User's Manual

3300-Watt VHF Low Band Transmitter Chapter 3, Installation and Setup Procedures
335B, Rev. 0 3-6
This completes the unpacking and
installation of the 335B 3300-watt VHF
television transmitter. Refer to the setup
and operation procedures that follow
before applying power to the transmitter.
3.4 Setup and Operation Procedures
Initially, the transmitter should be turned
on with the RF output at (A16-J2) of the
coupler assembly terminated into a
dummy load of at least 3300 watts. If a
load is not available, check that the
output of the coupler assembly is
connected to the antenna.
The baseband audio and video inputs and
any remote control connections must be
made to the (A12) A/V input and remote
interface assembly. The baseband
balanced audio input connects to the
terminal block TB1 or the composite
audio input connects to the BNC jack J6.
Connect the baseband video input to the
BNC jack J2.
NOTE: If your transmitter does not
contain the 4.5 MHz composite input kit,
the following description does not pertain
to your transmitter. The baseband audio
input can remain connected when the
4.5-MHz composite input is in use
without affecting the operation of the
tray. Connect the baseband video input
to BNC jack J2 on the A/V input and the
remote interface assembly. If the
(optional) 4.5-MHz composite input kit is
purchased, connect the 4.5-MHz
composite input to the BNC jack J2. To
use the 4.5-MHz composite input, the
4.5-MHz composite input must be
connected to J2 and the baseband select
must be removed from J7-6 and J7-7 on
the rear of the VHF exciter tray. To use
the baseband video and audio inputs, the
baseband video input must be connected
to J2, the baseband audio must be
connected to the proper jack, and the
baseband select must be connected from
J7-6 and J7-7 on the rear of the VHF
exciter tray.
If the (A12) A/V input and remote
interface assembly is not present in the
system, connections are made directly to
the rear of the VHF exciter tray.
Connect the baseband balanced audio
input to the terminal block TB1 or the
composite audio input to the BNC jack J3
or J13 on the rear of the VHF exciter.
The baseband audio input can remain
connected when using the (Optional) 4.5-
MHz composite input, if present, without
affecting the operation of the tray.
Connect the baseband video input to the
BNC jack J2 or J1 also on the rear of the
VHF exciter or, if the (optional) 4.5-MHz
composite input kit is purchased, connect
the 4.5-MHz composite input to the BNC
jack J2 or J1. To use the 4.5-MHz
composite input, the 4.5-MHz composite
input must be connected to J2 or J1 and
the baseband select must be removed
from J7-6 and J7-7 on the rear of the
tray. To use the baseband video and
audio inputs, the baseband video input
must be connected to J2 or J1, the
baseband audio must be connected to
the proper jack, and a baseband select
must be connected from J7-6 and J7-7.
Switch on the main AC for the
transmitter and the circuit breakers
located on the rear of the VHF exciter,
and on the front of the three VHF
amplifier trays. On the VHF exciter tray,
switch the Operate/Standby switch to
Standby and the Auto/Manual switch to
Manual. Normal operation of the
transmitter is in Automatic, which uses
the video input to the VHF exciter as an
Operate/Standby switch. In Auto, if the
input video is lost for approximately 7
seconds, the transmitter will
automatically revert to Standby and,
when the video signal is restored, the
transmitter will quickly return to Operate.
Move the Operate/Standby switch on the
VHF exciter tray to Operate. This will
apply enables to the switching power
supplies in each of the VHF amplifier
trays. Observe that a power supply
voltage reading of +28 V is on the front