Practical Guanella 1:1 balun
- This article proposes a lossy transmission line model of a practical Guanella 1:1 balun that is effective for all frequencies within and immediately adjacent to the pass band
- Have you ever wondered where different modes should be operated, what frequencies to avoid as a courtesy like SSTV etc? This site offer a database for known net frequencies,known segments for different modes, known beacons
Frequencies for using digital modes
- These frequencies are to be used as a guide to find the related signals. They have come from several sources, and are, in no way, guaranteed to be complete, accurate, or inclusive.
Olivia, the Magic Digital Mode
- Olivia MFSK digital communications are becoming popular in amateur radio because Olivia is one of the most robust methods of text keyboarding, that can perform superbly for long distance communications. Olivia frequencies, format and software
- Filtroid is an extremely easy-to-use program for synthesizing microwave filters. It can be used to design practically all filter types from audio to microwave frequencies as well as amplitude and delay equalizers and attenuators.
Inductor Design Software - RF toroid
- A free too designed to assist in the selection of iron and alloy powder cores.
RF toroid calculate the location of the Self resonate frequencies for series and shunt inductors.
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