Installation Instructions Chapter 4

500-Watt VHF Transmitter Chapter 4, Installation and Setup Procedures
425A, Rev. 0 4-5
Figure 4-2. Chassis Trak Cabinet Slides
Open the rear door. Inspect the interior
of the cabinet for packing materials and
carefully remove any packing materials
that are found. Slowly slide each tray in
and out to verify that they do not rub
against each other and have no
restrictions to free movement.
4.3 Installing the Cabinets and Trays
It may be necessary to adjust the
position of the trays to keep them from
rubbing. This is accomplished by
loosening the cabinet slide mounting
bolts that hold the front of the slide to
the mounting frame of the cabinet and
moving the tray up or down, as needed,
to correct for the rubbing.
The air intake to the 500-watt
transmitter is only intended for room air.
The cabinet should be positioned for
adequate air intake and exhaust; the
opening of the rear door, if present;
access to the trays, including sliding
them out for testing; the main AC
hookup; and the installation of the output
transmission line. The cabinet should be
grounded using copper strapping
material and should be permanently
mounted to the floor of the site using the
holes in the bottom of the cabinet.
Once the cabinet is in place, and the
trays are checked for damage, the main
AC hookup can be made.
Caution: Before connecting the 220
VAC, make certain that all of the
circuit breakers associated with the
transmitter have been switched off.
The main AC input circuit to the 500-watt
transmitter should be a 40-amp, 230-
VAC line, using AWG 6 wire, inside of a
1-1/4-inch conduit.
The 220 VAC input connections are made
to terminal block TB1, which is part of
the AC distribution panel, near the upper
right-hand, rear portion of the
transmitter: terminals 1 and 4 (220 VAC)
and terminal 3 (chassis ground).
The output of the bandpass filter
assembly, which is an “N” connector,
should connect to the transmission line
for the antenna system.
This completes the unpacking and
installation of the 425A 500-watt VHF
television transmitter. Refer to the setup
and operation procedures that follow
before applying power to the transmitter.