Posted 10 January 2011 - 08:08 AM
I tried various ways of matching but ended up with the first 1/4 turn made from brass sheet about 5mm wide which distance to the reflector was adjusted for minimum reflected power.
I had good results but find patches easier to transport and mount.
Posted 11 January 2011 - 08:30 AM
Posted 11 January 2011 - 10:45 AM
Edited by Terry, 11 January 2011 - 02:21 PM.
Posted 14 January 2011 - 08:04 AM
H/W = .625
I computed that from Zo = 138log(4H/d) for a single wire over infinite ground plane.
So if I keep the input feed short enough that resonation isn't a problem, I can run it a short length vertically and then run the strip 90 degrees perpendicular to it.
My question is whether the whole strip needs to be that height or if it should wind upward and finish at that height? Any idea?
Posted 14 January 2011 - 10:51 AM
Mine both started low and got higher as they went round but not as much as the normal pitch. I dont think it is critical but I had no way to test the effects apart from the SWR. From memory the strip started very close to the reflector, probably 1mm gap, the strip was soldered to the side of the N connector pin and the tip cut off.
Hope this helps.
Posted 28 January 2011 - 02:02 PM
Posted 28 January 2011 - 02:04 PM
Posted 28 January 2011 - 02:06 PM
Edited by dalbert02, 28 January 2011 - 02:06 PM.
Posted 28 January 2011 - 02:09 PM
Edited by dalbert02, 30 January 2011 - 08:38 PM.
Posted 28 January 2011 - 02:11 PM
Edited by dalbert02, 28 January 2011 - 02:11 PM.
Posted 28 January 2011 - 02:16 PM
Posted 07 December 2011 - 10:17 AM
This is the Turnstile over reflector antenna he has spoken about, well, sort of. I never saw cyberFlyer's antenna. I used vector phasing to obtain a .98 axial ratio without any kind of phasing system to match it other than the reactive vectors of round wire. The reflector was the killer. That's where Hugo came in. Hugeone helped me in modeling this one and tweaked it to perfection since I couldn't seem to simulate the ground plane properly.
The cool thing about this antenna: you can adjust the gain for between 5 and 10 dbic. I only have it perfected for 9.5dbic. I was hoping to get 5 dbic, actually, but... well... I'm happy with this. Will work on the 5dbic one later.
As always, tutorials will be published.
@RC-CAM - If you want the details early, Email me
Posted 07 December 2011 - 02:19 PM