433 MHz CW signal source

Sat, 04 Oct 2025 00:00:00 +0000

For HF and amateur VHF bands our WiFi VFO works great.

But we didn't have a cost-effective UHF signal source until now…

Design

Thanks to Ismo (OH2FTG), we recently experimented with a HopeRF CMT2119A powered board called HOPERF RF module RFM119W-433S1.

Here is the CMT2119A powered board in action producing a CW (OOK) signal at ~433 MHz.

The stability is pretty good and a bit surprising considering that the board uses a 20ppm 26 MHz regular quartz crystal - not bad!