One of the current projects is to build a radio module to be a replacement for the excellent, but large and expensive, Radiometrix NTX2.
A first prototype uses the Micrel MICRF112 10mW FSK transmitter with a varactor controlled crystal pulling arrangement. An onboard variable capacitor also allows tuning of the centre frequency to anywhere in the LPD433 ISM band.
This prototype was soldered up today and is working well. We hope to develop this technique further to produce a cheap & reliable radio capable of MFSK and DominoEX as well as the standard 50/300 baud RTTY.
