User's Manual

GMH Series VHF Radio General Information
BK RADIO Page 4-7
4.3.6 VCO Board
The VCO is a varactor tuned feedback oscillator using Q1 with feedback from tapped auto transformer T1.
A steering voltage is used to set the capacitance of CR1, CR10, CR11, and CR12, which in turn controls
the frequency of oscillation. CR3 provides a low sensitivity input for modulating the carrier frequency.
The cascode amplifier comprised of Q6 isolates the VCO from its load and provides a nominal drive level
of 0 dBm in receive and transmit.