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CX2SA > SATDIG 04.05.19 00:14l 1083 Lines 42882 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.SAL.URY.SOAM
To : SATDIG@WW
Today's Topics:
1. Re: ARRL Antenna book, eggbeater antenna designs (John Brier)
2. Re: ARRL Antenna book, eggbeater antenna designs (not)
(Robert Bruninga)
3. Re: ARRL Antenna book, eggbeater antenna designs (Jeff Johns)
4. Re: Anyone on CAS-4B?! (Peter Goodhall (2M0SQL))
5. Re: ARRL Antenna book, eggbeater antenna designs (not)
(Devin L. Ganger)
6. Re: ARRL Antenna book, eggbeater antenna designs (not)
(Clayton Coleman W5PFG)
7. Re: ARRL Antenna book, eggbeater antenna designs (David Swanson)
8. Re: ARRL Antenna book, eggbeater antenna designs (not)
(David Johnson)
----------------------------------------------------------------------
Message: 1
Date: Fri, 3 May 2019 17:27:56 -0400
From: John Brier <johnbrier@?????.???>
To: "Devin L. Ganger" <devin@????????.???>
Cc: AMSAT BB <amsat-bb@?????.???>, Ted <k7trkradio@???????.???>
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
Message-ID:
<CALn0fKMQO4q8vg9nHoVK1M1vqR0+CeGFTWN52NhmXtwq1BJFnQ@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
There is someone on the AMSAT-NA Facebook group who built an egg beater
setup with preamps at the mast who seems to be having success. He seems to
be really good at fashioning metal and the results look impressive from a
purely mechanical and aesthetic perspective.
Does anyone remember who I'm talking about?
If we figure it out you could ask him for info on his setup and experience.
73, John Brier KG4AKV
On Fri, May 3, 2019, 17:09 Devin L. Ganger via AMSAT-BB <amsat-bb@?????.???>
wrote:
> Resending this to the list, instead of just to Sean. Sorry, Sean!
>
> I have an Elk for my D72A and that works fine when the weather cooperates.
> Note below where I say I *replaced* the Baofengs - they're no longer in
> play, for anyone named David Swanson who cares to take a swipe at me for
> those.
>
> For those times when it doesn't (I live in Western Washington, so that's
> quite a bit) I'm building something to mount on top of the house to use
> with my Yaesu 857D until I can afford a rotator + M2 LEO pack or something
> similar. We just bought our house, have two kids in college, and are
> actively trying to get out of debt within the next year, so just going and
> buying a ton of expensive hardware is not in the budget at this time.
> Otherwise I would be asking about towers. :)
>
> I understand that the eggbeaters have their flaws, but I've read claims
> that the Eggbeater-II design (which is more Moxon-like from what I
> understand) offers better gain at the horizon than either the pure
> eggbeater or Moxon. Is this not the case?
>
>
> --
> Devin L. Ganger (WA7DLG)
> email: devin@????????.???
> web: Devin on Earth
> cell: +1 425.239.2575
>
> > -----Original Message-----
> > From: Ted Krempa <k7trkradio@???????.???>
> > Sent: Friday, May 3, 2019 1:56 PM
> > To: Devin L. Ganger <devin@????????.???>; AMSAT BB <amsat-
> > bb@?????.???>
> > Subject: RE: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
> >
> > Hi Devin, frankly the 'eggbeater' days have come and gone in the
> efficiency
> > dept.
> >
> > Attached is an article from QST on the Moxon turnstile, a much better
> option.
> > Better than that is an Elk on a 'rat shack rotor at 15-20 deg fixed el.
> >
> > If interested, I can send you my files direct on either
> >
> > 73, Ted
> > K7TRK
> >
> > -----Original Message-----
> > From: AMSAT-BB [mailto:amsat-bb-bounces@?????.???? On Behalf Of Devin
> > L.
> > Ganger via AMSAT-BB
> > Sent: Friday, May 3, 2019 1:19 PM
> > To: AMSAT-BB@?????.???
> > Subject: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
> >
> > Greetings, programs!
> >
> > I'm looking to work with my son (who will be studying to get his
> Technician
> > license later this month) on building a UHF/VHF pair of eggbeater
> antennas.
> > I've found a few papers online, but does anyone have a good reference to
> a
> > detailed design?
> >
> > Does the ARRL Antenna book latest edition have any significant coverage
> of
> > eggbeaters at all? I have an older version that has nothing.
> >
> > Also, most of the designs I see are for a single band. If you're
> deploying a pair
> > for satellite operations, do you simply attach them through a duplexer?
> > I have a Diamond MX-72N that I picked up a while ago for using with dual
> > Baofengs, but it's been sitting in my drawer since I picked up my
> TH-D72A.
> > It has a 1.6~150MHz lead and a 350~460MHz lead.
> >
> > Thanks in advance for any pointers you might have.
