[amsat-bb] Homebrew Up-Dated Eggbeater Antenna (correction)
glasbrenner at mindspring.com
Tue Mar 15 20:52:35 UTC 2016
I have a 500' roll. Send me a stamped padded envelope or label for a usps flat rate box and how many feet you'd like.
In about 10 years of offering I've never had a taker though.
73, Drew KO4MA
Sent from my iPhone
> On Mar 15, 2016, at 4:45 PM, Joe <nss at mwt.net> wrote:
> Main problem seems to be the 93 ohm coax,,,
> anyone got a short piece?
> Joe WB9SBD
> The Original Rolling Ball Clock
> Idle Tyme
>> On 3/15/2016 3:11 PM, Robert Bruninga wrote:
>> Although my comments are true, I had not looked at the "updated" web page:
>> It appears he addressed all those issues and has an eggbeater design that
>> does address those same issues. If that works, then that is the same thing
>> I was talking about and seems to be a good approach. I'd love to see a
>> cookoff between the two antennas. Bob...
>> -----Original Message-----
>> From: Robert Bruninga [mailto:bruninga at usna.edu]
>> Sent: Tuesday, March 15, 2016 1:32 PM
>> Subject: RE: [amsat-bb] Homebrew Up-Dated Eggbeater Antenna
>> My 2 cents:
>> The problem with Eggbeaters is that their design goal (omni coverage) sounds
>> good but also means, by definition, equally poor in all directions.
>> There is no such thing as "gain" for an omni. The closer its gain
>> approaches 3D omni, in all directions, then the closer its gain approaches
>> 0 dBi. Of course, placed over a ground plane, then they can achieve 3
>> Now, on the other hand, satellites are nowhere near omni located. They are
>> 10dB or more farther away on the horizon than when they are overhead.
>> So you don't need as much gain at all overhead as you need on the horizon.
>> Further, satellites spend more than 70% of all pass times below 22 degrees!
>> (where they are weak) and only 5% of their time above 45 degrees where they
>> are 10 dB stronger.
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