User's Manual

IV-1
Section IV – RF Components
Amplifier Pallets
The driver pallet is the PA25-VHF-L (low-band channels 2-6) or PA25-VHF-H (high-band channels 7-13) and
is a two stage linear class A amplifier and is characterized with a typical gain of 40dB (low band) or 34 dB
(high band) and absolute maximum drain current of 4.0 A.
The final amplifier stages are comprised of (2) P400-VHF-L or P400-VHF-H amplifier pallets and are each
characterized with minimum gains of 18 dB (low band) or 15 dB (high band) and maximum drain currents of
28 A (low-band) or 20 A (high-band).
All currents on the driver and final stages can be measured across the on-board shunt resistor (0.01-ohm)
found at the DC supply inputs. With this resistance, a 1mV reading across this resistor indicates a current
draw of 1.0A.
All amplifier pallets must have the transistor drain voltages reach at least 26Vdc before the RF drive is applied.