> >
> >
> > --
> > Devin L. Ganger (WA7DLG)
> > email: devin@????????.???<????????????@????????.???>
> > web: Devin on Earth<http://www.devinonearth.com/>
> > cell: +1 425.239.2575
> >
> > _______________________________________________
> > Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> > to all interested persons worldwide without requiring membership.
> Opinions
> > expressed are solely those of the author, and do not reflect the
> official views
> > of AMSAT-NA.
> > Not an AMSAT-NA member? Join now to support the amateur satellite
> > program!
> > Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 2
Date: Fri, 3 May 2019 17:32:27 -0400
From: Robert Bruninga <bruninga@????.???>
To: AMSAT-BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
(not)
Message-ID: <80553438fe9a541c29d0c638b3d7e087@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Eggbeaters are ideal antennas for omnidirectional coverage with dual
polarization for strong signals with minimum fades....
But like any antenna, to get gain somewhere, you have to give up gain
elsewhere. Here are all the issues and my opinions.
1) Satellites on the horizon are 10 dB farther away than ones above 22
degrees (2000 miles vs 700 miles).
2) Splitting gain into circular polarization (Eggbeaters) loses 3 dB
compared to incoming linear polarization
3) Small sats usually have linear antennas or, if they have cross
polarization then even if they are RHCP when approaching, they may be LHCP
going away, thus you still have a 50/50 chance of having a polarization
mismatch, though having both polarizations will minimize most fades.
4) Most small Amateur sateliltes have less than 1W transmitters and simply
cannot be heard on the horizon without several dB gain.
My Conslusions are:
1) An Egg beater is ideal for STRONG satellites (Think ISS with 10 Watts).
It will minimize fades horizon to horizon.
2) But there are NO, NONE, NADA current amateur satellites (not even the
ISS right now) at that power level.
4) Hence an eggbeater even with a dB or so gain on the horizon simply is
not going to hear anything until the satellite gets above about 20 degrees
(when it is 10 dB closer)
5) So, why even bother with an eggbeater.
6) Use a simple 19.5" quarter wave vertical over a ground plane (for 2m).
It will have 5 dBi gain above about 15 degrees (several dB better than an
eggbeater).
7) and it will ALSO WORK even better as a 7 dBi gain UHF antenna (3/4 wave
vertical) above about 25 degrees up to 70 degrees (6 dB better than an
Eggbeater)...
AND it is DUAL band as well! (on the same coax!)
BUT, what about the donut hole overhead for these vertical antennas?
Forgetaboutit.!.... The satellite is only above 70 degrees about 1% of
the total pass times per day! And then for less than about 30 seconds!
To visualize the orbit actual geometry see the scale plot on:
http://aprs.org/LEO-tracking.html
So, in my humble opinion, a 19.5" vertical whip antenna in the middle of a
car roof (neat ground plane) will give pretty good satellite coverage. It
will have some fades due to only one polarization, but the strong part of
the cycle will be 3 dB stronger than it would be on a dual polarizatiaon
antenna. And you don't have to be parked on a mountain. Since again, no
omni antenna can hear these weak satellites on the horizon anyway, so as
long as the trees are far enough away to give you sky above about 20
degrees, you will have about the best coverage you can get for about a 20"
of copper wire and a nice ground plane..
In my opinion anyway.
AND*** If you want to hear them all the way horizon to horizon, buy a $65
TV rotator and attach a small 5 to 6 element beam tilted up at about 15
degrees and hear them all! See above web page...
Bob, Wb4APR
-----Original Message-----
From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of Devin L. Ganger
via AMSAT-BB
Sent: Friday, May 3, 2019 4:19 PM
To: AMSAT-BB@?????.???
Subject: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
Greetings, programs!
I'm looking to work with my son (who will be studying to get his
Technician license later this month) on building a UHF/VHF pair of
eggbeater antennas. I've found a few papers online, but does anyone have a
good reference to a detailed design?
Does the ARRL Antenna book latest edition have any significant coverage of
eggbeaters at all? I have an older version that has nothing.
Also, most of the designs I see are for a single band. If you're deploying
a pair for satellite operations, do you simply attach them through a
duplexer? I have a Diamond MX-72N that I picked up a while ago for using
with dual Baofengs, but it's been sitting in my drawer since I picked up
my TH-D72A. It has a 1.6~150MHz lead and a 350~460MHz lead.
Thanks in advance for any pointers you might have.
--
Devin L. Ganger (WA7DLG)
email: devin@????????.???<????????????@????????.???>
web: Devin on Earth<http://www.devinonearth.com/>
cell: +1 425.239.2575
_______________________________________________
Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available to
all interested persons worldwide without requiring membership. Opinions
expressed are solely those of the author, and do not reflect the official
views of AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 3
Date: Fri, 3 May 2019 16:33:21 -0500
From: Jeff Johns <jeff30339@?????.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
Message-ID: <C7E22F46-FD83-4A7D-91AE-E0160DDDE77A@?????.???>
Content-Type: text/plain; charset=utf-8
Huh? I don?t know what you are talking about but I have been doing this for
over two decades. Sometimes experience matters.
