User's Manual

Technalogix Ltd TAVD-500 Transmitter
IV-1
Section IV – RF Components
Amplifier Pallets
The VHFTV-25 pallet is a two stage ultra linear class-A linear pallet. The VHFTV-25-L has a typical
gain of 36dB and the VHFTV-25-H has a typical gain of 34dB. These pallets draw no more than
3.5Adc total drain current (the exact bias and drain currents of your system are found in the spec
sheet supplied with each manual). The quiescent and drain currents can be measured on the
VHFTV-25 pallet by measuring the voltage drop across the current sense resistor found directly at
the DC power supply lead input to the pallet. This resistance is 0.01-ohms, providing a 10mV per
ampere ratio.
The VHFTV-200 pallet is a two stage ultra linear class-A linear pallet. The VHFTV-200-L and –H
pallets have a typical gain of 20dB and the VHFTV-200-H has a typical gain of 18dB. These pallets
draw no more than 4 Adc total drain current (the exact bias and drain currents of your system are
found in the spec sheet supplied with each manual).
The final amplifier stage is comprised of a VHFTV-400-L or VHFTV-400-H amplifier pallet and
are characterized with typical gains of 18 dB (low band) or 16dB (high band) and maximum
drain currents of 17 A (low and high band) for 8VSB systems.
Each of the amplifier pallets is connectorized. All amplifier pallets must have the transistor drain
voltages reach at least 26Vdc before the RF drive is applied.