HF Voyager: an ocean-going drone with a KX3

HF Voyager: an ocean-going drone with a KX3

• https://ae5x.blogspot.co.uk/2018/03/hf-voyager-ocean-going-drone-with-kx3.html
• http://www.jrfarc.org/hf-voyager/
• http://hfvportal.jrfarc.org/

Software-Defined Radios: Products and Math

Software-Defined Radios

https://arachnoid.com/software_defined_radios/

Raspberry Pi: Running an SDR by M0PSX

Raspberry Pi: Running an SDR
By Pete M0PSX29 January 2018

https://www.essexham.co.uk/news/raspberry-pi-as-an-sdr.html

Six meter halo 144 MHz Halo Antenna by Dr. Carol F. Milazzo, KP4MD

 Six meter halo 144 MHz Halo Antenna
Construction and Analysis of a Low Cost Omnidirectional Horizontally Polarized Antenna for 144 MHz
by Dr. Carol F. Milazzo, KP4MD (posted 23 May 2012)

http://www.qsl.net/kp4md/144_mhz_halo.htm

50 Watt HF Amplifier Build By OE1CGS

http://www.oe1cgs.at/50w-hf-verstaerker/

Based on a low-cost kit, the documentation leads step by step over suitable low-pass filters and a custom-made, 3D printable housing to a practical finished device. Overall, with component costs of just under € 50, you can make it and can finish the device in about 6 to 8 working hours, provided that you have a kit, a PCB for low-pass filters, other components and a printed housing.

The main performance data at a glance:

Supply 12 - 14 V DC (max 8 A)
Optimal input power 2 to 2.5 W
Output power 30 to 50 W
Optimized for operation from 40 m to 20 m
Manual band switching
Sufficient suppression of harmonics
Efficiency ≈ 45%
Passive cooling, prepared for fan

Measuring Transmitter Power with the Oscilloscope

Application Note #4
Measuring Transmitter Power with the Oscilloscope
© Roger Stenbock W1RMS 4/19/2012

http://www.dudleylab.com/Appnote-4-Power-tests1.pdf

3_D Printer PCB Jig/Vice

Print a PCB vice with 3-D printer

https://www.thingiverse.com/thing:21357/#files