GRV5?

This antenna design is a winner. One of the best antennas I ever used was a 270 foot delta loop with the apex at about fifty feet. I had a run of 450 ladder line to a 4:1 just outside a window, to a short run of coax into a tuner. Worked great!

 

Basically the 5RV is nothing more than a dipole which is normally quite respected. The point being that if you operate 2 opposed bits of wire at half wave resonance you get a nice resistive 70 ohms but move away from resonance (like a different band) then you get wierd and wonderful input impedance. If you then measure that impedance a fraction of a wavelength away at the end of a length of twin feeder then you get totally another impedance. By picking the exact length of dipole wire, the length of twin line and impedance of the twin line (this of the trick of the 5RV) then you can arrange it that the weired and wonderful impedances on the bands of interest were not that far from an acceptable match that the o/p stage of a valve rig managed to feed it ok. I use a half size 5rv & am quite happy with it. I know of one amateur who had the clone standard FT757GX2, pump up mast and 3 ele tribander who was very upset when his friend along the road got a much better signal from some tasty DX with his TS820 & a full size 5RV tied from his house to a big tree in a field (I am not saying a 5RV is a better aerial than a tribander but given the right conditions it can certainly hold its own) .

2 things that can kill a 5rv... not using a balun & not keeping the feedline normal to the dipole part (it does not have to be vertical.. mine comes off horizontally to an upper widow). If you are not valve you will need an atu.

The difference in performance between a $50 aerial and a $500 one can be surprisingly little

 

I just setup my G5RV this afternoon and I'm getting great results. Due to space limitations on my property, I had to set it up as an inverted "v" but to make things more complicated, the top of the "v" is not directly overhead but on an angle. I basically have the top on my roof mounted on an 8' piece of PVC then both legs run out to their 51' lengths and the ends are tied off to different corners of my property. The corners are 82' apart so you can see that the "v" was my only real option. So far, I've gotten California and France via PSK31 and Indiana for voice.
My other antenna is a Titan-DX which works great, but I wanted to try a wire to see the difference. The G5RV seems to pull out the signals a little bit stronger.

Jim
WA3ERQ

 

I love the differences in our use of the english language. What you call valves we call vacuum tubes or tubes. As I always say a lift in England will get you to the next floor but a lift in the US can get you to the next town.

 

A good write up was posted on the G5RV this morning at eHam..

http://www.eham.net/articles/21682

 

re:

yes, the good old g5rv. initially a monoband antenna, being 3 half waves on 20m. really, if you truly want multiband operation from this antenna then do yourself a favour, and feed the antenna with balanced line, all the way from your antenna tuner. your losses will be negligible, compared to using the balanced line/coax combo.
there will always be at least one, maybe two bands that will be difficult to tune with the original coax/bal line combo, and the performance will be mediocre at best. using bal line all the way,your antenna will perform very well. as an other poster suggests, you can also use parallel coax lines, as an alternative, if rf in the shack is a problem.
or just go with a carolina windom. this gives an acceptable match using coax feed.
good luck de bob. ve3ptc/gmoley

 

Is a GRV5 better than a G5RV? How does it compare to the GV5R?

 

G5RV Tips

Have been using a G5RV for sometime now because of the great results I get with it both on Transmit & Receive, I use mine mostly on 75 meters so I have tuned my antenna so I have a low SWR there 1.2 to 1.5 from 3800 to 4000 don't need the tuner for 75 but do need it for 40-10 where the where SWR is around 3 to 1 most places. To tune a G5RV for a band like 75 or 40 start with a 100ft piece of RG8X and temporally tie it to the 33' matching stub on the G5RV and take SWR reading, then trim off a little coax, and take more reading till you et what your looking for in my case 75' worked great for 75 meters and 70' worked well for 40meters..............kb6hrt