Jeff WE4B
> On May 3, 2019, at 4:10 PM, Devin L. Ganger via AMSAT-BB
<amsat-bb@?????.???> wrote:
>
> Oh, that's right, you're the dude who's still butt-hurt because I called
people out about bullying new users who ask about tripods.
>
> You're the dude who assumed that since you never heard me TX that meant I
wasn't operating at all.
>
> You're the dude whose reading comprehension is lacking.
>
> And you seem to be the dude who thinks that if you know one aspect of
operating you know them all and can't ever admit ignorance.
>
> Please don't bother to respond to the thread any more -- I know I can't
trust any advice you might give, out of only the best of intentions, because
you make too many faulty assumptions.
>
> --
> Devin L. Ganger (WA7DLG)
> email: devin@????????.???
> web: Devin on Earth
> cell: +1 425.239.2575
>
>> -----Original Message-----
>> From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of David
>> Swanson via AMSAT-BB
>> Sent: Friday, May 3, 2019 1:58 PM
>> To: Sean Waite <waisean@?????.???>
>> Cc: AMSAT-BB@?????.???
>> Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
>>
>> Hi Sean!
>>
>> I don't recall seeing any name calling here until your post, I genuinely
want to
>> make sure the author of this thread who has sent numerous emails to this
list
>> explaining how to operate gets the best tips in regards to their planned
build.
>> I'm actually in the process of building the setup I recommended and will
plan
>> on doing a demo for folks sometime here soon, stay tuned!
>>
>> -Dave, KG5CCI
>>
>>> On Fri, May 3, 2019 at 3:51 PM Sean Waite <waisean@?????.???> wrote:
>>>
>>> Ah, yes, rather than maybe educate someone let's just berate them and
>>> functionally call them an idiot.
>>>
>>> Eggbeaters have a bad rap because they don't necessarily hear well.
>>> You may be making it into the bird but not hearing yourself, so you
>>> keep tuning around and calling trying to find yourself only to be
>>> deaf-ly QRMing other stations. I have no experience with them, but that's
>> what I've heard.
>>>
>>> 73,
>>> Sean WA1TE
>>>
>>> On Fri, May 3, 2019 at 4:49 PM David Swanson via AMSAT-BB <
>>> amsat-bb@?????.???> wrote:
>>>
>>>> Instead of building eggbeaters, pick up a few of these:
>>>>
>>>> http://www.mfjenterprises.com/Product.php?productid=MFJ-261
>>>>
>>>> You'll also need a pair of these:
>>>>
>>>> https://www.amazon.com/Coaxial-Cable-Female-SO239-
>> PL259/dp/B00KQHH7VC
>>>>
>>>> Hook those into your baofengs and you'll be just as effective on the
>>>> Satellites as you would with some homemade 'beaters.
>>>>
>>>> Good luck! 73!
>>>>
>>>> -Dave, KG5CCI
>>>>
>>>> On Fri, May 3, 2019 at 3:19 PM Devin L. Ganger via AMSAT-BB <
>>>> amsat-bb@?????.???> wrote:
>>>>
>>>>> Greetings, programs!
>>>>>
>>>>> I'm looking to work with my son (who will be studying to get his
>>>>> Technician license later this month) on building a UHF/VHF pair of
>>>>> eggbeater antennas. I've found a few papers online, but does anyone
>>>> have a
>>>>> good reference to a detailed design?
>>>>>
>>>>> Does the ARRL Antenna book latest edition have any significant
>>>>> coverage
>>>> of
>>>>> eggbeaters at all? I have an older version that has nothing.
>>>>>
>>>>> Also, most of the designs I see are for a single band. If you're
>>>> deploying
>>>>> a pair for satellite operations, do you simply attach them through
>>>>> a duplexer? I have a Diamond MX-72N that I picked up a while ago
>>>>> for using with dual Baofengs, but it's been sitting in my drawer
>>>>> since I picked
>>>> up my
>>>>> TH-D72A. It has a 1.6~150MHz lead and a 350~460MHz lead.
>>>>>
>>>>> Thanks in advance for any pointers you might have.
>>>>>
>>>>>
>>>>> --
>>>>> Devin L. Ganger (WA7DLG)
>>>>> email: devin@????????.???<????????????@????????.???>
>>>>> web: Devin on Earth<http://www.devinonearth.com/>
>>>>> cell: +1 425.239.2575
>>>>>
>>>>> _______________________________________________
>>>>> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum
>>>>> available to all interested persons worldwide without requiring
>> membership.
>>>> Opinions
>>>>> expressed
>>>>> are solely those of the author, and do not reflect the official
>>>>> views of AMSAT-NA.
>>>>> Not an AMSAT-NA member? Join now to support the amateur satellite
>>>> program!
