A difference that sometimes is not clear on spec sheets is you can't
have the same efficiency across all wavelengths. "5ghz" could mean from
4.9 to 5.8 (or more in some countries). The antenna won't be equally
effective across a whole ghz of spectrum.
You and I might test the same two dishes and you might say dish A was a
couple db better and I might say dish B was a few db better and the
difference might be that I'm using 5.1ghz and you're using 5.8ghz, so
we'd both be right about our respective dishes at our respective
frequencies. The spec sheet on both antennas might say "30dbi" and
they're both right because that's the peak gain at some point in the
5ghz band, but it needn't be the same point between the different
designs. The difference shouldn't be more than a few db so most of the
time we don't have to fret about it, but if you're looking for the
highest gain then it might matter.
------ Original Message ------
From: "Rory Conaway" <[email protected]>
To: "[email protected]" <[email protected]>
Sent: 1/23/2018 12:45:58 AM
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
So Chuck, what’s your opinion? Parabolic or reflector that the
manufacturers spec out at approximately the same gain?
Rory
From: Af [mailto:[email protected]] On Behalf Of Chuck McCown
Sent: Monday, January 22, 2018 8:16 AM
To:[email protected]
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
Gain of a parabolic reflector:
=10*LOG((0.55*((3.1415*Dia/Lamda)*(3.1415*Dia/Lamda))),10)
.55 is the efficiency factor. Most of them range between .55 and .60
Diameter is in inches. Lamda is in inches.
From: Rory Conaway
Sent: Monday, January 22, 2018 7:08 AM
To:[email protected]
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
If you are talking about the 2’ dishes, their gain in 5GHz is the same
as the KP reflector. We may test that but honestly, between the price
difference which is more than $100, the weight, and the complexity, it
would have to be significantly better and I doubt it is.
Rory
From: Af [mailto:[email protected]] On Behalf Of Mike Hammett
Sent: Monday, January 22, 2018 6:58 AM
To:[email protected]
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
They still work down there, just lose a couple dB. Their better
rejection makes up for it.
-----
Mike Hammett
Intelligent Computing Solutions <http://www.ics-il.com/>
<https://www.facebook.com/ICSIL>
<https://plus.google.com/+IntelligentComputingSolutionsDeKalb>
<https://www.linkedin.com/company/intelligent-computing-solutions>
<https://twitter.com/ICSIL>
Midwest Internet Exchange <http://www.midwest-ix.com/>
<https://www.facebook.com/mdwestix>
<https://www.linkedin.com/company/midwest-internet-exchange>
<https://twitter.com/mdwestix>
The Brothers WISP <http://www.thebrotherswisp.com/>
<https://www.facebook.com/thebrotherswisp>
<https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg>
--------------------------------------------------------------------------------
From: "Rory Conaway" <[email protected]>
To: [email protected]
Sent: Monday, January 22, 2018 7:57:40 AM
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
Most Jirous antennas aren’t good for under 5.4GHz though. We started
using them after being told more than 2 years ago they would have
updated nose cones shortly. I’m still waiting.
Rory
From: Af [mailto:[email protected]] On Behalf Of Mike Hammett
Sent: Monday, January 22, 2018 6:30 AM
To:[email protected]
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
Jirous makes antennas with good patterns.
-----
Mike Hammett
Intelligent Computing Solutions <http://www.ics-il.com/>
<https://www.facebook.com/ICSIL>
<https://plus.google.com/+IntelligentComputingSolutionsDeKalb>
<https://www.linkedin.com/company/intelligent-computing-solutions>
<https://twitter.com/ICSIL>
Midwest Internet Exchange <http://www.midwest-ix.com/>
<https://www.facebook.com/mdwestix>
<https://www.linkedin.com/company/midwest-internet-exchange>
<https://twitter.com/mdwestix>
The Brothers WISP <http://www.thebrotherswisp.com/>
<https://www.facebook.com/thebrotherswisp>
<https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg>
--------------------------------------------------------------------------------
From: "David Coudron" <[email protected]>
To: [email protected]
Sent: Sunday, January 21, 2018 9:04:56 PM
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
We love the KP Performance antennas for the CPEs, but haven’t used them
yet for backhaul. Have you been using them for that as well? We
were worried the wider beamwidth would catch too much other noise. Or
maybe that hasn’t been an issue?
Thanks,
David Coudron
From: Af [mailto:[email protected]] On Behalf Of Rory Conaway
Sent: Sunday, January 21, 2018 8:56 PM
To:[email protected]
Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
Right now the best antenna we have tested at 30dBi has been the KP
Performance antennas. We will be testing the RF Elements antennas
next.
Rory
From: Af [mailto:[email protected]] On Behalf Of David Coudron
Sent: Sunday, January 21, 2018 6:49 PM
To:[email protected]
Subject: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30
We have traditionally been using the Arc Wireless 30 dBi 5 GHz
parabolic dish for our shorter backhaul links when using 5 GHz. The
have been OK, but we have a tough time getting them and the radomes
from time to time. We are in that situation again. They are priced
quite competitively, and seem to do the job, however we are looking for
options since they are so spotty to get ahold of. We have messed
around with the Ubiquiti RocketDish for CPE connectorized radios, but
haven’t tried them out for backhaul as of yet. The specs appear to be
very similar and I expect they’d perform about the same other than the
N-Type vs SMA connectors. Anyone have experience with both of these
dishes? Or is there a better alternative that we should be looking at
in the $120 range (dish only)?
Regard,
David Coudron
