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Has anyone tried these?

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WL7COO
WL7COO's picture
Has anyone tried these?

SecurAlign NSMReflector.

https://www.streakwave.com/itemdesc.asp?ic=NSMReflector&eq=&Tp=&o1=0

If it seems to good to be true ..........

If anyone has experimented with these and has formed an opinion, good, bad or indifferent, please share.
If it works to effect a more robust link at the edges of normal NSM ranges for an intermediate (mid-mile) link at less cost than a Rocket w/sector or dish with the advantage over a Rocket of an additional 100mbs Ethernet port - might be useful for frequency translation to/from another NSM freq.   

I'm thinking of 3GHz down to perhaps an NSM possibly running airOS as a largish 2.4GHz hotspot.  An extra few pounds and reasonable cost that might provide substantial utility for temporary deployments.

OTOH, if it seems too good to be true ......

TIA
...dan wl7coo

K6AH
K6AH's picture
Not equivalent to a RocketDish

i get the temptation... And it may work fine in your environment.  The shortcomings include: can't use RF Armor in RF competing environment; not as robust a package in severe weather environs.  Dollar per pound it can be the right solution.  In the M3 version it's a lot like the NanoBridge.  I'm playing around with a similar configuration using an old Dish Network reflector.  It definitely works.

Andre

kg9dw
kg9dw's picture
nanobridge M5

If you want a dish, use the nanobridge M5. Nice little unit for about $100 I've got 5 of them up.

http://www.neobits.com/ubiquiti_networks_nb_5g25_us_ubiquiti_nanobridge_...

They are getting harder to find.... We bought 10 of them off of ebay from a WISP that was upgrading. 

WL7COO
WL7COO's picture
Turns out the 3GHz NanoBridge is a Ubiquity version of the same

If they were the same price as the 5GHz NanoBridges I'd be all over them.

pax
...dan

KG6H
Nanobridge M5 range

KG9DW, What sort of range are you seeing with those NBM5's?

73, kG6H

kg9dw
kg9dw's picture
20km

I've got a 20 km link with nanobridges on each end that is used daily to provide data for a D-STAR repeater. Works great. 25-30 DB SNR. I have another link that shoots into the side of one of the dishes that I use to provide mesh access to my QTH. I'm hitting a side lobe of the dish 3km away...19DB SNR. It isn't the fastest link but it works great. 

We're also using an OMNI for an access point mesh node and then use the NBM5 nodes as end points (still mesh nodes, pardon the terminology). We've got one OMNI up and one dish up with 20DB SNR at 10km. I'd say this is the max distance I'd put a node hitting back to the OMNI. 

You can see the nodes (except for the node hitting the OMNI) on the beta map:
http://usercontent.aredn.org/K/5/K5DLQ/livemap.html

Look at Bloomington, IL. 

KE2N
KE2N's picture
reflectors

see  

http://community.ubnt.com/t5/NanoStation-and-Loco-Devices/Install-a-NanoStation2-LoCo-on-Reflector-How/td-p/189323

Within this discussion chain you will see the internals of the loco and the full nanostation.
The full nanostation has two patch antennas.  Only one of them can be at the focus of the dish.
So the technical basis for boosting the loco is better than the full nano.
But then if you are trying to reach long distances, why are you using a loco (rhetorical question)?





 

KG6JEI
While there are two elements,

While there are two elements, I belice they should be part of a phased array and as such have a focal point that is combined between the two of them as at that point it bevokes one antenna. What that exact position is I can't say for sure but it should be no different than stacked beams where they still all aim
to one location or repeater antennas that are 5/8 over 5/8 it creates on generic pattern.

I am not an antenna design expert however so could be wrong on this.

kg9dw
kg9dw's picture
A better example may be a

A better example may be a Dish network antenna, where there are multiple LNBs mounted at the focal point. Sure, they aren't all at the exact focal point, but they are close enough to achieve the designed gain requirements. It's also neat how these dishes don't have the LNB located at the focal point in order to prevent shadowing of the reflector surface. 

A trip through google searches brought me to an interesting observation. While gain certainly varies by frequency on these dishes, the focal point does not change. 

Here's a good backgrounder by N1BWT:
http://www.qsl.net/n1bwt/chap4.pdf
 

KE2N
KE2N's picture
seeing double

I believe the multiple LNB's are arranged to point at different satellites - which are in different points in the sky in the geosynchronous orbit "belt" -  the satellites are effectively in a line.  You could say the antenna has more than one boresight.

If one got really clever, a horizontal nano-station/parabola antenna could be used for two point-to-point links ... if the two stations were in exactly the right orientation  ;-)

 

KE2N
KE2N's picture
feed point

The feed for a parabolic dish needs to be a "point source" for perfect results. Of course, all real-world antennas are bigger than a point, but dish feeds are generally designed to concentrate their radiation into as small an area a possible. A single patch is already a bit large. Many parabolic dish antennas use a "horn" type of feed (Ubiquiti dishes do).  

To stretch the analogy with stacked beam antennas - the stacked beams have two reflectors. Here we have only one reflector. It can only be located properly with respect to one of the patch antennas.  And location of the feed point relative to the focus of the dish is rather critical. If you manage to get both patches at the right focal distance simultaneously, they will each have a different "boresight".  Assuming a vertical orientation, that means you will have one beam on the horizon and the other beam either up at the sky or down on the ground. 

Paul Wade (W1GHZ) has written some very readable material on this subject. 
table of contents
http://www.w1ghz.org/antbook/contents.htm

 

zl4dk
zl4dk's picture
Yes all real feed antennas

Yes all real feed antennas are larger than a point source but there is an imaginary point slightly behind the real antenna that the energy appears to come from. It is this imaginary point that needs to be set to the focus point of the dish. For an antenna that is rectangular (such as a Nanostation) the imaginary source in the horizontal plane may be at a different point to that of the vertical plane. Therefore for a normal parabolic dish it would not be possible to have both aligned simultaneously, however this could be used to give an antenna that had a narrow beam in one plane and a wider beam in the other (like a sector antenna). Alternatively the dish could actually be constructed to have it's focus in one plane slightly longer than in the other.

K7OPA
K7OPA's picture
legal?

I have seen discussions on the UBNT forum saying that the reflectors are not legal per FCC, in a commercial environment.  I assume there are no issues with using them in ham spectrum (EIRP, etc.) - anyone familiar with that?

KG6JEI
I can't say that I know the

I can't say that I know the direct thread you are referring two but I can think of a couple Part 15 regulations (Modification of a radio Device, use of an unapproved antenna [the reason RP-SMA was used for wifi], or exceeding EIRP. All of which can affect Part 15 users but have zero on us as Part 97 operators who have different regulations to comply with which while they exist are much looser.  

I would be much more worried about RF exposure on these bands than I am about max legal output power as exposure is very easy to get into the danger zone.  (You shouldn't put your hand directly in front of a NanoStation at full power as IIRC the Part 15 filing called out MPE distance as at least a few inches away )

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