ZETRON 748, Technical Manual

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Installation
025-9368H 17
FINAL CHECKS BEFORE LEAVING THE SITE
1. Have someone call the unit and access the modem programming. Verify errors are not present
during modem communication.
2. Place a mobile to telephone call through the Model 748 and verify the audio levels are set
correctly. Place a telephone to mobile call also to verify level setting and DTMF decoding in
both directions.
3. Have someone call the Model 748 and place a call using a rotary phone. Verify proper operation
and decoding of the pulses.
4. Verify that the Model 748 will decode CTCSS and DCS (if used). Using your terminal or PC
direct connected to the local RS-232 port, verify CTCSS/DCS decode. This can be done in real
time by selecting item “11” in the Diagnostic Menu (CTCSS/DCS decode). All the CTCSS tones
and DCS codes should decode without being enabled. If the DCS code does not decode, try
inverting the DCS decode polarity in the System Menu.
OPTIONAL CONNECTIONS
1. AUXILIARY INPUT: J5 pin 9 is the auxiliary input connection. It is internally pulled up to
+12VDC through a 47K ohm resistor. It is an active low input for connection to a logic signal or
relay contacts. This input can be programmed for either Transmit Channel busy indication or Site
status indication. See “Auxiliary Input” in Section 3 for more information.
2. AUXILIARY OUTPUT: J5 pin 8 is the auxiliary output connection. It is an open drain FET to
ground. It will provide a logic signal to ground when active. If relay contacts are required for
your application, K2 and JP15 can be installed after removing JP14. This provides a set of relay
contacts and JP15 provides the selection for NO or NC operation. The common contact is still to
ground. See “Auxiliary Output” in Section 3 for more information. Order Relay kit # 950-9752.
3. PTT RELAY: If your installation requires that the Model 748 provide relay contacts for PTT
connection (the transmitter reV to key), K1 can be installed after removing JP16. This
provides a set of relay contacts on J5 pins 5 (NC), 6(COM), 7(NO). Order Relay kit # 950-9752.
RADIO-SPECIFIC CONNECTIONS
The following pages provide information for connecting specific radios to the Model 748.