A variable-frequency local oscillator for the frequency-hopping technique

The frequency hopping technique described elsewhere requires the use of a local oscillator whose output frequency may be rapidly and accurately changed by a fixed frequency increment. Such a device, capable of producing 16 different frequencies separated by 50 kHz over the range of 35.02 to 35.77 MHz, has been built for the Urbana MST (mesosphere stratosphere troposphere) radar facility. The design and construction of that device is described and illustrated.