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On this page you can listen to and control a short-wave receiver located at the amateur radio club ETGD at the University of Twente. In contrast to other web-controlled receivers, this receiver can be tuned by multiple users simultaneously, thanks to the use of Software-Defined Radio. Provided by PI4THT

The K9GDT 40m receiver

Sharing beverage antennas with this switch boxes is possible. This article describes a 6-position remote antenna switch for Beverage antennas on 3 bands (160m, 80m, 40m). It allows selecting one of 6 antennas for each band without affecting other receivers. The system uses a control box with a rotary switch and a separate splitting box with bandpass filters for each band.

Practical and usable direct conversion receiver for the 40 m CW band

Raspberry Pi WebSDR Receiver Project running SoftRock Lite ii Receiver (40m) and Raspberry Pi Model B

The Rock-Mite is a 40m CW kit offered by Small Wonder Labs . It features built-in keyer, direct conversion receiver with a crystal RF bandpass filter, 500 milliwatts of power, and switchable frequency offsets to work around QRM

Homemade LC Bandpass Filters for 20M, 30M, 40M In multi-station environments like special events, field day, portable operating, is very important to protect receivers from excessively strong signals. Bandpass filters help to protect your transceivers.

The purpose of this webpage is to document an attempt at this project starting with the 80m core receiver first and also having the parts on hand for then adding the first dual conversion band (40m)

Since 2011, crkits offer radio kits that you cannot find on eBay or AliExpress. Includes HT-1A 20/40m Dual Band CW Transceiver Kit, D4D DSB Transceiver Kit for Digital Mode, R3500D ARDF Receiver, CW Transceiver Kit

Listen to online WebSDR located in Andorra Europe. Four receivers on 60m, 20m, 40m, and 80m, connected to a dipole antenna direction East/West

This study compares the reception performance of vertical and horizontal loop antennas on HF bands in a densely populated area. Using identical Wellgood active loop antennas and receivers, the experiment monitored FT8 signals over 24 hours. Vertical loops outperformed horizontal loops on higher bands (10m, 15m, 20m), while horizontal loops excelled on lower bands (30m, 40m, 160m), particularly in receiving long-distance (DX) signals. The horizontal loop's advantage on lower bands may be due to better low-angle performance and reduced sensitivity to man-made noise. Further research is needed to fully understand these differences and optimize antenna placement for various HF applications.