https://cyberdefensereview.army.mil/CDR-Content/Articles/Article-View/Article/1830071/tactical-employment-considerations-of-hf-radios-in-the-cavalry-squadron/
Tactical Employment Considerations of HF Radios in the Cavalry Squadron The Cyber Defense Review...
There are a few misconceptions about the use of High Frequency (HF) communications in the U.S. Army today, especially in a Decisive Action Training Environment...
https://www.dxzone.com/dx33469/pt40-7-mhz-transceiver-by-aa3sj.html
PT40 7 MHz Transceiver by AA3SJ - Technical Reference/HF Radios | The DXZone
Home made 40 meter transceiver project. The receiver is a Progressive Receiver with a few modifications. The Transmitter is a modified MFJ Cub circuit....
https://ham-radio-antenna.net/type_c_charging_ga_800_active_loop_shortwave_10khz_159mhz_hf_radios_antenna_4acc4.htm
TYPE-C Charging GA-800 Active Loop Shortwave 10KHz-159MHz HF Radios Antenna