This kit is a simple minimalist controller for the Si5351A Synth kit (included with the ProgRock kit). It is intended as a programmable crystal replacement. It has three independent outputs with frequency range 3.5kHz to approx 300MHz, and can be optionally GPS disciplined.

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The features of this kit are as follows:

  • Includes Si5351A Synth kit AND "ProgRock" PCB kit
  • Easy construction, no surface-mount components to solder (Si5351A already pre-soldered)
  • 3 independent 3.3V p-p squarewave outputs (2 if you use GPS discipline)
  • You can feed the outputs through LPF kits to get sinewave outputs
  • 8 selectable “banks” of frequencies, chosen by 3 input control signals
  • Frequency range 3.5kHz to 200MHz
  • Extended frequency range up to approx. 300MHz if you don’t mind violating the Si5351A datasheet specifications
  • GPS frequency discipline using 1pps from a GPS receiver
  • Unique power supply noise filter circuit designed by Alan Gray G8LCO
  • Power supply voltage 5V, or using LM317LZ regulator (supplied), range is 5-12V DC
  • Minimalist configuration user interface using 4-way DIP switch, push button, and LED
  • Optional serial port configuration (requires firmware pr1.01 and above)
  • Frequencies and configuration stored in non-volatilte memory (EEPROM) for next power-up

Documents and resources

Assembly instructions ProgRock kit: A4 format or Letter format
Operating manuals pr1.01a firmware Operating Manual: A4 format or Letter format
pr1.01 firmware Operating Manual: A4 format or Letter format
pr1.00 firmware Operating Manual: A4 format or Letter format
Si5351A Synth kit manual Si5351A Assembly: download here!


Version history

Version Date Features
pr1.01a 22.Mar.2017 - Bug fix to pr1.01, there was an initialisation problem so it started up at 27MHz output
pr1.01 06.Mar.2017 - Added serial interface configuration option
- Changed Si5351A Code to all integer arithmetic - faster, smaller, more accurate
- In DIP switch configuration, LED flashes 4 times to indicate a button press is registered
pr1.00 20.Apr.2016 - Original kit firmware version


Kit photographs