UBNT seems to have focus groups... and then do the opposite of what they want.
----- Mike Hammett Intelligent Computing Solutions Midwest Internet Exchange The Brothers WISP ----- Original Message ----- From: "Ken Hohhof" <[email protected]> To: [email protected] Sent: Saturday, July 2, 2016 7:34:02 AM Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N So mechanical robustness and weatherproofing are not important on every other connectorized radio they sell? That explanation sounds fishy. Seems like the sort of decision you get when you are catering to a specific key customer. Or listening to a focus group. Oh wait, that’s what we are. From: Mike Hammett Sent: Friday, July 01, 2016 9:41 PM To: [email protected] Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N UBNT said that they went with N for its increased mechanical robustness and weatherproofing. Were they having issues with that at SMA? Why go cabled over waveguide at all anyway? ----- Mike Hammett Intelligent Computing Solutions Midwest Internet Exchange The Brothers WISP ----- Original Message ----- From: "Josh Reynolds" <[email protected]> To: [email protected] Sent: Friday, July 1, 2016 9:38:01 PM Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N Right, and so do the people you're talking about - keep it in mind they've already tested these. I brought up this exact issue by the way, when they (idiot customer) fuck up a connector and buy one from BillyBobs HAM shop and wonder why it doesn't work. I was told the cost on these was low, and they would be sold like any other connector or accessory. I mean, you DO buy spares for licensed backhaul, right? I was also told they are working on "other accessories" for this radio that will be some of the highest quality in the industry. On Jul 1, 2016 9:27 PM, "Chuck McCown" < [email protected] > wrote: Here is the thing, you buy a radio that has 11 or 18 GHz appearing on an N connector. Then you purchase a cable from your favorite cable place. Connect the two and wonder why you are having problems. If you get a cable that actually has connectors rated for the frequency if they did not sweep it, there is no guarantee it will work properly. And if they did sweep it it is going to cost a ton. SMA is cheap, easy and always works at those frequencies. N is only cheap and easy below 6 GHz. I am not saying a connector that is rated for the frequency will not do the job, but the connector is just the first step. If you do not use extreme precision at 18 GHz then sweep the cable with the proper gear it is going to have problems. Things like terminations at 18 GHz are not even trivial. It is so hard to get a good 50 ohm termination for calibration you generally use a sliding load. (Actually, you are normally using waveguide at 18 GHz. ) I do – do this for a living, you know... From: Josh Reynolds Sent: Friday, July 01, 2016 8:13 PM To: [email protected] Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N I'm saying the same thing. Take the connector designed for it, thrown your opinion in the trash, and post the results. Repeat the test. Have someone else repeat the test. Scientific method. On Jul 1, 2016 9:10 PM, "Chuck McCown" < [email protected] > wrote: <blockquote> Type N connectors are not in common use above 6 GHz. Believe me or not. You wanna go above 6, there are plenty of other cheaper and better connectors to use. N connector concentricity is not inherent to the design of the connector. And concentricity is essential to good return loss. You send me an N connector cable. I will put it on a load and connect it to a vector network analyzer with a smith chart on the screen. Will record video. Then I will wiggle the cable and back off the connector a bit you can see for yourself the dot (arc actually) wander all over the place. The higher the frequency the more it becomes a wild line. Then I will do the same for SMA and you can see for yourself which one is more stable. Opinions don’t matter. A dot is a dot, an arc is an arc and a squiggly line is a squiggly line. From: Josh Reynolds Sent: Friday, July 01, 2016 7:53 PM To: [email protected] Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N So, nothing personal by this... but if the connector is designed for it (and has several versions by other manufacturers to boot), has been used (and is still used) on testing equipment... I'm probably more inclined to take their word for it over yours. On Jul 1, 2016 7:58 PM, "Chuck McCown" < [email protected] > wrote: <blockquote> IMHO, 6 GHz is the upper limit. From: Peter Kranz Sent: Friday, July 01, 2016 5:22 PM To: [email protected] Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N “ Originally, the connector was designed to carry signals at frequencies up to 1 GHz in military applications, but today's common Type N easily handles frequencies up to 11 GHz. More recent precision enhancements to the design by Julius Botka at Hewlett Packard have pushed this to 18 GHz.” http://inmet.apitech.com/inmet/micro-inmet-between-typen.cfm Peter Kranz www.UnwiredLtd.com Desk: 510-868-1614 x100 Mobile: 510-207-0000 [email protected] From: Af [mailto: [email protected] ] On Behalf Of Chuck McCown Sent: Thursday, June 30, 2016 3:24 PM To: [email protected] Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N Yeah, I think this is a case of somebody bowing their neck - a pissing contest between a boss and underlings at UBNT. From: Eric Kuhnke Sent: Thursday, June 30, 2016 4:19 PM To: [email protected] Subject: Re: [AFMUG] Convert Andrew Dragonwave dishes to N I have never in my life personally seen an N connector rated above 11 GHz. High-quality/expensive N connectors are used extensively in two way satellite - such as with 3.0 meter C-band Tx/Rx earth station dishes... But you only use N for the 50 ohm coax cables from the modem (indoors) to the electronics which lives directly attached to the waveguide/feed on the dish (Rx LNB and Tx SSPA/BUC). The coax is used between 1.2 to 1.8 GHz to communicate with the Tx and Rx electronics on the dish. A satellite LNB on the Rx side is basically a 10:1 ratio downconverter. Like so: http://beta.satcomresources.com/sca/images/NORS3120N_detail-3.jpg There's your single polarity waveguide interface on one side, N on the other. On Thu, Jun 30, 2016 at 6:49 AM, Chuck McCown < [email protected] > wrote: <blockquote> First of all, I have never seen an N connector rated above 11 GHz, and those are extra expensive. If there is an 18 GHz version, it will be even more expensive. This will not be a cable you can make yourself in the field and it will be very sensitive to being fully seated so you will probably have to use a torque wrench to make it work at 18 GHz. Silly. You can weatherproof an SMA just as easy as an N connector. Good heatshrink can be found for both. Folks trying to use N connectors at 18 GHz are going to quickly get introduced to the world of return loss problems. Von: Af [mailto: [email protected] ] Im Auftrag von Rob Genovesi Gesendet: Donnerstag, 30. Juni 2016 01:32 An: [email protected] Betreff: Re: [AFMUG] Convert Andrew Dragonwave dishes to N >From Gary-UBNT: "We are working on data sheets right now so hopefully you will get more questions answered shortly. The reason for N connectors relates to demand for higher mechanical robustness and the ability for the connectors to be weather-proof as a stand alone connector (fully weatherproof gaskets and the ability to accept larger diameter jumpers readily). The N connectors we use are rated to 18+ GHz." An active thread on the UBNT forums right now, more available here: http://community.ubnt.com/t5/airFiber/Some-AF11X-details/td-p/1512145 -Rob On Wed, Jun 29, 2016 at 12:05 PM, Bill Prince < [email protected] > wrote: <blockquote> I'm looking at all the other AF-nnX radios from UBNT, and they all use SMA connectors. What reason would they have to use N instead of SMA? Seems the SMA connector would have fewer issues at 11 GHz. </blockquote> </blockquote> </blockquote> </blockquote>
