Using inner conductor of a coax feedline as an antenna
网页2015年12月18日 · The inner conductor is shielded by the outer. I you want to use coax as an antenna, then it's easier to use the outer conductor. Given a ground plane the outer conductor of coax measured to 1/4 wavelength of the frequency can make a good transmitting antenna. Share.
coaxial cable - Using 75 Ω instead of 50 Ω coax feed - Amateur …
网页2019年6月23日 · 7. Sure, you can use 75 ohm coax instead of 50 ohm. In some cases (such as feeding a dipole), 75 ohm coax may be a better match to the load than 50 ohm. In other cases (such as feeding a vertical), it may be a worse match. You may not even need to do additional matching.
Using cable coax rg 11 - Amateur Radio Stack Exchange
网页2016年5月20日 · 1. Yes, RG-11 coax can be used as a receiving antenna wire by attaching the braid outer conductor to the antenna connection post on your receiver. You ignore the inner conductor as it serves no useful purpose in this application.
Which cable is better for ham radio antenna? RG58, RG59, or RG6?
网页2020年8月2日 · This is especially true for RG-59 and RG-6, which are aimed at nontechnical consumers wanting to put CATV cabling in their home. Besides loss, coax has a characteristic impedance. Most coax is either 50 ohms or 75 ohms. RG-58 is 50 ohms, RG-59 and RG-6 are 75 ohms. CATV and video applications conventionally use 75 ohm.
antenna system - Need advice for running coax for HF to my shack ...
网页Run a new proper 50ohm coax line to the shack using the easiest route that I can find (~130 feet of cable inside the house). I'm confident I can do this successfully. My only concern is the length of cable required (~130 feet inside + ~150 feet outside to the antenna = 280 total feet). It would be possible to create a shorter path by drilling a ...
Connecting a coaxial cable as feed to a halfwave dipole
网页2018年6月15日 · With an unbalanced antenna system using coaxial cable, there are three currents: (1) center conductor current; (2) inside of outer conductor; (3) outside of outer conductor. The difference in currents (2) and (3) is due to the skin affect that allows them to be considered as separate currents. It is that outer current in an unbalanced system ...
Coax cable as antenna for 5 watt handy - Amateur Radio Stack …
网页2018年2月19日 · 2. If you want an antenna at the end of a length of coax, in my experience, simply stripping the last 1/4 wave of coax and leaving the inner exposed, does not work. The VSWR is high and unstable, as the other half of the dipole is completely undefined. What works a lot better is to carefully extract the inner from the braid, or re-attach the ...
Can I feed multiple different band antennas with one coax?
网页2022年10月6日 · The idea is that a center-fed dipole antenna that readily accepts 20m signals will eagerly reject 10m signals! (Since the frequencies are approximately double, the 20m quarter wave element with an impedance not terribly far from 50Ω looks like an end-fed half wave element to a 10m signal — an impedance perhaps more in the 500–5000Ω range!)
rfi - Do chokes at the antenna feedpoint stop the coax from …
网页2020年7月14日 · For transmit, the choke's purpose is to reduce external coupling between the antenna and the coax when the antenna needs to be balanced and the coax geometry might disturb this. The ideal location for the choke in this situation is at the antenna feedpoint where it is suppose to be balanced.
VNA basics, antenna coax cable - Amateur Radio Stack Exchange
网页2022年4月21日 · When I attach the antenna directly to the VNA I get results that seem to match the antenna specs. Optimum frequency is around 150MHz, SWR close to 1. When I connect a length of coax cable (<1m) between the VNA and antenna everything shifts down to …