>>>>> Subscription settings:
>>>>> https://www.amsat.org/mailman/listinfo/amsat-bb
>>>>>
>>>> _______________________________________________
>>>> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum
>> available
>>>> to all interested persons worldwide without requiring membership.
>>>> Opinions expressed
>>>> are solely those of the author, and do not reflect the official views
>>>> of AMSAT-NA.
>>>> Not an AMSAT-NA member? Join now to support the amateur satellite
>> program!
>>>> Subscription settings:
>>>> https://www.amsat.org/mailman/listinfo/amsat-bb
>>>>
>>>
>> _______________________________________________
>> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
>> to all interested persons worldwide without requiring membership. Opinions
>> expressed are solely those of the author, and do not reflect the official
views
>> of AMSAT-NA.
>> Not an AMSAT-NA member? Join now to support the amateur satellite
>> program!
>> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
expressed
> are solely those of the author, and do not reflect the official views of
AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 4
Date: Fri, 3 May 2019 22:40:19 +0100
From: "Peter Goodhall (2M0SQL)" <peter@????????.??.??>
To: Lapo Pieri IK5NAX <ik5nax@???????????.??>
Cc: AMSAT-BB@?????.???
Subject: Re: [amsat-bb] Anyone on CAS-4B?!
Message-ID:
<CAFvUaiqBUgHpnumN24eGuyGBjxB4SBxEp9Yj9UELD=k+SE4UNA@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Sorry I missed it, I was on FO-29
I'll look for you on CAS-4A/B but usually quiet in the evenings.
Peter 2M0SQL
On Fri, 3 May 2019, 22:35 Lapo Pieri IK5NAX via AMSAT-BB, <
amsat-bb@?????.???> wrote:
> Hi,
> I've tried to work a good pass of CAS-4B over Europe few minutes ago:
> calling
> cq for most of passes and listening over the bandwidth I got no responses
> and I haven't heard anyone...
> Just a case or the satellite is almost unused?
>
> 73, Lapo IK5NAX
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 5
Date: Fri, 3 May 2019 21:49:12 +0000
From: "Devin L. Ganger" <devin@????????.???>
To: Robert Bruninga <bruninga@????.???>, AMSAT-BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
(not)
Message-ID:
<DM5PR01MB2507271D9E0D43EEA96326BACA350@?????????????.????.????????????.???>
Content-Type: text/plain; charset="us-ascii"
Thank you, that is helpful discussion. Many points to ponder.
--
Devin L. Ganger (WA7DLG)
email: devin@????????.???
web: Devin on Earth
cell: +1 425.239.2575
________________________________
From: Robert Bruninga <bruninga@????.???>
Sent: Friday, May 3, 2019 2:32 PM
To: AMSAT-BB
Cc: Devin L. Ganger
Subject: RE: [amsat-bb] ARRL Antenna book, eggbeater antenna designs (not)
Eggbeaters are ideal antennas for omnidirectional coverage with dual
polarization for strong signals with minimum fades....
But like any antenna, to get gain somewhere, you have to give up gain
elsewhere. Here are all the issues and my opinions.
1) Satellites on the horizon are 10 dB farther away than ones above 22
degrees (2000 miles vs 700 miles).
2) Splitting gain into circular polarization (Eggbeaters) loses 3 dB
compared to incoming linear polarization
3) Small sats usually have linear antennas or, if they have cross
polarization then even if they are RHCP when approaching, they may be LHCP
going away, thus you still have a 50/50 chance of having a polarization
mismatch, though having both polarizations will minimize most fades.
4) Most small Amateur sateliltes have less than 1W transmitters and simply
cannot be heard on the horizon without several dB gain.
My Conslusions are:
1) An Egg beater is ideal for STRONG satellites (Think ISS with 10 Watts).
It will minimize fades horizon to horizon.
2) But there are NO, NONE, NADA current amateur satellites (not even the
ISS right now) at that power level.
4) Hence an eggbeater even with a dB or so gain on the horizon simply is
not going to hear anything until the satellite gets above about 20 degrees
(when it is 10 dB closer)
5) So, why even bother with an eggbeater.
6) Use a simple 19.5" quarter wave vertical over a ground plane (for 2m).
It will have 5 dBi gain above about 15 degrees (several dB better than an
eggbeater).
7) and it will ALSO WORK even better as a 7 dBi gain UHF antenna (3/4 wave
vertical) above about 25 degrees up to 70 degrees (6 dB better than an
Eggbeater)...
AND it is DUAL band as well! (on the same coax!)
BUT, what about the donut hole overhead for these vertical antennas?
Forgetaboutit.!.... The satellite is only above 70 degrees about 1% of
the total pass times per day! And then for less than about 30 seconds!
