5/8wave workman swr issues? Balun? Unun?

[Marconi]

BM, I guess you're asking me.

Same feed point height.

The Gain Master is higher by about 6' feet. I placed these two with the centers as close to the same height as I could determine in order that the current maximums were the same.

 

[BOOTY MONSTER]

thanks

 

[northern35s]

IMO, the GM is a center fed 5/8 wave radiator, and the technical indications shows an improved free space pattern over a standard 5/8 wave ground plane. That is the advertised gain advantage.

Like you suggest, in my operations here in Houston I don't see a real benefit with my GM over my Starduster at almost the same height, locally or with DX. I've been comparing them over a year now, but for me all my antennas perform about the same and guys don't like to hear that.

I thought you were doing your radio work like field day work, and thus out of convenience your install was pretty low. How high is your mount?

If you live right on the water and you want to see some real improvement in DX performance, then install a real beam h o r i z o n t a l.

Aluminum takes a real beating that close to salt water and so would a rotor, but that would be my suggestion. Maybe a quad design with some good copper wire that doesn't stretch much, fiberglass and stainless parts would hold up better, but then you have wind to deal with too.

Good luck,

I believe the GM shows improved gain at 0degrees in free space, 0degrees over ground won't happen, any radition at 0degrees is cancelled by ground reflection in the fresnel zone! That said you're in business at any angle greater than this.

As for the horizontal beam over water, it is bound by the same rules that apply over real ground, height, for a beam to have a low take off angle it has to be high relative to its wavelength, this is why the vertical is such a good performer by the sea and the default choice for island DXpeditions

 

[Marconi]

I believe the GM shows improved gain at 0degrees in free space, 0degrees over ground won't happen, any radition at 0degrees is cancelled by ground reflection in the fresnel zone! That said you're in business at any angle greater than this.

As for the horizontal beam over water, it is bound by the same rules that apply over real ground, height, for a beam to have a low take off angle it has to be high relative to its wavelength, this is why the vertical is such a good performer by the sea and the default choice for island DXpeditions

Yes, I think you are correct.

I was just thinking of raw gain from a multi-element beam vs. him trying to make a vertical beam with his current vertical antenna, by adding a reflector in back of it somewhere.

 

[ghutch]

This antenna has been used at the national seashore....south of town. I set up on the beach, next time I go down to the land cut its going to be set up there. My height during tests is 10 ft of metal mast, I could raise as high as 20 ft just needs another top rail tube....that would be max. I want to try the antenna at 4-5 feet above sea level. Mount it on a dock over the ICW waterway? Just to see how it do. the mast could be set down into the saltwater. water is about 5 feet right off the dock. this leaves the radials at 4-5 feet above the warterand could raise to 10 feet at the same spot. Using the 20 feet of mast puts me on the sand as this would be a problem mounted to the dock.
A hor. Beam is to large and complex to set up and tune....thus the vertical.
I was looking at a website that used 1/2 wave vertical, center fed with a reflector right at the surf, thought I have two of the 5/8 might be worth a try??
I have read the topics related to the gain master I thought it was such a center fed dipole.
You are 100% right on the saltwater and aluminum not mixing well....I had this antenna down the beach just a few times and the galvanic corrosion wind etc has taken it toll! The has couple times it has tuned to 1.25 or slightly above swr at the marks I placed on all the tubing so setting up is fairly easy. The clamps have had to be replaced and the joints all need a good cleaning before the tubes are assembled .....saltwater is battery acid!! I need to post some pics but the files are too large....I need to get them reduced down.