User Manual

SECTION 1: THEORY OF OPERATION
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consisting of R30, C45, C28, and C37. The filter integrates the pulses, which normally appear on PDOUT
into a smooth DC control signal for the VCO. The output of U7 is attenuated by module AT1, resulting in
improved VCO stability.
Power Amplifier
The transmit injection signal from the RF injection section is applied to the high-powered linear amplifier
(U1) one (1) watt amplifier. The signal is then routed to the final power amplifier boosting the output
signal to 40 watts. The transmitter output power is controlled with RV2. RV2 controls the output voltage
of a voltage regulator (VR1). The signal KEY* enables the regulator. The output of the amplifier is routed
to transmit antenna port ANT.