Lab assessment of impedance mismatch of a UHF/SMA adapter-block

Since I’ve purchased Mini VNA Tiny, my first ever VNA analyzer, I have completely reconsidered all my beliefs around how cables, connectors and how impedance mismatches in general behave around the circuits. The situation, I noticed, is not as ‘innocent’ as it seems. Most recently, amongst many other cables, I have been measuring the loss of a very high quality Hyperflex-10 cable by Messi-Paolini. This is currently the lowest loss…

'Smart' VHF tripod antenna for mobile missions

HF tripod antenna

[DESIGN DIMENSIONS AND MORE PHOTOS TO BE ADDED SHORTLY. MY APOLOGIES FOR THE DELAY, BUT WE ALSO HAVE A FULL TIME JOB TO KEEP OURSELVES GOING…] This article demonstrates the construction of a VHF monopole over a tripod-like ground plane, based on the concept introduced on this post: “Special Tripod Antena…” As stated in previous post this antenna possesses several attractive characteristics:   Only 3 drill holes are required! (one…

Ultra-light super-portable VHF/UHF antenna for critical missions!

This a very simple design of a VHF/UHF antenna for super portable missions! It’s also very quick to construct this antenna, it took me around 30min or so to put all pieces in place. The dipole elements are tunable, the classic adjustable rods used in old FM/AM radios. The blue cables, are copper solid-type core cables. These are used to tight the antenna in rods, etc, wherever you like to…

Experimental construction of vertical VHF and UHF dipole antennas

  More details to be added soon. See a preliminary construction of my vertical dipoles for VHF and UHF transmission and reception: The UHF (top) and the VHF (bottom) vertical dipoles installed on a 40mm diameter PVC waterpipe The top dipole is for the UHF band. The bottom dipole is for the VHF band. Both antennas are fixed on a vertical plastic PVC boom of 40mm in diameter. The dipole…

Prototype tripod ground plane antenna for rapid installation and portability!

┬áThe tripods play the role of the ground for the vertical antenna (short vertical fixed with red tape on a plastic PVC tube) located at the tip . This geometry is not tuned for any frequency, it is presented here for illustration purposes. Vertical and tripod elements are from aluminium. For now, see a preliminary construction of my prototype tripod antenna above. Some of the properties of my design include:…