RF Hacking

Some weeks back, we published our designs for building reproducible TX-BPF filters easily. Designs 10m TX-BPF: Results of the Dhiru's Manhattan build: Results of the PCB build: Why use BPFs? While many amateur radio operators focus solely on antenna optimization, the significant benefits of TX-BPF filters are often overlooked or under-discussed in the hobby! Even with HOA antenna restrictions, you can still optimize your station's performance through proper TX-BPF filtering. ...

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

My homebrewed PA0FRI Active Antenna is working well from a very physically constrained location. Design 3D render: Schematic: Results The antenna is connected to an RSP1 Clone SDR running custom FT8 band-hopping software. I am using a SOLID 4-Way 5-2400 MHz RF splitter to connect multiple SDRs to the same active antenna. NB: Plug in 75-ohm dummy loads (terminators) on the unused splitter ports; MX-282 / MX-280 75-ohm loads work fine. ...

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. Design 3D render: Actual picture: ...