An antenna for 7MHz local contacts
- This article describes the design of an antenna for local contacts on 7MHz, including a simple and efficient matching system that presents a 50 ohm load to the transceiver.
144 Mhz power amplifier 4CX250B
- This page provides information on the design and practical implementation of a rather inexpensive 144 MHz high power amplifier using a pair of ceramic tetrodes type 4CX250B by LA0BY
Interdigital bandpass filter designer
- Fill out the form to design a bandpass filter as described in the January 1985 issue of Ham Radio Magazine. These filters are generally limited to frequencies above 200 MHZ because their size is slightly longer than 1/4 wavelength