433 MHz CW signal source

For HF and amateur VHF bands our WiFi VFO works great. But we didn't have a cost-effective UHF signal source until now… 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! ...

October 4, 2025 · 8 min · 1624 words · Dhiru Kholia

WiFi VFO, beacon and signal generator

We make heavy use of https://github.com/kholia/Easy-Digital-Beacons-v1 for testing RF amplifiers. This single board is a versatile WiFi VFO and FT8 / FT4 / WSPR beacon. You can also use our CW-SigGen project to generate a suitable test signal.

July 5, 2025 · 1 min · 38 words · Dhiru Kholia