Amateur Radio Blog
Upon request, I build 1:1 baluns (aka common mode chokes) for other amateur radio operators. I often receive questions about the maximum power at which the balun can be used. In response, I provide the maximum load for use in SSB mode. I do this for a reason, as there Continue reading Understanding PEP power and Duty Cycle in amateur radio
For more than eight years I have been battling manmade noise, or QRM. In this, I am not alone. The entire ham radio world is experiencing a rapid increase in manmade noise. The result of the many electrical devices used in the home. From phone chargers to LED lights and Continue reading Using AI to eliminate noise in a radio signal
Past few years I have been building common mode chokes, 1:1 baluns aka 1:1 ununs on request. One of the questions asked by fellow hams is where to install it, which depends on the type of antenna. Then the ‘counterpoise’ enters the story and why certain antennas need one. So Continue reading Why does an antenna require a counterpoise?
The space available for an HF antenna at my location is very limited. The plot where I live is only 5 meters wide. If you want an HF antenna that covers the 20, 17, 15, 12, and 10-meter bands, you quickly end up with an antenna like a Cobweb. I Continue reading Review of the 7-band AWK Cobweb antenna
It seems like some kind of magic object, the 1:1 balun. Some say it can solve many antenna problems. It could turn a bad SWR into a good SWR. Increase antenne bandwith. Reduce interference in reception. Prevent RFI that causes interference to electrical devices at your neighbors and your own Continue reading Why does an antenna need a 1:1 balun?
You often hear about it and it is a hot topic on forums, repeaters and club gatherings. I have interference (RFI) on my equipment or that of my neighbors caused by my own radio signal. What can I do about it? First of all, the best strategy is to tackle Continue reading How to prevent RFI caused by EndFed, vertical and dipole antennas
Because of the very limited space for antenna placement, 20m2 at most, I have experimented a lot with different antennas for transmitting and receiving over the past few years. Most important for me is the performance on the 10 meter to 20 meter band. For those bands, I have now Continue reading The Cobweb vs Rybakov vertical antenna part 1
It has been around for a long time, but is only used on a small scale in the ham radio world; diversity reception. This is a pity, because diversity reception not only offers the possibility to reduce QSB (fading). With diversity you can also eliminate QRM (manmade noise) very effectively. Continue reading Getting rid of QRM with diversity receive mode
In the world of amateur radio, the terms balun, unun, common mode choke, line isolator and impedance transformer are often used. But also often mixed up and sometimes lead to heated discussions on forums and social media groups. For your convenience (you don’t have to ask on a forum or Continue reading The difference between a balun, unun, common mode choke, line isolator and impedance transformer
When I worked with the Cobweb antenna for a while, I started to miss working the lower bands, 30 to 80 meters. Now it’s not easy having all your antennas on only only 20m2 of space on te roof. I can’t fit an EndFed, G5RV or a Windom. I can Continue reading The surprisingly well performing Rybakov HF vertical
If there is one antenna that has grown considerably in popularity in recent years, it is the Cobweb antenna. The Cobweb is so popular because of various reasons, like its small size, only 2.8 x 2.8 m for a version with the 20 meter band, as its longest wavelength. In Continue reading Cobweb antenna pros and cons
It’s been a while since I posted again, but then I have something to report. Last year, I started experimenting with variants of a horizontal polarized omnidirectional antenna. The Cobweb, the Cobwebb and the Classic Halo. I can now tell, from my own personal experiences, which of these variants could Continue reading Multiband Cobweb(b) vs Classic Halo; final verdict