Re: 40MHz OCXO board sold at RAL

Gareth G4XAT

I bought one of these boards and based on the supplied description fed a suitable voltage the the LDO reg. Yes, it gets warm with too much overhead, but easily solved with a 2A 7805. And it works fine....

Also well worth the purchase price was the 4 sets of driver and PA sections, perusal of the data sheet shows great promise as making perfect pre-drivers for the NEC ex DATV amplifier pallets that have now escaped into the amateur world via Neil and others.
The pre-driver just needs 5V, the PA is rated to 7V and includes some sort of bias input. Its not clear from the data sheet (to me) quite how that should be produced (a 10K pot across 5V??), or what its range should be. It looks like there are some bias switching sm transistors on the PCB.
Any chance of a circuit for the amp part of the board, or at least a bit more spec on the PA chip (like bias vs gain/linearity/power etc)? I'm particularly hoping for best gain and linearity as if the chain will deliver +30dB of gain, it will allow saturation of one of the NEC pallets from a mere ADALM Pluto driver, so perfect of Langstone/Portsdown usage. With 5 watts it might even drive a pair of them.....

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