To visualize the orbit actual geometry see the scale plot on:
http://aprs.org/LEO-tracking.html
So, in my humble opinion, a 19.5" vertical whip antenna in the middle of a
car roof (neat ground plane) will give pretty good satellite coverage. It
will have some fades due to only one polarization, but the strong part of
the cycle will be 3 dB stronger than it would be on a dual polarizatiaon
antenna. And you don't have to be parked on a mountain. Since again, no
omni antenna can hear these weak satellites on the horizon anyway, so as
long as the trees are far enough away to give you sky above about 20
degrees, you will have about the best coverage you can get for about a 20"
of copper wire and a nice ground plane..
In my opinion anyway.
AND*** If you want to hear them all the way horizon to horizon, buy a $65
TV rotator and attach a small 5 to 6 element beam tilted up at about 15
degrees and hear them all! See above web page...
Bob, Wb4APR
-----Original Message-----
From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of Devin L. Ganger
via AMSAT-BB
Sent: Friday, May 3, 2019 4:19 PM
To: AMSAT-BB@?????.???
Subject: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
Greetings, programs!
I'm looking to work with my son (who will be studying to get his
Technician license later this month) on building a UHF/VHF pair of
eggbeater antennas. I've found a few papers online, but does anyone have a
good reference to a detailed design?
Does the ARRL Antenna book latest edition have any significant coverage of
eggbeaters at all? I have an older version that has nothing.
Also, most of the designs I see are for a single band. If you're deploying
a pair for satellite operations, do you simply attach them through a
duplexer? I have a Diamond MX-72N that I picked up a while ago for using
with dual Baofengs, but it's been sitting in my drawer since I picked up
my TH-D72A. It has a 1.6~150MHz lead and a 350~460MHz lead.
Thanks in advance for any pointers you might have.
--
Devin L. Ganger (WA7DLG)
email: devin@????????.???<????????????@????????.???>
web: Devin on Earth<http://www.devinonearth.com/>
cell: +1 425.239.2575
_______________________________________________
Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available to
all interested persons worldwide without requiring membership. Opinions
expressed are solely those of the author, and do not reflect the official
views of AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 6
Date: Fri, 3 May 2019 16:54:24 -0500
From: Clayton Coleman W5PFG <tasmac@?????.??>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
(not)
Message-ID: <47656b23-6a13-3cca-7765-120e3e2fb5c5@?????.??>
Content-Type: text/plain; charset=utf-8; format=flowed
WB4APR's summary matches my personal assessment of eggbeaters, having
tried them on LEO's myself for a period of test: Eggbeaters are mediocre
at best for our LEO, amateur satellite fleet.
There are situations eggbeaters may have their place:
1. A fixed installation, such as telemetry gathering, in which you
absolutely can't afford risk of mechanical rotor failure.
2. A backup to a directional array.
3. The satellite has a very strong downlink.
Beyond that I can't recommend them for anyone. I learned, like Bob said
below, that a 1/4 wave ground plane on 2m is as effective or better.
I've copied thousands of telemetry frames with an inexpensive, SO-239
chassis connector-based ground plane. This was in a very low-noise area
with no obstructions. Keep the feedline as short as possible, use
quality feedline, and consider use of RX preamplifier as necessary.
I will say this, people DO make contacts on eggbeaters. They also make
contacts with mobile whips and rubber ducks. Some folks are more
successful than others at this. On a regular basis I can quickly
ascertain when the other station in QSO with me is on an eggbeater or omni.
Two major factors at play can make or break an eggbeater being useful:
1. Terrain/obstructions. Eggbeaters in the middle of your forested
backyard are a total waste. Can you put them on the roof if it clears
the trees? Are you in the concrete jungle?
2. RFI/noise. Eggbeaters are far more prone to local RFI than a
directional antenna aimed at the satellite. I've seen some situations
where an omni couldn't copy a single telemetry frame, yet a 2 element
yagi was copying the telemetry in exactly the same observation point
from horizon to horizon.
In summary, I would recommend building an eggbeater with scrap materials
versus buying a commercial one, so that no tears are shed over lost
money once it's tossed into the rubbish bin.
73,
Clayton
W5PFG
On 5/3/2019 16:32, Robert Bruninga via AMSAT-BB wrote:
> Eggbeaters are ideal antennas for omnidirectional coverage with dual
> polarization for strong signals with minimum fades....
>
> But like any antenna, to get gain somewhere, you have to give up gain
> elsewhere. Here are all the issues and my opinions.
>
> 1) Satellites on the horizon are 10 dB farther away than ones above 22
> degrees (2000 miles vs 700 miles).
> 2) Splitting gain into circular polarization (Eggbeaters) loses 3 dB
> compared to incoming linear polarization
> 3) Small sats usually have linear antennas or, if they have cross
> polarization then even if they are RHCP when approaching, they may be LHCP
> going away, thus you still have a 50/50 chance of having a polarization
> mismatch, though having both polarizations will minimize most fades.
> 4) Most small Amateur sateliltes have less than 1W transmitters and simply
> cannot be heard on the horizon without several dB gain.
>
> My Conslusions are:
> 1) An Egg beater is ideal for STRONG satellites (Think ISS with 10 Watts).
