “ON” position for the transmitters.

In the normal use of the BTR-800, there is no need to access these switches. They are used to test the transmitters individu- ally at the factory.

Intercom Switch

The RadioCom® wireless system can be interfaced to RTS, TW, Audiocom® (Telex), Clear-Com®,RTS matrix and other intercom (I/C) systems. Set the Intercom switch on the rear of the unit to the appropriate system and connect the system to the base station. The two intercom channels on the rear of the base station have loop-thru male and female XLR connections for two-wire systems and RJ-11 type jacks for four-wire sys- tems.

This switch only affects the two-wire intercom systems. The functions of the I/C XLRs change depending on the intercom selected. Please see Section 12 for pinout information of the different two-wire intercom systems.

BACK

FRONT

Transmitter 2

ON	S3
	OFF
	S4
ON	OFF
	Transmitter 1

Figure 19

Internal Transmit Switches

Intercom Interface

Telex (Audiocom®) and Clear-Com® intercom systems re- quire one cable for intercom A and one cable for intercom B in order to interface two channels of intercom to the base station. This interfacing is done through the I/C A and B 3-pin XLR connectors on the rear of the unit.

RTS TW intercoms only need to connect one 3-pin cable to one of the four intercom XLR connectors since two channels of audio are carried on one cable. The intercom switch paral- lels the four XLR connectors when in RTS mode. RTS chan- nel 1 is placed on intercom A and RTS channel 2 is placed on intercom B as long as the RTS TW input to the base station is wired as in Section 12.

Four-wire intercom systems require one cable for intercom A and one cable for intercom B in order to interface two chan- nels of four-wire intercom to the base station. This interfacing is done through the I/C A and B RJ-11 type jacks on the rear of the unit. See Figure 20 for the pinout of the RJ-11 jacks.

PIN 6 5 4 3 2 1

NC	NC
AUDIO IN -	AUDIO IN +
AUDIO OUT -	AUDIO OUT +

Figure 20

RJ-11 Type/ Four-wire Pinout

5-6