New RF parts and new promises

Ismo (OH2FTG) recently introduced me to a bunch of Tokmas RF parts. Out of these, the Tokmas CID10N65F GaN FET stood out. It seems to have a lot of potential (for HF + 6m) at a very low price point. This RF MOSFET part can be purchased from LCSC. It seems Tokmas CID10N65F has the potential to completely replace the RD16HHF1 part from Mitsubishi Electric! Datasheet excerpt: The full datasheet is available here. ...

March 20, 2025 · 2 min · 241 words · Dhiru Kholia

1W WSPR beacon @ 5V (2025)

I have designed, built and tested an all-HF WSPR beacon which produces 1W @ 5V and is rugged and cost-effective. Power consumption: Around 420mA @ 5V. Cost: Around 500 INR. Time to build: Less than 30 minutes. The files for this project are published here for personal (non-commercial) usage. For a 5W (QRO) WSPR beacon, please hold on for our upcoming QEX magazine article ;) Special shoutout goes to Brad (K1TE) for always pushing me to do better - thank you! ...

March 14, 2025 · 1 min · 125 words · Dhiru Kholia

100mW WSPR beacon (2025)

I have built probably the easiest, reasonably rugged and most cost-effective 100mW WSPR (or FT8) beacon. Here is my quick and dirty build with whatever I had lying around: We have replaced the traditional expensive Mini-Circuits transformer with a cost-effective Bourns coupled inductor. Power consumption: Before RF generation starts -> 20mA @ 5v. After RF generation starts -> 52mA @ 5v. So the power input consumed in the RF generation process is more than 150mW it seems (which is good). ...

February 14, 2025 · 1 min · 166 words · Dhiru Kholia

250mW WSPR beacon (2025)

I am building an easy-to-use and cost-effective WSPR pHAT for Raspberry Pi Zero 2 W. 3D render: We have replaced the traditional expensive Mini-Circuits transformer with a cost-effective Bourns coupled inductor. Results: To be built and tested soon! Time to build: Less than 20 minutes

February 9, 2025 · 1 min · 45 words · Dhiru Kholia

Baby-QRO RF switching amplifier

Sometimes we all need a bit of QRO - Life's too short for QRP sometimes. So we give you the Baby-QRO switching amplifier! This Baby-QRO switching RF amplifier design is inspired by the wonderful Single NXP MRF-101 Eval Board project by Jim Veatch. Thank you Jim! Instead of using the expensive MRF101 MOSFET, we use fast SiC MOSFET(s) from Wolfspeed / SUPSiC. 3D render: Actual picture: ...

January 31, 2025 · 2 min · 233 words · Dhiru Kholia