> It will minimize fades horizon to horizon.
> 2) But there are NO, NONE, NADA current amateur satellites (not even the
> ISS right now) at that power level.
> 4) Hence an eggbeater even with a dB or so gain on the horizon simply is
> not going to hear anything until the satellite gets above about 20 degrees
> (when it is 10 dB closer)
> 5) So, why even bother with an eggbeater.
> 6) Use a simple 19.5" quarter wave vertical over a ground plane (for 2m).
> It will have 5 dBi gain above about 15 degrees (several dB better than an
> eggbeater).
> 7) and it will ALSO WORK even better as a 7 dBi gain UHF antenna (3/4 wave
> vertical) above about 25 degrees up to 70 degrees (6 dB better than an
> Eggbeater)...
>
> AND it is DUAL band as well! (on the same coax!)
>
> BUT, what about the donut hole overhead for these vertical antennas?
>
> Forgetaboutit.!.... The satellite is only above 70 degrees about 1% of
> the total pass times per day! And then for less than about 30 seconds!
>
> To visualize the orbit actual geometry see the scale plot on:
> http://aprs.org/LEO-tracking.html
>
> So, in my humble opinion, a 19.5" vertical whip antenna in the middle of a
> car roof (neat ground plane) will give pretty good satellite coverage. It
> will have some fades due to only one polarization, but the strong part of
> the cycle will be 3 dB stronger than it would be on a dual polarizatiaon
> antenna. And you don't have to be parked on a mountain. Since again, no
> omni antenna can hear these weak satellites on the horizon anyway, so as
> long as the trees are far enough away to give you sky above about 20
> degrees, you will have about the best coverage you can get for about a 20"
> of copper wire and a nice ground plane..
>
> In my opinion anyway.
>
> AND*** If you want to hear them all the way horizon to horizon, buy a $65
> TV rotator and attach a small 5 to 6 element beam tilted up at about 15
> degrees and hear them all! See above web page...
>
> Bob, Wb4APR
------------------------------
Message: 7
Date: Fri, 3 May 2019 16:55:13 -0500
From: David Swanson <dave@?????????????.???>
To: "Devin L. Ganger" <devin@????????.???>
Cc: AMSAT BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
Message-ID:
<CANq+eyVtYJ+8tb679d8aAO1m5-Hk1mQJCrVUjAL7aASTOCJ4pw@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
OK Devin since you want to do this in public ---
Yes, I'm one of the guys (AL6D is the other) you sent an out of thread
reply to back on April 24th scolding us like a school marm for not just
accepting people who are causing deliberate interference. You then
proceeded to use a bunch of snowflake words like "ableism" at me and Gabe.
I promptly told you to go to hell with your preaching, and I'll tell you
again now in public.
Back on topic, here's the low-down - if you're not actually making
contacts, then you're not operating. You're SWLing. Any old joe with an SDR
and a coat hanger can listen, and they might even hear something from time
to time, that is a far cry from being a successful op. I'm not going to
bother telling you about the success I've had on Satellites (you can figure
that out yourself if you care too) but rest assured I do have a clue.
Interestingly, you have made 36 replies to this list since 2016 (based on a
quick search) and have no doubt seen countless thread about Omni's,
tripods, and Eggbeaters. Yet you have never made a QSO, and still come in
here offering incorrect advice to others, all the while playing the family
oh so poor card, to explain why you would want to build a sub-par setup and
cause deliberate interference on the current LEO fleet. You sir are a
genuine troll of the highest order, I only replied in kind with my dummy
load post suggestion.
You can reply to this thread if you like - cause I'm just a guy and don't
claim to have any power over other people's speech. I please do request
though that you don't ever get on the birds, cause you're obviously
incapable of the basic functions necessary to operate.
73!
-Dave, KG5CCI
On Fri, May 3, 2019 at 4:10 PM Devin L. Ganger <devin@????????.???> wrote:
> Oh, that's right, you're the dude who's still butt-hurt because I called
> people out about bullying new users who ask about tripods.
>
> You're the dude who assumed that since you never heard me TX that meant I
> wasn't operating at all.
>
> You're the dude whose reading comprehension is lacking.
>
> And you seem to be the dude who thinks that if you know one aspect of
> operating you know them all and can't ever admit ignorance.
>
> Please don't bother to respond to the thread any more -- I know I can't
> trust any advice you might give, out of only the best of intentions,
> because you make too many faulty assumptions.
>
> --
> Devin L. Ganger (WA7DLG)
> email: devin@????????.???
> web: Devin on Earth
> cell: +1 425.239.2575
>
> > -----Original Message-----
> > From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of David
> > Swanson via AMSAT-BB
> > Sent: Friday, May 3, 2019 1:58 PM
> > To: Sean Waite <waisean@?????.???>
> > Cc: AMSAT-BB@?????.???
> > Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
> >
> > Hi Sean!
