Very simple software for PLL ADF4351 and ATTiny13 can be compiled with arduino and microcore https://github.com/MCUdude/MicroCore
v 0.2 Ondra OK1CDJ 5/2020 ondra@ok1cdj.com
ADF4351 eval board from eBay or Ali for aprox. 17 USD.
Please check the ADF4351 datasheet or use ADF4351 software to get proper PLL register values.
Simple CW beacon. SW is also for ATTiny13 now or can use ATTINY45/85 on same PCB. Beacon send string in morse code like - OK1CDJ JO70VA and then continous tone for 5s.
Version with external keying on PB0 of ATTiny13. Can be used as simple CW transmitter.
MCU is powered by 3.3V directly from PLL board.
pin 5 - PB0 external keying - optional
pin 3 - PB4 to ADF4531 clock (CLK)
pin 2 - PB3 to ADF4531 data (DATA)
pin 7 - PB2 to ADF4531 latch enable (LE)
Kit is available here:
https://www.hamshop.cz/pll-adf4351-c51/adf4351-ovladani-s-attiny13-stavebnice-i351/