2m/432 Antennas


montanaaardvark
 


Since '03, I'd been using the same antenna for 6 and 2m, a log periodic that was really just a 6m antenna but which worked "OK" on 2. 

As I'm spending most of my operating time on 6m, I upgraded that antenna for more gain on 6, but that's a pure 6m yagi and I threw away 2m.  I'm looking for any experience with or pointers to interlaced 2m/432 yagis.  I may be able to put one of those up now.  My interest is the weak signal/SSB/FT8 on both bands.

Any recommendations? 


73,
Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


rich bassett
 

Time to become a real ham and get on HF.  

On Thursday, July 7, 2022 at 11:25:03 AM PDT, montanaaardvark <boblombardi@...> wrote:



Since '03, I'd been using the same antenna for 6 and 2m, a log periodic that was really just a 6m antenna but which worked "OK" on 2. 

As I'm spending most of my operating time on 6m, I upgraded that antenna for more gain on 6, but that's a pure 6m yagi and I threw away 2m.  I'm looking for any experience with or pointers to interlaced 2m/432 yagis.  I may be able to put one of those up now.  My interest is the weak signal/SSB/FT8 on both bands.

Any recommendations? 


73,
Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


montanaaardvark
 


Been on HF since 1976 and still am.  Gathering my last couple of cards for 8BDXCC. 

The only band I haven't operated on from 1.8 to 1300 MHz has been the 60m allocation.


--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


Charles VA7CPC Cohen
 

FWIW --

Elk antennas and Arrow antennas are both used heavily by 2m/70cm satellite stations.

The Arrows are cross-polarized Yagis.  The Elks aren't Yagis, but they have several dB of gain over a dipole.

. Charles / va7cpc

Virus-free. www.avg.com


montanaaardvark
 

Thanks, Charles.

I know the Arrow antennas.  I've seen them at hamfests for years, but Elk antennas don't ring a bell. 

I'll go look.


73,
Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


david vanhorn
 


On Fri, Jul 8, 2022 at 8:35 PM montanaaardvark <boblombardi@...> wrote:
Thanks, Charles.

I know the Arrow antennas.  I've seen them at hamfests for years, but Elk antennas don't ring a bell. 

I'll go look.


73,
Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for



--
K1FZY (WA4TPW) SK  9/29/37-4/13/15


Steve W3AHL
 

Avoid the Cushcraft VHF/UHF interlaced Yagi's, such as the A270-10.  They use a single feed point with a T-connector to drive both driven elements.  Since the 2M antenna is resonant as a 3/4 WL antenna at UHF, the UHF pattern is really messed up.  I worked with a local ham to add a VHF/UHF duplexor to isolate the two driven elements, but the gamma match tube for 2M DE was too short.  Lengthening it allowed it to tune, but the element spacicng really needed to be changed to get a decent pattern, which wasn't worth the effort.  He finally returned the antenna to MFJ for credit.

Steve, W3AHL


montanaaardvark
 

On Wed, Jul 13, 2022 at 10:51 AM, Steve W3AHL wrote:
Avoid the Cushcraft VHF/UHF interlaced Yagi's, such as the A270-10.  They use a single feed point with a T-connector to drive both driven elements.  Since the 2M antenna is resonant as a 3/4 WL antenna at UHF, the UHF pattern is really messed up.  I worked with a local ham to add a VHF/UHF duplexor to isolate the two driven elements, but the gamma match tube for 2M DE was too short.  Lengthening it allowed it to tune, but the element spacicng really needed to be changed to get a decent pattern, which wasn't worth the effort.  He finally returned the antenna to MFJ for credit.

Steve, W3AHL
Thanks, Steve.  That's very valuable input. 

While I know the arrow beams and guys who have worked the satellites with one, my intent would be weak signal -- SSB, CW, FT8 or something like that.  Those are conventionally horizontally polarized, so the way Arrow has them 90 degrees apart would be less than optimum.

I looked up the Elk Antennas after Charles' post and while I'm replacing a log periodic, I'm leaning toward a Yagi, but that's as specific as I've gotten.  Something like 5 elements on each band sounds simple.  The Elk antenna I looked at doesn't even claim any gain or other specs, other than being a good match on both bands. 

I replaced my 6m LPDA with a Directive Systems Engineering 5 element yagi that I'm happy with, so I checked them first.  I didn't see any interlaced 2/432 antennas.


73,
Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for