Modern ham radio operators often face restrictions on antennas. This has made small antennas more popular, despite some limitations. [Tech Minds] reviews the GA-450 indoor active HF loop antenna and ...

At present, portable receivers generally use ferrite rod antennas for LF and MF (below 2 MHz), and whip antennas for HF (up to 30 MHz). Each type has proved effective in its particular application.

Using digital techniques has caused a resurgence of interest in VLF — very low frequency — radio. Thanks to software-defined radio, you no longer need huge coils. However, you still need a suitable ...

The purpose of this article is to explain, in detail, the process involved in building and tuning a high-frequency (HF) RFID antenna, which would operate at 13.56 MHz. Some concepts will be explained ...