Amplifier
Setup
3-11
PRELIMINARY - Motorola Internal Use Only
SLE*-* Installation and Operation Manual
2
Position the drive control select jumper (Figure 2-8) temporarily in the
MAN
position and
perform the complete procedure described in Manual Gain Control if not already completed.
3
Position the drive control select jumper to
AUTO
.
4
Connect a signal-level meter to the
FWD OUT
test point and tune the meter to the high-band
edge carrier.
5
Turn the thermal level potentiometer on the SLE-TDU fully clockwise and then reduce to
obtain the level obtained in Step 8 under Manual Gain Control.
SLE-ADU
The SLE-Automatic Drive Unit (SLE-ADU) uses surface acoustic wave (SAW) filters to select a
pilot frequency and then monitors the amplitude of this frequency. Any change in signal level is
fed back to the SLE-Bode equalizer. It is assumed that the encountered signal level changes are
due to changes in cable attenuation and hybrid output associated with a change in temperature.
The SLE-Bode equalizer then changes its insertion loss to maintain a constant output level. The
SLE-ADU (illustrated in Figure 3-6) maintains the most precise output level of the three
available methods.
Figure 3-6
SLE-ADU
AUTOMATIC
DRIVE UNIT
SLE-ADU/ _______________
Pilot frequency
To set up the SLE-ADU:
1
Position the drive control select jumper temporarily to the
MAN
position and perform the
complete procedure described in Manual Gain Control if not already completed.
2
Verify that the frequency stamped on the SLE-ADU control unit is the same as the system
pilot frequency. The pilot frequency is a CW or an available NTSC television channel not
scrambled using sync suppression and not a digital channel.
3
Position the drive control select jumper to
AUTO
.
4
Connect a signal-level meter to the
FWD OUT
test point and tune the meter to the high-band
edge carrier.
5
Turn the auto level control potentiometer on the SLE-ADU fully clockwise and then reduce
to obtain the level obtained in Step 8 under Manual Gain Control.