Presented here is a 18GHz divide by one thousand prescaler for use with a standard cheap frequency counter. No credit is taken for the circuit design, several versions of this have appeared on the web over the years. I have used a more up to date GaAs divide by eight IC in the front end and designed a suitable pcb to accommodate all the components.
The heart of the circuit is the HMC494 divider IC, manufacturers claim it is good to 18GHz but I have not been able to test this. The divider IC used comes in a 3mm X 3mm QFN package is is quite small so a steady hand is required to solder the chip on the pcb.
The pcb is mounted in a small aluminium die cast box, sma connectors are used for the input and output ports.
The photos show the prescaler using a couple of signal sources; a modified 10.595GHz radar motion sensor that I tuned down to its lowest frequency and 998MHz from a Marconi 2955 test set.
Barry Zarucki M0DGQ
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