Mocomtech CDM-QX Config„Tx„On/Off Transmit ON/OFF Control, Tx Common Output State Off On

Models: CDM-QX

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CDM-Qx Satellite Modem

Revision 5

Front Panel Operation

MN/CDMQx.IOM

If (using the ODU, BUC menus) the user has selected a BUC LO frequency (other than zero) and defined whether the mix is high side or low side, the display will be modified as shown below, to include the calculated Transmit RF frequency of the modem/BUC combination:

Tx IF Freq: 1156.3456 MHz

RF=14156.3456 (◄ ►▲ ▼ ENT)

As the Tx IF frequency is edited the RF frequency will automatically be updated

(Config„Tx„On/Off) – TRANSMIT ON/OFF CONTROL

Tx Output State: On Off

RxTxInhibit Common (◄ ►, ENT)

Select either On, Off, RxTxInhibit, or Common using the WXarrow keys, then press

ENTER.

When Rx-Tx Inhibit (RTI) is selected, it will prevent the TX carrier from being transmitted, until the demodulator is locked.

To avoid the Tx Carrier from being turned off when the demodulator loses lock for a very short period of time, the demodulator must be unlocked continuously for a period of 10 seconds before the transmit carrier is inhibited. This time interval is fixed and the user cannot change it.

Having this feature enabled does not affect the internal IF Loopback feature. But, please be aware that if an external IF Loopback is attempted (connecting IMPORTANT an external cable from the Tx IF output to the Rx IF input), then this will not work! (The Tx carrier cannot turn on until the demod is locked, and the demod cannot lock, because the TX output is off. The net result is that the demod will not lock, and the Tx carrier will not turn on. USE THE RTI FEATURE WITH

EXTREME CARE!

When Common is selected, this sub-menu will appear:

Tx Common Output State:

Off On

(◄ ► ENT)

This will turn On or Off all the transmit path – master control for all modulators.

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Mocomtech CDM-QX operation manual Config„Tx„On/Off Transmit ON/OFF Control, Tx if Freq 1156.3456 MHz RF=14156.3456 ENT