My sketch for an Arduino and si5351 to implement a VFO, BFO, CW, keyer, and control lines is here. Make sure you look at first. I have used it for at least a dozen homebrew transceivers and transmitters over the past four years (including all of my Summit Prowler SOTA QRP portable rigs), with constant refinement.

VFOs around the World

David VK3KR is using the script to run this finely made VFO BFO Controller module in a compact portable all homebrew SSB and CW transceiver for 160 to 20m. The VFO board was designed and fabricated (JLPCB) by Glenn VK3PE. David is planning to include a W6JL 50 watt amplifier module — making for a very nice transceiver for Parks and SOTA activations.
Robert SP3RAF from Poznan in Poland is using the script to develop a compact holiday SSB and CW radio for 80, 40, 30 and 20m, with ADE-1 mixers, dual gate MOSFET IF amplifiers (BF1012), and a push pull RD16HHF1 FET PA. Pictures to follow.
Jerry W0PWE used some of my code to develop this 40m CW QRP mobile transceiver, which he operates while driving the East Coast USA highways!
Heinz VK4YI built this beautiful multiband transceiver based on the OzQRP MST design, with my script.

Mladen 9A3XZ tried out my script in a ‘al fresco EI9GQ transceiver…

Adrian M1LCR was looking to use my script to update his excellent 8-band G6LBQ transceiver. He is also building an EI9GQ transceiver in the style of the wartime clandestine brief case radio.
Hubert F6DUK used my sketch in his finely made 60m monobander, based on he VK2DOB OzQRP MST design.
Hubert F6DUK’s VFO assembly.
Lorenzo I3ZYJ showed me his Arduino si5351 VFO as a crystal bank replacement in an older 2m FM transceiver.

Colin VK2JCC’s first homebrew SSB rig is using my sketch.

Steve G4ALG is using my code in his external VFO to control his lovely vintage Yaesu FR-50 and FL-50B receiver transmitter pair.

Further details of Steve’s project here.

Piotr SP9LVZ contacted me and showed me his first successful attempt at getting the VFO Controller up and running with an OLED. Piotr then sent me updates and pictures over a 3 month period as his excellent multiband CW transceiver came together. This is a fantastic build and shows attention to design, physical, electronic and RF details that have payed off in the form of a handsome homebrew QRP CW transceiver.

In early May 2023, Piotr writes “Hello, I have completed the assembly of my QRP CW transceiver. Everything works fine! Today I participated in the national QRP contest and I made 31 QSOs. Final photos before closing the case. Thank you for all your help.
VY73! Piotr SP9LVZ”
. Well done Piotr!

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