Si570 Project
SI570 Daughtercard -- $45 (bare board - $4)
Control Board -- $45 (bare board - $8)
Both Daughtercard and Control Board together -- $80
Click on the photos to enlarge
AA0ZZ has developed a 10 - 157 MHz DSPLL VFO using the Si570 chip from Silicon Labs. It consists of a Daughtercard that can be used in the PICEL III or a Control Board for a standalone VFO. The Daughtercard uses about 90 ma, and produces a clean squarewave output (~1.5 volts p-p) with none of the spurs associated with a DDS. It provides continuous tuning from 10.000 to 157.000 MHz with 1 Hz resolution. The user interface is provided by two push buttons and a rotary encoder.
The Control Board is 2 x 3.5", and makes a complete standalone VFO with the Daughtercard. It has a two line LCD, two push buttons, and the rotary encoder. A 16F88 is used to control the Si570.
You can use this with a Quadrature Sampling Detector to cover 80 - 10 meters, or as is with a standard mixer to cover 30 - 2 meters.
Click here for a link to AA0ZZ web page for full info on both Daughtercard and control board, along with copies of the documentation.