Αποτελέσματα Αναζήτησης
22 Νοε 2023 · Antenna Grounding Planes. Part of omnidirectional cellular antenna design is a ground plane - or metal that reflects signal into the antenna itself. Many antennas have a ground plane built in, but in particular magnetic mounted antennas (often kitted with mobile vehicle boosters) require one be provided.
A ground plane antenna for 2m or 70cm is one of the simplest antennas to build and get working, and it can work quite well for repeater or simplex operation. It is easy to build for other bands as well. I’ll show you several different construction methods that you can use, based on the materials you have available.
The antenna designs presented here are specifically cut to the dimensions necessary f or proper operation in 140 -150 MHz VHF band. Each chapter deals with a particular design and an extra chapter at the last part is added to help the constructor in converting the given antenna dimensions for other frequencies.
The J-Pole antenna became so popular in the VHF band because of its simplicity in design and construction. The MARS’..ians mass produced this antenna during the VHF frenzy in the mid-80’s. It is a vertically polarized half-wavelength radiator and fed with a quarter-wave stub to shock excite it.
3 Ιαν 2010 · I built a VHF antenna that I find works well on upper VHF (7-13) at least, out to pretty decent distances. It also works respectably on low VHF at decent distances if placed outdoors away from noise sources (as any low-VHF antenna would need to be).
Build this simple VHF/UHF bidirectional antenna from readily available. materials. John Stanley, K4ERO. in The ARRL Antenna Book.1 It provides useful gain with very simple construction. The hourglass form factor yields an antenna that is tall but with a tiny footprint and that doesn’t look li.
This page contains construction details on a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use. Since an old 5 element version (v1) of my antenna was shown in the July 2011 edition of RadCom, a few people have contacted me asking for some information on how it was constructed.
