08-09-2017, 08:35 PM
Hi all,
I've just converted my dish (2m) to a Short Backfire antenna on 70cm.
(because I thought it wouldn't be too hard, two days later...)
(Matching blues, definitely well below 50 ohms at the dipole feed)
(I scrapped the loli-pop feed in coax and went for a wide dipole only
to convert it to an unequal folded dipole)
Bandwidth about 1%, seems all in the feed.
Bandwidth fixed as per "Improved SBFA" in doc SBFA_GBT_187.pdf a 1998 Radio Astronomy article.
I just added the 10.78 inch front disk. I now have well over 10MHz.
Pixture on my website http://www.unixservice.com.au/hamradio/antenna/
So, does anybody do Circular on 70cm?
=== Answer, no ===
Circular,. HB9Q has Circular so as not to "miss" anybody. He asked for either H or V.
I've tried EME on five moon passes thus far. Nothing, absolutely nothing heard and nobody has heard me either.
Back to the Drawing Board.
2C39
Alan VK2ZIW
I've just converted my dish (2m) to a Short Backfire antenna on 70cm.
(because I thought it wouldn't be too hard, two days later...)
(Matching blues, definitely well below 50 ohms at the dipole feed)
(I scrapped the loli-pop feed in coax and went for a wide dipole only
to convert it to an unequal folded dipole)
Bandwidth about 1%, seems all in the feed.
Bandwidth fixed as per "Improved SBFA" in doc SBFA_GBT_187.pdf a 1998 Radio Astronomy article.
I just added the 10.78 inch front disk. I now have well over 10MHz.
Pixture on my website http://www.unixservice.com.au/hamradio/antenna/
So, does anybody do Circular on 70cm?
=== Answer, no ===
Circular,. HB9Q has Circular so as not to "miss" anybody. He asked for either H or V.
I've tried EME on five moon passes thus far. Nothing, absolutely nothing heard and nobody has heard me either.
Back to the Drawing Board.
2C39
Alan VK2ZIW