The Avtech AVD1 is a fixed-tuned unit for the frequency range of 400 to 1500 MHz, but the AVD1 modules are much smaller (1.1" x 1.3" x 2.3") than the AVD modules (1.7" x 2.6" x 4.2"). The pulse repetition frequency of -C units is variable from 100 Hz to 1 MHz using the internal clock oscillator that is controlled by a four-position range switch and a one-turn control.
