Hardware Projects » osmo-clock-gen

Assuming most "serious" people playing with SDRs and/or measurement technology have a 10MHz source of some sort (GPS-DO, Rubidium, or "just" a calibated OCXO), the next problem is typically how to generate the paticularl frequency that is required by a given device. By far not all devices are able to deal with a 10MHz reference, including LimeSDR-mini, RTL-SDR, to name a few.

Jack Zimmerman has designed + released an OSHW Si5351C board at https://www.jackenhack.com/si5351c-i2c-frequency-clock-generator-breakout-board/ which looks quite promising. I'm currently trying to ge a PCBA from him so we can play with it.

Should this be doing what we want from it, I think the next step is to create a slightly extended version of the board, which

• includes a small microcontroller with some firmware to drive/initialize the Si5351
• provides a UART (3.3V on osmocom-style 2.5mm jack?) and/or USB to talk to it
• contains some non-volatile storage to store settings and be able to start up autonomously with a given configuration.

If we build a small batch of those boards, the per-board price will be low enough so one can simply have "one per required output frequency" and plug them in as needed, as opposed to using an expensive, large signal generator with UI (and possibly Fan, etc.).