It is always peak gain. Check the return loss at the frequency you are interested in. If it is >10 dB you should be good.
From: Adam Moffett Sent: Tuesday, January 23, 2018 8:47 AM To: af@afmug.com Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30 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" <r...@triadwireless.net> To: "af@afmug.com" <af@afmug.com> 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:af-boun...@afmug.com] On Behalf Of Chuck McCown Sent: Monday, January 22, 2018 8:16 AM To: af@afmug.com 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: af@afmug.com 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:af-boun...@afmug.com] On Behalf Of Mike Hammett Sent: Monday, January 22, 2018 6:58 AM To: af@afmug.com 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 Midwest Internet Exchange The Brothers WISP ------------------------------------------------------------------------------ From: "Rory Conaway" <r...@triadwireless.net> To: af@afmug.com 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:af-boun...@afmug.com] On Behalf Of Mike Hammett Sent: Monday, January 22, 2018 6:30 AM To: af@afmug.com Subject: Re: [AFMUG] Arc Wireless 30 dBi vs RocketDish RD-5G30 Jirous makes antennas with good patterns. ----- Mike Hammett Intelligent Computing Solutions Midwest Internet Exchange The Brothers WISP ------------------------------------------------------------------------------ From: "David Coudron" <david.coud...@advantenon.com> To: af@afmug.com 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:af-boun...@afmug.com] On Behalf Of Rory Conaway Sent: Sunday, January 21, 2018 8:56 PM To: af@afmug.com 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:af-boun...@afmug.com] On Behalf Of David Coudron Sent: Sunday, January 21, 2018 6:49 PM To: af@afmug.com 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
