Internal Duplexer Tray; 400 Mhz Notch-Type Duplexers; Bandpass-Type Duplexers - GE Grid Solutions MDS Master Station Technical Manual

Modular communications platform

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minutes for the synchronization process to complete.

Internal Duplexer Tray

The duplexer tray can be removed by first removing two screws on the top of the chassis holding

the tray in place. Save these screws. Disconnect all cabling to both the faceplate of the duplexer

and on the back of the unit. Once cabling and screws have been removed, push on the connectors

on the back of the unit to free the tray from the chassis and then slide out the front. To install a

new tray, slide the tray in allowing the connectors to push through the back of the chassis. Use

the same screws to secure the front of the tray to the chassis and then reconnect cabling being

careful to connect TX and RX cables from the Alarm Module to the correct faceplate

connections on the Duplexer Tray.

You can generally change the radio's transmit frequency up to 100 kHz without re-tuning the

duplexer. The duplexers shown in Figure 8-1. 400 MHz Notch Duplexer can be aligned in the

field by experienced technicians using high-quality test equipment. For assistance, contact GE

MDS Technical Support for additional details about tuning.

(Adjustment generally not required for transmit changes up to 100 kHz)

you return duplexers needing realignment to GE MDS, or the original duplexer

manufacturer, for alignment. In some cases, it may be more economical to replace the

unit than to have it realigned.

These duplexers (Figure 8-2. 900 MHz Bandpass Duplexer) typically allow the transmitter

frequency to change up to 500 kHz without undesired results. Since this type of duplexer cannot

be re-aligned in the field, we recommend contacting the GE MDS Technical Support Department

if you suspect a duplexer problem or need one for a different frequency.

MDS 05-6399A01, Rev. F

Figure 8-1. 400 MHz Notch Duplexer

Duplexer alignment is a sophisticated procedure and a duplexer can be

easily damaged if not handled carefully. It is highly recommended that

MDS™ Master Station

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