Audio Input Connections
The BST-75 base station transmitter uses an XLR-3F connector with a
“Combo” phone jack. The XLR portion of the connector will accept a
true balanced or unbalanced line level signal up to +20 dBm. The
1/4” phone jack portion of the connector is a dedicated input for a
phantom-powered, two-conductor Electret microphone. The
HM-100 1/4” behind-the-neck
directional boom microphone
is normally used for language
interpretation, but any two-
conductor Electret microphone
may be used in this input.
Audio Adjustments
In order to ensure the highest possible transmission fidelity, the
transmitter must be modulating at least 50% with normal speech
(0 dB on the VU meter). This adjustment is made in the following
manner:
a.
Ensure that the audio source has been optimized for best
signal-to-noise ratio.
b.
The XLR-3 connector located on the back of the transmitter is
used for line level balanced or unbalanced audio source (0 to +20 dBm).
c.
Set the AF Gain Control on the back of the base station to fully
counterclockwise and then, while normal program information is
present, slowly rotate the “LEVEL” control clockwise until the VU
meter on the front panel begins to deflect. Adjustment should be made
so that normal speech or music deflects the 0dB yellow LED. Only very
loud speech or music should deflect the VU meter full-scale into the
last red LED.
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OPERATING INSTRUCTIONS
