The Si570 is a combined silicon oscillator, that has come to fame in amateur radio circles through its adoption in the SoftRock series of SDRs (or should it really be SDxs)

Silicon oscillators have the property that they are stable, but cannot be manufactures to a precise frequency in the way that quartz can. The Si570 however has an integral frequency synthesizer and so in a tiny package provides oscillator with a computer controlled output frequency.

G4EOP has several interesting pages on the Si570 including some PIC code.http://g4oep.110mb.com/channels/channels.htm

The Crawley Amateur Radio Club hosted another very successful and enjoyable Microwave Table on September 12th, when yet again we were favoured with good weather and a good attendance which encouraged participants as in previous years to spill out during the informal sessions into the open air on to the forest area immediately surrounding the Clubhouse for ‘eyeball’ chats or outside demonstrations etc.

This event is one of several organised each year at different venues in conjunction with the UK uWave Group and we again had visitors from a wide area of the South and South-east, Oxfordshire and East Anglia with a total attendance of around 45 including CARC members which meant that we had pretty well a full house for the formal technical presentations in the afternoon session.

The general format was similar to that of previous years with an informal session in the morning with tables laid out for the ‘bring and buy’ sale in parallel with an exhibition of home constructed equipment being entered into the competition for the annual G3VVB trophy.

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