User's Guide

UHF Amplifi er Instruction Manual
IM23-UT400AMP
1
GENERAL
INFORMATION
Introduction
The UT-3/400 Amplifi er provides the fi nal stage
of RF amplifi cation and fi ltering for the entire
UHF Transmitter UT-3 and UT-4 406 -512 MHz
family. The amplifi er has four distinct frequency
ranges: 406 to 430 MHz, 450 to 470 MHz, 470
to 490 MHz and 490 to 512 MHz as well as two
distinct output power ranges: 0.5 to 2.0 Watts
and 2.0 to 8.0 Watts. The UT-3/400 Amplifi er
is housed in a machined aluminum case that
ensures optimum RF shielding, provides a good
ground, and also acts as a heatsink.
Additionally, the UT-3/400 Amplifi er is equipped
with output power and VSWR sensing lines that
can be individually confi gured as open collector
or linear outputs. The internal VSWR sensor
protects the amplifi er from high antenna VSWR
by approximately halving the amplifi er’s RF gain
when a VSWR overload condition is present.
The UT-3/400 Lowpass Filter Board provides
output fi ltering for the UT-3/400 Amplifi er. The
lowpass fi lter assembly is mounted in a separate
compartment of the amplifi er case in order to
provided maximum attenuation of harmonic and
other spurious signals.