User's Manual

V H F A M P L I F I E R T E C H N I C A L M A N U A L
2
Specifications
Our vhf amplifier have been designed with government agencies in mind. These are our
highest level of performance and quality for continuous duty solutions while providing
maximizing coverage.
Available in rack mount, nema stainless steel, or painted steel nema enclosures.
Block Diagram Details
- The Uplink amplifier path receives signals form the donor antenna, and then amplifies
them as they pass through the unit to the distribution system.
- The Downlink amplifier path receives signals from the distribution system, and then
amplifies them as they pass through the unit to the donor antenna.
- An Output Level Control (OLC) allows attenuation to be automatically added to
maintain proper factory set output signal. The output signal is sampled after the output
power amplifier, then that RF signal is converted to a DC voltage and delivered to the
OLC. A voltage chart is supplied with the unit for the user to identify input signal
overload. A simple volt meter in needed.
- RF samplers are located just before the Output connectors to give indications of output
level.
- The Factory installed UPS/Battery system is for inconsistency in the AC line power,
Brown outs (low AC voltage for short intervals), Surge protection, short Black outs
(30min or less), crossover time from line AC to Generator power, Circuit breaker for
short circuit and over load protection.
- The first amplifiers in each of the input paths are low level preamps with low noise
figures used to increase the gain of the signal.
- Power Amplifier Class A. This is amplifier is heat sink mounted and produces a high
compression point and 3
rd
order Intercept point.
- 2 Power Supplies are used to separate the DC power consumption for Uplink and
Downlink
- Dropping resisters are used to reduce the 24VDC from the power supplies to a safe
range for the 2 low level amps and OLC. These are also separated for Uplink and
Downlink.
- 3 and 6 dB pads are supplied for gain reduction in the event that the OLC is activated
in the Uplink or Downlink paths.