How do you tune a helical antenna?

[whakahere]

I need some advice how I go about tuning a helical antenna on a spectrum analyzer. I know someone who has one and I will have the chance to plug in my 5.8ghz homemade antenna to tune it but I have no clue on the process.

What are the steps I need to take?

[Mictronics]

Tuned mine by adjusting the distance between groundplane and the first quarter of the first loop, starting from feedpoint. (Including the wave trap match I used)

[whakahere]

so by doing this this will shift the frequency up and down or improve the swr? My goal is to get as close to 5885mhz as I can and with the best SWR as I can.

So I can pretty much glue most of the antenna down?

[Mictronics]

Yes, it will shift the resonating frequency.

[whakahere]

Here is the untuned helical. This one is a 4 turn. Going to make a 6 next.

[Mictronics]

Looks excellent!

[whakahere]

Looks excellent!

well thanks to you. Your pictures on your website helped and gave me a few ideas how to build it.

[Mictronics]

So Ihope the result with the analyzer is how the helix looks.
Otherwise you can send her over here and I will pimp your flight.

[whakahere]

So Ihope the result with the analyzer is how the helix looks.
Otherwise you can send her over here and I will pimp your flight.

cheers mate, first I am going to make another. This time a 6 turn and a 8 turn and right hand polarized like my long ranged antennas. I made this one for my stunt wing ... it uses left hand polarized. That is a job for tomorrow now that I have a idea how I am going to go about building them (and my little jig made).

[whakahere]

Building has started. Oh I am using paper backed PCB from Conrad. easy to cut with a knife and quicker to dremel down than fibreglass PCB. Much easier to drill little holes in too. I wish I could find this without copper on though so I could use it as the foamer as well. Might try my heatgun (well father in laws .. "I borrowed it") to heat up the copper to see if I can peal it off.

I am going to make two 6 turns, 8 turn, 10(or 14) and some with a larger base as well to see the difference. I am giving one of the 6 turns to a guy in holland. People have helped me with this hobby it is time I returned the favour.