> >
> > I don't recall seeing any name calling here until your post, I genuinely
> want to
> > make sure the author of this thread who has sent numerous emails to this
> list
> > explaining how to operate gets the best tips in regards to their planned
> build.
> > I'm actually in the process of building the setup I recommended and will
> plan
> > on doing a demo for folks sometime here soon, stay tuned!
> >
> > -Dave, KG5CCI
> >
> > On Fri, May 3, 2019 at 3:51 PM Sean Waite <waisean@?????.???> wrote:
> >
> > > Ah, yes, rather than maybe educate someone let's just berate them and
> > > functionally call them an idiot.
> > >
> > > Eggbeaters have a bad rap because they don't necessarily hear well.
> > > You may be making it into the bird but not hearing yourself, so you
> > > keep tuning around and calling trying to find yourself only to be
> > > deaf-ly QRMing other stations. I have no experience with them, but
> that's
> > what I've heard.
> > >
> > > 73,
> > > Sean WA1TE
> > >
> > > On Fri, May 3, 2019 at 4:49 PM David Swanson via AMSAT-BB <
> > > amsat-bb@?????.???> wrote:
> > >
> > >> Instead of building eggbeaters, pick up a few of these:
> > >>
> > >> http://www.mfjenterprises.com/Product.php?productid=MFJ-261
> > >>
> > >> You'll also need a pair of these:
> > >>
> > >> https://www.amazon.com/Coaxial-Cable-Female-SO239-
> > PL259/dp/B00KQHH7VC
> > >>
> > >> Hook those into your baofengs and you'll be just as effective on the
> > >> Satellites as you would with some homemade 'beaters.
> > >>
> > >> Good luck! 73!
> > >>
> > >> -Dave, KG5CCI
> > >>
> > >> On Fri, May 3, 2019 at 3:19 PM Devin L. Ganger via AMSAT-BB <
> > >> amsat-bb@?????.???> wrote:
> > >>
> > >> > Greetings, programs!
> > >> >
> > >> > I'm looking to work with my son (who will be studying to get his
> > >> > Technician license later this month) on building a UHF/VHF pair of
> > >> > eggbeater antennas. I've found a few papers online, but does anyone
> > >> have a
> > >> > good reference to a detailed design?
> > >> >
> > >> > Does the ARRL Antenna book latest edition have any significant
> > >> > coverage
> > >> of
> > >> > eggbeaters at all? I have an older version that has nothing.
> > >> >
> > >> > Also, most of the designs I see are for a single band. If you're
> > >> deploying
> > >> > a pair for satellite operations, do you simply attach them through
> > >> > a duplexer? I have a Diamond MX-72N that I picked up a while ago
> > >> > for using with dual Baofengs, but it's been sitting in my drawer
> > >> > since I picked
> > >> up my
> > >> > TH-D72A. It has a 1.6~150MHz lead and a 350~460MHz lead.
> > >> >
> > >> > Thanks in advance for any pointers you might have.
> > >> >
> > >> >
> > >> > --
> > >> > Devin L. Ganger (WA7DLG)
> > >> > email: devin@????????.???<????????????@????????.???>
> > >> > web: Devin on Earth<http://www.devinonearth.com/>
> > >> > cell: +1 425.239.2575
> > >> >
> > >> > _______________________________________________
> > >> > Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum
> > >> > available to all interested persons worldwide without requiring
> > membership.
> > >> Opinions
> > >> > expressed
> > >> > are solely those of the author, and do not reflect the official
> > >> > views of AMSAT-NA.
> > >> > Not an AMSAT-NA member? Join now to support the amateur satellite
> > >> program!
> > >> > Subscription settings:
> > >> > https://www.amsat.org/mailman/listinfo/amsat-bb
> > >> >
> > >> _______________________________________________
> > >> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum
> > available
> > >> to all interested persons worldwide without requiring membership.
> > >> Opinions expressed
> > >> are solely those of the author, and do not reflect the official views
> > >> of AMSAT-NA.
> > >> Not an AMSAT-NA member? Join now to support the amateur satellite
> > program!
> > >> Subscription settings:
> > >> https://www.amsat.org/mailman/listinfo/amsat-bb
> > >>
> > >
> > _______________________________________________
> > Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> > to all interested persons worldwide without requiring membership.
> Opinions
> > expressed are solely those of the author, and do not reflect the
> official views
> > of AMSAT-NA.
> > Not an AMSAT-NA member? Join now to support the amateur satellite
> > program!
> > Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 8
Date: Fri, 3 May 2019 16:57:43 -0500
From: David Johnson <david.johnson.bbq@?????.???>
To: Robert Bruninga <bruninga@????.???>
Cc: AMSAT-BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
(not)
Message-ID:
<CAPz2khYW30qoRjhqaRRwpNO2NTPD_xKZUf_D1j4mnbmCTihQ6Q@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Completely agree with what Bob said and have one thing to add. I have had
personal experience using an eggbeater during an ARISS voice contact
(backup system). It did ok at the highest elevations of the pass, but
really struggled closer to the horizons. The eggbeater has been retired to
storage.
