GPA 27 problems

[8valve]

hi all,
as my first post here (there is no introducing part )
ive got a problem with my 1/2 wave GPA antenna,
its this one;
GPA 27 1/2 BASISANTENNE - Handelsonderneming Dile - Handelsonderneming Dile
it rests on a alu pole thats 5,5 meter high
the swr stays on 1:5 on every channel from 26 to 30mhz

few things that i've tried;
new cable
new plugs
radio is about 10 meters from the antenna
3 swr meters gave the same value's
its a new radio
the antenna foot is 7 meters away from any obstacle
beyond the 7 meters there is my house and shed but they are just half a meter higher than the pole is

i just cant figure it out

 

[Marconi]

hi all,
as my first post here (there is no introducing part )
ive got a problem with my 1/2 wave GPA antenna,
its this one;
GPA 27 1/2 BASISANTENNE - Handelsonderneming Dile - Handelsonderneming Dile
it rests on a alu pole thats 5,5 meter high
the swr stays one 1:5 on every channel from 26 to 30mhz

few things that i've tried;
new cable
new plugs
radio is about 10 meters from the antenna
3 swr meters gave the same value's
its a new radio
the antenna foot is 7 meters away from any obstacle
beyond the 7 meters there is my house and shed but they are just half a meter higher than the pole is

i just cant figure it out

8valve, welcome to the forum.

I have no idea regarding you results, but I do tend to hear guys that complain when their meters seem to be stuck on 3.0:1 instead of 1.5:1.

I did notice one thing in this image that IMO shows a bad installation procedure however and I hope you didn't follow this suggestion:

GPA 27 1/2 BASISANTENNE

Check out that the metal mast is extended up above the mounting bracket a few inches and is projecting up beside the radiator. In my experience this has caused me problems with an A99 installation, but I can't remember exactly what the problem was.

I have also read warnings regarding such installation procedures by others and at least one manufacture pointed such a problem out in his manual.

Sorry I couldn't be of more help.

Good luck and keep us posted if you find a solution.

 

[8valve]

i installed it as high in the pole as possible
so the pole itself doesnt reflect on the antenne itself, only the coil is next to the pole

btw the pole is aluminum

 

[W5LZ]

What's wrong with an SWR of 1.5:1? I don't see where you have a problem at all. There's no significant difference between that 1.5:1 and a 1:1 SWR.
- 'Doc

 

[8valve]

What's wrong with an SWR of 1.5:1? I don't see where you have a problem at all. There's no significant difference between that 1.5:1 and a 1:1 SWR.
- 'Doc

made with paint a sketch of how the meter stand when i PTT

the black line is how it stand in real life

 

[Marconi]

What's wrong with an SWR of 1.5:1? I don't see where you have a problem at all. There's no significant difference between that 1.5:1 and a 1:1 SWR.
- 'Doc

'Doc, I took his post to say he showed 1.5:1 SWR from 26-30 mhz, and that doesn't sound reasonable to me. Without really knowing, it smacks of a lot of feed line loss.

 

[BOOTY MONSTER]

"the swr stays one 1:5 on every channel from 26 to 30mhz"

4 MHz of bandwidth does seem odd for that antenna .
it looks like a relabeled sirio GPE 27 1/2 minus the audio ball on top .

CB 27 MHz Base Antenna, GPE 27 5/8, GPS 27 1/2

 

[8valve]

feedline loss would be possible
EXCEPT, i use a same length cable for my homebrew dipole
and that one was within 15 min swr 1:1
ive got a roll of cable that i use for everything i do

i know that the antenna isnt designed for 26 tot 30mhz
but my transmitter can do it, so i did that to double check the results to see if it improved on the lower and higher side of the cb band
and it didnt

 

[AudioShockwav]

I think i am mis understanding.
The picture you are showing, with the Black line would be above a 5 to 1 swr when you press the PPT on the Mic, not good.
Is this correct?

 

[AudioShockwav]

I think it is a communication error, I Think he means it is 5 to 1 across the range.

73
Jeff

 

[8valve]

yes it is correct, its far in the red on every channel i can transmit on

 

[gamegetter]

yes it is correct, its far in the red on every channel i can transmit on

how much power are you transmitting with?

 

[8valve]

i transmit on 40watts FM
with this radio;
www.cbradio.nl: Pictures, Manual and Specifications Intek HR5500 All-Mode Mobile Export Radio
ive tried my good old President Grant with 10watts
www.cbradio.nl: Picture, Manual and Specifications of the President Grant CB-Radio
same problems so it isnt the radio

the antenna should hold up to 500watts
so im not pushing the thing to its limits

 

[gamegetter]

i'm not so sure that the meter is able to handle the power.

 

[8valve]

all the meters that i have a rated up to 100watts
so im not pushing those too