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Is it safe to run standard Ubiquity 0.5a 24v poe injectors on modified sine wave inverters?

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WL7COO's picture
Is it safe to run standard Ubiquity 0.5a 24v poe injectors on modified sine wave inverters?

Van's auxiliary battery system has a 95 AH VARDA battery that usually floats @ 12.9 when the engine is off.  This is several tenths of a V higher than the AGM starting battery.  

Don't plan to make a habit out of this since either a  passive injector where cable runs are short or appropriate a step-up type passive injector powered by a large AGM battery charged from the aux battery's system or a solar panel on the roof will be the normal DC source for MESHMobile use.

Thinking about these inexpensive DC Power Point powered small inverters for 'field expedient' use or for impromptu demo purposes possibly in other vehicles.


Entirely different Question;
Whenever I attempt to enable tunnels  in I keep getting; 

Package update failed!    

Tunnel software needs to be installed"

When I search for 'Tunnel Software'  or 'vtun' on I do not find anything pointing at a package to load and I do find notes that state this software was included as of

Is this a known issue w/0b02 or  (more likely) have I completely missed something in some portion of the (very excellent) 'Help' file available in the 0b02 Setup page?

TIA, 73
...dan wl7coo


K6AH's picture
Tunnel - Package update failed!
The "package" loads from the AREDN server and therefore needs Internet access... either directly, or via a Mesh Gateway.

Andre, K6AH
WL7COO's picture
Thanks Andre, hoping to address that soon.

I'll be searching the forums to see how others got started with tunnels and probably working with Jason, KG6H to hook up to the Modesto Gateway initially.  
He and Ken,  KF6IDK are working steadily to effect AREDN connectivity to the North but  'tunnel to Gateway' is an experience I don't want to miss <g>.

I suspect tunneling to a Gateway provisioned with ADSL, all that is currently available in and around Mariposa,  will be relatively worthless and plan to support a Gateway at ADSL provisioned sites only when no better alternative is available. 

We're meeting with a modicum of success obtaining additional Mtn Top access for 'high level' connectivity.

The 'inexpensive inverters' did fine for about 8 hours on Sunday.  

The impact on voltage from the van's auxiliary battery (95AH)  was negligible, after 8 hours the battery's no load voltage was between .1 and .2 volts less than it was at the beginning, these are very efficient radios.  I'm going to have to make some way to put one of the DC 'Power Analyzers' between the battery and the POE source, be it passive or or inverted to AC for use with Ubiquiti injectors.  We know which will be more efficient but real power consumption for both methods on a 'per dbm power level' will be very useful data.

Are you aware of anyone using 'factory' 3GHz NanoBridge M3s?  
Are the radios identical to NSM3s or not?

TIA (again) & 73
...dan wl7coo


AE6XE's picture
Dan,  We've pulled off the
Dan,  We've pulled off the NBM3 from the reflector and used standalone on many occasions.   Also, putting an NSM3 on the reflector.     As far as I can tell, the NBM3 and NSM3 or identical just a different label on the package.     I've just not pulled the cover off to inspect to prove, but in practice can't tell a difference.

I suspect that we could also put a NSM5 or NSM2 on the NBM3 reflector and it will work fine.  

K6AH's picture
In the end it's subjective...

So here's my less than scientific analysis.  

The Ubiquiti spec for the NanoBridge M3 is Power = 25 dBm; Antenna gain = 22 dBi  

For the NanoStation, the spec is Power = 25 dBm; Antenna gain = 13 dBi

Assuming they are identical, and if you’ve mounted the radio correctly, you should expect about 9 dB in additional gain from the reflector.
When I pointed my NanoStation M3 alone directly at my Palomar Mtn node 26 miles away, I measured an SNR of 6 dB (with some variability up to as much as 9 dB).

When I mounted the NanoStation to a re-purposed DishNetwork reflector in approximately the same position as illustrated in the Ubiquiti spec sheet I measured an SNR of 15 dB (with some variability up to as much as 20 dB).

So it appears I achieved the theoretical maximum, 9 dB, gain from the reflector… and perhaps more when you consider the positive variability.

In the end, does mounting an NSM3 on a NB dish (or similar, as in my case) get you the gain you need?  Whether the NSM3 radio/internal antenna is identical to the NBM3 or not is really only interesting from a theoretical perspective.  My casual analysis suggests they could be.  But in the end, try it and see if it works well enough for you.

Andre, K6AH

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