Dave Johnson
W9DWJ
On Fri, May 3, 2019 at 4:48 PM Robert Bruninga via AMSAT-BB <
amsat-bb@?????.???> wrote:
> Eggbeaters are ideal antennas for omnidirectional coverage with dual
> polarization for strong signals with minimum fades....
>
> But like any antenna, to get gain somewhere, you have to give up gain
> elsewhere. Here are all the issues and my opinions.
>
> 1) Satellites on the horizon are 10 dB farther away than ones above 22
> degrees (2000 miles vs 700 miles).
> 2) Splitting gain into circular polarization (Eggbeaters) loses 3 dB
> compared to incoming linear polarization
> 3) Small sats usually have linear antennas or, if they have cross
> polarization then even if they are RHCP when approaching, they may be LHCP
> going away, thus you still have a 50/50 chance of having a polarization
> mismatch, though having both polarizations will minimize most fades.
> 4) Most small Amateur sateliltes have less than 1W transmitters and simply
> cannot be heard on the horizon without several dB gain.
>
> My Conslusions are:
> 1) An Egg beater is ideal for STRONG satellites (Think ISS with 10 Watts).
> It will minimize fades horizon to horizon.
> 2) But there are NO, NONE, NADA current amateur satellites (not even the
> ISS right now) at that power level.
> 4) Hence an eggbeater even with a dB or so gain on the horizon simply is
> not going to hear anything until the satellite gets above about 20 degrees
> (when it is 10 dB closer)
> 5) So, why even bother with an eggbeater.
> 6) Use a simple 19.5" quarter wave vertical over a ground plane (for 2m).
> It will have 5 dBi gain above about 15 degrees (several dB better than an
> eggbeater).
> 7) and it will ALSO WORK even better as a 7 dBi gain UHF antenna (3/4 wave
> vertical) above about 25 degrees up to 70 degrees (6 dB better than an
> Eggbeater)...
>
> AND it is DUAL band as well! (on the same coax!)
>
> BUT, what about the donut hole overhead for these vertical antennas?
>
> Forgetaboutit.!.... The satellite is only above 70 degrees about 1% of
> the total pass times per day! And then for less than about 30 seconds!
>
> To visualize the orbit actual geometry see the scale plot on:
> http://aprs.org/LEO-tracking.html
>
> So, in my humble opinion, a 19.5" vertical whip antenna in the middle of a
> car roof (neat ground plane) will give pretty good satellite coverage. It
> will have some fades due to only one polarization, but the strong part of
> the cycle will be 3 dB stronger than it would be on a dual polarizatiaon
> antenna. And you don't have to be parked on a mountain. Since again, no
> omni antenna can hear these weak satellites on the horizon anyway, so as
> long as the trees are far enough away to give you sky above about 20
> degrees, you will have about the best coverage you can get for about a 20"
> of copper wire and a nice ground plane..
>
> In my opinion anyway.
>
> AND*** If you want to hear them all the way horizon to horizon, buy a $65
> TV rotator and attach a small 5 to 6 element beam tilted up at about 15
> degrees and hear them all! See above web page...
>
> Bob, Wb4APR
>
> -----Original Message-----
> From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of Devin L. Ganger
> via AMSAT-BB
> Sent: Friday, May 3, 2019 4:19 PM
> To: AMSAT-BB@?????.???
> Subject: [amsat-bb] ARRL Antenna book, eggbeater antenna designs
>
> Greetings, programs!
>
> I'm looking to work with my son (who will be studying to get his
> Technician license later this month) on building a UHF/VHF pair of
> eggbeater antennas. I've found a few papers online, but does anyone have a
> good reference to a detailed design?
>
> Does the ARRL Antenna book latest edition have any significant coverage of
> eggbeaters at all? I have an older version that has nothing.
>
> Also, most of the designs I see are for a single band. If you're deploying
> a pair for satellite operations, do you simply attach them through a
> duplexer? I have a Diamond MX-72N that I picked up a while ago for using
> with dual Baofengs, but it's been sitting in my drawer since I picked up
> my TH-D72A. It has a 1.6~150MHz lead and a 350~460MHz lead.
>
> Thanks in advance for any pointers you might have.
>
>
> --
> Devin L. Ganger (WA7DLG)
> email: devin@????????.???<????????????@????????.???>
> web: Devin on Earth<http://www.devinonearth.com/>
> cell: +1 425.239.2575
>
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available to
> all interested persons worldwide without requiring membership. Opinions
> expressed are solely those of the author, and do not reflect the official
> views of AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
--
David Johnson
------------------------------
Subject: Digest Footer
_______________________________________________
Sent via amsat-bb@?????.???.
AMSAT-NA makes this open forum available to all interested persons worldwide
without requiring membership. Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT member? Join now to support the amateur satellite program!
https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
End of AMSAT-BB Digest, Vol 14, Issue 179
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