7.2 Antenna Unit
7-15
- VBW-A, B
Tuning circuits are switched to achieve the required bandwidth for improving S/N
of video signals. They are switched according to pulses of S1/2, M1/2/3 and L
pulse.
- STC DETECT
This is a signal to create the AUTO STC curve.
- MBS ENABLE
This is a signal to reduce main bang caused by leaked TX signal. The gain at Q4 is
reduced for the set time. This is the setting of the gate time in [Menu] -> 0 -> 2 ->
5:MBS. This operation starts a little earlier than the TX trigger.
- TUNE IND, TUNE GAIN /TUNE GATE /SAMPLE HOLD
TUNE IND signal generated from main bang is used for indicating TUNE bar and
AUTO TUNE function.
TUNE GATE signal activates U4 only during reception of main bang. SAMPLE
HOLD signals control U6 (analog switch) and C28, and detected signals are
sampled and outputted as TUNE IND signals. TUNE GAIN signals serve to
compensate the levels. Since the pulse height of the short pulse is lower than that
of the long pulse, the gain is increased during the period of short pulses.
- D MONI OUT
MONI OUT signals are monitor signals of the MIC. Self-test is executed by
[Menu] -> 9 -> 8 -> 2 to check values in RF MONITOR.
- PIN ATT CONT
This is not used at present.
- TUNE
This is TUNE control signal inputted into MIC.
To Next Page
Loading...
