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References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[TowerTalk\]\s+OptiBeam\s+OB2\-40M\s*$/: 41 ]

Total 41 documents matching your query.

1. [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Wed, 19 May 2021 16:34:34 -0700
One of the radio clubs I belong to is interested in buying an OptiBeam OB2-40M two-element 40 meter Moxon Yagi. Optibeam is kind of vague on wind survival specifications. Their website indicates "Win
/archives//html/Towertalk/2021-05/msg00066.html (7,945 bytes)

2. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Bruce Jungwirth <k0son@frontiernet.net>
Date: Wed, 19 May 2021 18:48:09 -0500
Did you check with the guys at DX Engineering? They may be able to help you. K0SON, Bruce Sent from my iPad _______________________________________________ ___________________________________________
/archives//html/Towertalk/2021-05/msg00067.html (8,165 bytes)

3. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Charles Morrison <junkcmp@gmail.com>
Date: Wed, 19 May 2021 20:07:03 -0400
130kph=80.7mph for antenna, weather & racecars _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://l
/archives//html/Towertalk/2021-05/msg00068.html (8,232 bytes)

4. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Wed, 19 May 2021 19:13:47 -0700
Yes, I understand the units conversion, Charlie. That's not the problem. Strictly speaking the specification says that the lateral force on the antenna in a 130 km/h wind is 430 newtons (96.6 lbs). I
/archives//html/Towertalk/2021-05/msg00071.html (8,935 bytes)

5. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: "Peter Voelpel" <dj7ww@t-online.de>
Date: Thu, 20 May 2021 08:57:00 +0200
That 130km/h figure is not the wind survival but the reference wind velocity for the wind load of 500N. 130km/h is the standard reference for stress calculations in Germany used for all locations exc
/archives//html/Towertalk/2021-05/msg00073.html (9,659 bytes)

6. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Thu, 20 May 2021 01:25:08 -0700
I have owned an OB2-40 (the non-Moxon version) for ten years and it has held up just fine to ridiculous wind gusts on my southern Arizona hillside.  The antenna is built like the proverbial tank and
/archives//html/Towertalk/2021-05/msg00074.html (10,226 bytes)

7. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Ignacy Misztal <no9e@arrl.net>
Date: Thu, 20 May 2021 13:54:41 -0400
OB40-M weighs 35 kg (77 lb) and by specs it covers all of 40m with SWR < 2. A shortened Moxon from JK Antennas: JK 402-Piccolo with coils weighs 88 lb and covers only 250 KHz. A full size Moxon JK420
/archives//html/Towertalk/2021-05/msg00079.html (11,135 bytes)

8. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Mike Zak <mike@brookblue.com>
Date: Thu, 20 May 2021 18:26:25 +0000
In the past 18 years I have owned a variety of Optibeam yagis, including two OB2-40 2el yagis and an OB4-40 4el. I also have an OB3-40 in the process of going up on a tower. Mechanically, they are al
/archives//html/Towertalk/2021-05/msg00080.html (14,035 bytes)

9. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: "Salvatore [\"Ted\"] K2QMF" <k2qmf@juno.com>
Date: Thu, 20 May 2021 14:54:39 -0400
I agree with Mike, The OB2-40 is a great antenna! I have one up about 80 feet.  See my QRZ page! It replaced a Cushcraft 402-CD at the same height! The OB2-40 runs rings around the 402! A difference
/archives//html/Towertalk/2021-05/msg00081.html (15,720 bytes)

10. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: john@kk9a.com
Date: Fri, 21 May 2021 13:01:01 -0500
The OptiBeam OB2-40M appears to be a true Moxon. A Moxon, named after G6XN, is a rectangle where half the rectangle is the driven element and the other half is the reflector. To my knowledge JK does
/archives//html/Towertalk/2021-05/msg00082.html (8,651 bytes)

11. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Dave Thompson <thompson@mindspring.com>
Date: Fri, 21 May 2021 14:23:44 -0400 (GMT-04:00)
That optibeam sounds great but I reburbed my old 2 el Cushcraft 40 and its still a killer. I see no reason to change. The cushcraft usually beat out a 3 el Telerex at n4RJ and several 4 el KLM 40's n
/archives//html/Towertalk/2021-05/msg00083.html (8,305 bytes)

12. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Fri, 21 May 2021 12:29:49 -0700
Thank you sharing that information, Dave. I am curious what rotator you are using at your QTH? We are contemplating some sort of 10 to 30 MHz log periodic (like the InnovAntennas DELPA-13 or the M2 1
/archives//html/Towertalk/2021-05/msg00084.html (11,926 bytes)

13. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Mike Zak <mike@brookblue.com>
Date: Fri, 21 May 2021 19:30:17 +0000
A lot of this, IMO, depends on the specifics of any given station and its location. A site that is HFTA-friendly can compensate a lot for an antenna thats not EZNEC friendly. Im pretty confident that
/archives//html/Towertalk/2021-05/msg00085.html (10,155 bytes)

14. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: "Peter Voelpel" <dj7ww@t-online.de>
Date: Fri, 21 May 2021 21:50:18 +0200
That is hard to believe unless there is too much interaction between the antennas and makes them useless. Or all antennas except the Cushcraft are wrong assembled. Are all these antennas at the same
/archives//html/Towertalk/2021-05/msg00086.html (8,392 bytes)

15. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 21 May 2021 14:16:07 -0700
Sorry, but I don't believe any of that.  It sounds purely anecdotal. 73, Dave  AB7E On 5/21/2021 11:23 AM, Dave Thompson wrote: That optibeam sounds great but I reburbed my old 2 el Cushcraft 40 and
/archives//html/Towertalk/2021-05/msg00087.html (8,536 bytes)

16. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 21 May 2021 14:13:52 -0700
Well. I started out with a Prosistel PST-61D, and in addition to the OB2-40 I have a Optibeam OB16-3 on the mast.  It worked fine for a few years, but eventually the wind gusts here stripped a sectio
/archives//html/Towertalk/2021-05/msg00088.html (17,706 bytes)

17. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: <john@kk9a.com>
Date: Fri, 21 May 2021 20:28:16 -0400
VE6WZ has an interesting webpage on Cushcraft's loading coil construction (68 turns of 12AWG wire) and its loss: https://www.qsl.net/ve6wz/CC_coil.html John KK9A That optibeam sounds great but I rebu
/archives//html/Towertalk/2021-05/msg00089.html (8,280 bytes)

18. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: W0MU Mike Fatchett <w0mu@w0mu.com>
Date: Fri, 21 May 2021 19:13:55 -0600
Not to mention all the issues people have had with the connections of those coils. John KK9A That optibeam sounds great but I reburbed my old 2 el Cushcraft 40 and its still a killer. I see no reason
/archives//html/Towertalk/2021-05/msg00090.html (9,035 bytes)

19. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: Wes <wes_n7ws@triconet.org>
Date: Sat, 22 May 2021 07:40:19 -0700
Unfortunately, there is some bad info there.  IIRC Brian has updated his coil program several times and the answers are much different with the newer version.  The Cushcraft coil is nowhere near as b
/archives//html/Towertalk/2021-05/msg00091.html (11,419 bytes)

20. Re: [TowerTalk] OptiBeam OB2-40M (score: 1)
Author: VE6WZ_Steve <ve6wz@shaw.ca>
Date: Sat, 22 May 2021 09:11:50 -0600
Wes, You are correct. The original numbers for the CC coils from Brian's program were far too pessimistic, especially regarding his form loss algorithm. Brians new coil program is more realistic. In
/archives//html/Towertalk/2021-05/msg00092.html (13,734 bytes)

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