I was aware of RFzero for quite some time and missed out on the first batch, then due to the IC shortage production was put on hold for awhile until now. Bo (OZ2M) recently posted on the 8M IO group that he had units ready to go, so I jumped at the chance of purchasing one. He made transaction a breeze and it arrived quicker than I thought.
The RFzero™ is an Arduino multi-purpose GPS controlled Si5351A RF unit. It can be used as a beacon (IBP, SPB, CW, FST4, FST4W, FT4, FT8, JS8, JT9, ModeX (JT65, Q65, …), PI4, WSPR, …), stand alone WSPR/FST4W transmitter, signal generator, VFO, QO-100 dual LO, low cost GPSDO. If you've never heard of it before click here to find out more.
The board is pretty much ready to go except soldering 4 LED's and the RFzero manager software makes its easy to change the parameters if needed.
As I had experimented with 40MHz band (under ISM) before using my FT-817ND and attenuating my output to a massive 10mW ERP I was impressed when carrying out remote site tests under normal conditions I could detect WSPR transmissions quite a distance from my QTH. The best remote site test was over 12 miles away just using a homemade halo in the loft for transmit and a loop for a receive antenna.
I wanted to apply for the T&I licence but didn't want to tie up my FT-817 for a WSPR or FT8 beacon so my plan is to now use the RFzero as the heart of a FT8/CW beacon on the 8M band. I have order a GPS antenna and now starting to look for a suitable amplifier to take the 20mW to a reasonable level like 5-10watts. I have approached EX8MLE who designs very good amplifiers but from what I can see on his Youtube videos the amplifiers for 40MHz - 70MHz are 25watt - 50watt output.
So if anyone knows of a suitable 5-10watt version please let me know.
