Which is better? Gama fed or direct fed like the V58? Any advantages one over the other? Will one hear better?
Thanx
Thanx
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Ground Plane? Gama Fed or Direct Fed?
- Thread starter Charlie Brown
- Start date
I don't think we're able to tell any difference without some very high tech measuring device.
Cool thanx man. I bought a home brew full wave GP it has a gama on it. Gonna give her a try. Thanx again.
B
BOOTY MONSTER
Guest
a full wavelength is gonna have a very high TOA because the vertical is too long . it should be a simple matter to shorten it to 22 1/2 to 23 ft though . how long are the ground plane elements ?
B
BOOTY MONSTER
Guest
if it's 9 ft it's a 1/4 wave ground plane . they definitely work and some sometimes they're the best antenna for a particular location .
or were you saying just the ground elements are 9 ft ? i had better performance with full 9 ft ground elements than i did with more shorter ones so im a fanboy of them
or were you saying just the ground elements are 9 ft ? i had better performance with full 9 ft ground elements than i did with more shorter ones so im a fanboy of them
B
BOOTY MONSTER
Guest
can you measure the vertical ? it doesn't look 4 times longer than the ground elements in the pic to me , looks to be a 5/8 or .64 ..... nice looking antenna to . the wolf .64 uses a gamma and its a 5/8 also , albeit , it uses two separate loops along the vertical and a top hat . should do pretty well for ya 
can you post any close pics of it to show how its constructed . some folks here like to homebrew and theres no shame in borrowing anothers construction ideas
can you post any close pics of it to show how its constructed . some folks here like to homebrew and theres no shame in borrowing anothers construction ideas
can you measure the vertical ? it doesn't look 4 times longer than the ground elements in the pic to me , looks to be a 5/8 or .64 ..... nice looking antenna to . the wolf .64 uses a gamma and its a 5/8 also , albeit , it uses two separate loops along the vertical and a top hat . should do pretty well for ya
can you post any close pics of it to show how its constructed . some folks here like to homebrew and theres no shame in borrowing anothers construction ideas
A gamma match is used to -raise- the feed point impedance -TO- 50 ohms. A direct feed of your antenna would mean feeding a less than 50 ohm input with a 50 ohm feed line, not so good.
- 'Doc
(It can't be a full wave length antenna, it's a 5/8 wave (or /64 if you like). A full wave antenna that's end fed will have an input impedance of something between 1000 and 2000 ohms and that gamma match wouldn't even touch that.)
- 'Doc
(It can't be a full wave length antenna, it's a 5/8 wave (or /64 if you like). A full wave antenna that's end fed will have an input impedance of something between 1000 and 2000 ohms and that gamma match wouldn't even touch that.)
Was that made by wild bill? I have talked to Harley rider and could hear him from Nashville at 125 miles. He was running some power but I thought it was great still. I talked to wild bill on his oversized quad and all I can say is that night it was working great/
Have you measured its bandwidth?
This is probably one of the ricketiest (?) antennas I've knocked together, but I wanted to try it before it was dismantled for use of parts on something else. It has the Maco V58 style tapped tuning ring on it.
I've got it 30' up next to the house. It seems to work well hearing as good as any I've put up in its class. Everything is DX right now, so that isn't saying too much.
As for some SWR bandwidth info, the MFJ-209 reads it like this from the end of the coax in the shack:
2.1:1 --------------- 29.080
1.5:1 --------------- 28.515
1.2:1 --------------- 28.095 (lowest reading without further tuning)
1.3:1 --------------- 27.555
1.4:1 --------------- 27.385
1.5:1 --------------- 27.050
2.1:1 --------------- 26.295
More length and tap point fine tuning would likely get it a little different, but it isn't too bad for a pile of spare parts thrown together.
This is probably one of the ricketiest (?) antennas I've knocked together, but I wanted to try it before it was dismantled for use of parts on something else. It has the Maco V58 style tapped tuning ring on it.
I've got it 30' up next to the house. It seems to work well hearing as good as any I've put up in its class. Everything is DX right now, so that isn't saying too much.
As for some SWR bandwidth info, the MFJ-209 reads it like this from the end of the coax in the shack:
2.1:1 --------------- 29.080
1.5:1 --------------- 28.515
1.2:1 --------------- 28.095 (lowest reading without further tuning)
1.3:1 --------------- 27.555
1.4:1 --------------- 27.385
1.5:1 --------------- 27.050
2.1:1 --------------- 26.295
More length and tap point fine tuning would likely get it a little different, but it isn't too bad for a pile of spare parts thrown together.