I recently spotted the Tokmas CI7N170SM TO-247 part on LCSC. It seems like a pretty neat part for building non-QRP HF amplifiers! This could be a better part for our Baby QRO amplifier. Datasheet excerpts: The full datasheet is available here. In comparison, here is how a professional RF part (MRF300AN) looks like: That 272W maximum power dissipation figure is crazy good but switching characteristics are not that great (fast).
Tokmas CID9N65E3 rocks! It is CRAZY how efficient this GaN FET is in TO-252 (DPAK) package. It generates 5W @ 28 MHz with 13.8V at drain without even warming up! Close to 4W @ 50 MHz with 12.0V at drain. 5W+ @ 50 MHz with 13.8V at drain. 11W+ @ 50 MHz with 20V at drain. It even produces ~3W at 70 MHz with 13V at drain - w00t! ...
I recently found some FET gate drivers which are quite fast! Wuxi Maxinmicro MX1025D - Favorite! BD2311NVX-LBE2 from ROHM Semiconductor TI LMG1020 Tokmas LMG1020YFFR - https://www.lcsc.com/product-detail/C6423790.html They are perfect for driving the fast Tokmas GaN FETs that we recently discussed on this site. Our 'workhorse' gate driver for the recent experiments has been the Onsemi's NCP81074ADR2G in a friendly SOIC-8 package. And we have shifted to MX1025D gate driver in our latest amplifier designs. ...
This ~1W to ~5W WSPR beacon runs continuously on the 10m band. It handles extreme environmental temperatures pretty well (it is 42°C plus here). Our article on this beacon's design and operation will appear in the May/June 2025 issue of the QEX magazine soon. References: http://www.carnut.info/WSPR_Tx/WSPR_Tx.htm QEX May-June 2025 TOC QEX May-June 2025 Perspectives ...
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. ...
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! ...
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: ...