Operating Instructions; Front Panel Controls And Indicators; Ptt; Line - RF Technology Eclipse Series Operation And Maintenance Manual

1 OPERATING INSTRUCTIONS

Changes or modifications not expressly approved by
RF Technology could void your authority to operate this
equipment. Specifications may vary from those given in
this document in accordance with requirements of local
authorities. RF Technology equipment is subject to
continual improvement and RF Technology reserves the
right to change performance and specification without
further notice.
1 Operating Instructions
1.1

Front Panel Controls and Indicators

1.1.1

PTT

A front-panel push-to-talk (PTT) button is provided to facilitate bench and field tests
and adjustments. The button is a momentary action type. When keyed, audio from the
line input is disabled so that a carrier with subtone is transmitted. The front-panel
microphone input is not enabled in this mode, but it is enabled when the PTT line on
that socket is pulled to ground.
The PTT button has another function when transmission is keyed up, and the TX LED
light is showing. If there is a "forward power low" alarm (the ALARM LED flashes
three times, then pauses), pressing this will cause the ALARM LED to flash 6, 7, 8, or 9
times before the pause (see Table 2). This will indicate what has caused the low power
alarm.
1.1.2

Line

The LINE trimpot is accessible by means of a small screwdriver from the front panel of
the module. It is used to set the correct sensitivity of either line input or the direct
audio input. It is factory preset to give 60% of rated deviation with an input of 0dBm
(1mW on 600 Ω equivalent to 775mV RMS or about 2.2V peak-to-peak) at 1kHz. The
nominal 60% deviation level may be adjusted by measuring between pins 6 and 1 on the
test socket, and adjusting the pot. By this means an input sensitivity from approximately
-12dBm to +12dBm may be established.
An internal, software selectable, option, provides an extra gain step of 20dB. This,
effectively changes the input sensitivity to –32 to –8dBm.
RF Technology T50
WARNING
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