Inactive Projects


SDR Documentation

Dual 9954 Board


Si570 Board


A 1" by 1.35" circuit board has been designed for the Si570 programmable crystal oscillator chip. The board contains the Si570, a 3.3V regulator, a bidrectional level shifter for the I2C inputs, an optional droppoing resister(for 12V use),sma outputs, and headers for I2C control, power input, VCXO control(used on Si571 only),

The first kits started shipping on Nov 20. The 2nd 200 boards are on order and expected Monday, Nov. 26.

Tom, KM5H of the Softrock40 Yahoo group is doing a large group buy of the Si570. My parts kit does NOT include the Si570.

The group buy for the Si570 Chips is here

The parts kits contain the following:

2 - 10uF; 3 - .1uF; 3 - .01uF; 1 - 200K; 2 - 49.9; 4 - 1K; 1 - GTL2002; 1 - LP2992AIM-3.3V


12V to 24V Convertor



Projects I have started in the past but are not currently working on include:

Software Defined Radio:

The Software Defined Radio consists of 5 boards making up a complete low power USB controlled transceiver. Each board is 1.5" by 3.5".

High Speed USB Controller:

The High Speed USB Controller board contains a Cypress CY7C68013A high(480Mbps) USB controller with an embedded 8051 type processor. All I/O lines are brough out to connectors. Prototypes have been built, assembled and tested. This board design is being ported over to KICAD andwill be produced and offered for sale.

AD9958/9 DDS Board:

The AD9958/9 board contains an AD9958 or AD9959 DDS with 2(9958) or 4(9959) independent outputs. Each output has a low pass filter. Both analog and squarewave outputs are provided for each channel. The board also contains a 125 MHz oscillator and local voltage regulators. One prototype has been built and tested. The analog outputs work correctly. The squarewave outputs exhibit crosstalk in the comparators if the 2channels in each comparators are not on the same channel. This appears to be a layout problem and will require a small change in the layout.

QSD/QSE Board:

The QSD/QSE board contains a quad sampling detector and a quad sampling exciter. These are similar in design to those in Youngbloods design in the series of articles "Software Radio for the Masses" and to the Softrock series. Prototype boards have been produced but not assembled.

BPF(Band Pass Filter) Board:

The Band Pass Filter Board contains 6 seven section Chebychev band pass filters and 2 FST3251 8 channel analog multiplexers. Theboard is currently in its second production run. Details and PayPal buttons can be found in the "Boards for Sale" section.

D/A - A/D Board

The D/A - A/D Board contains a PCM1793 24 bit D/A and a PCM1804 24 bit A/D. Board prototypes have been made but not assembled.

Dual AD9954 IQ DDS:
A prototype board for an IQ generator using 2 AD9954(also work for 9951-9953)
DDS's has been designed and produced. I have not populated or checked out a board