As seen in Electric Radio: A Quartz Crystal Replacement Alternative (Jan 2018)

The four-channel oscillator board makes it easy to apply the Epson SGR-8002DC-PHB-ND programmable PLL frequency sources as a quartz crystal substitute in many radios. The board required 8-18VDC at 100ma and supports from one to four oscillators (Not included.) Any frequency from 1 to 125 MHz may be specified.

A logic "0" or contact closure to ground selects a desired channel. All input and output signals are buffered to protect the oscillators from inadvertent damage. Provision for jumpers and scaling resistors allow interfacing to many circuits without external wiring or components. The output is a 5 volt P-P square-wave that has proven suitable for driving mixers, up- and down-converters, receiver LOs, channelized transceivers and transmitters as a crystal substitute. (External amplification may be required to drive some transmitters to full output; also, these oscillators may not be shifted in frequency such as for clarifier or FM modulation).

The four-channel board is provided as an easy-to-build kit. Overall size is 2" by 2" by < 1/2" high so it can be mounted inside many radios. Suitability for a given application and specification of correct oscillator frequency is the responsibility of the user. With fewer manufacturers providing custom quartz crystals, the four-channel oscillator board is a flexible alternative for many frequency control needs.