MR46E + ANT-3-A-B-C-D-E-F antenna gain fixed

[GIdenJoe]

Hi all,

Last few years multiple topics in this community were about the limitations on the MR46E's transmit power in combination with one of the MA-ANT-3 models.

example: https://community.meraki.com/t5/Wireless-LAN/MR46E-Too-low-2-4-Ghz-transmit-power-in-ETSI/m-p/150004

These antennas had in their specs the mention of a per-element antenna gain which caused Meraki dashboard to limit your transmit power even more below what we were used to.

Normally you just take your max allowed EIRP and subtract the antenna gain to reach your maximum Tx power.  However this per-element mention made it so that you had to subtract an additional 6dB on an MR46E which would put the max Tx power in Europe with a ANT-3-F6 to 2 maybe 3 dBm... 😉

I have recently noticed on a customer dashboard that this limitation has been removed and you now can treat the antenna gain again like any normal antenna.  So in the case of my example you can set the Tx power to 8 dBm instead of 2.  Also on the 5 GHz band you can now go way higher even on the channels that only allow up to 23 dBm.  No longer need to put the channels on 100 and higher to fix this.

[thomasthomsen]

And I was ,finally, just getting ready to drop those 5ghz numbers into that spreadsheet ( better late then never 🙂 ).

So I have to go test and measure again, is that what you are telling me ? 🙂

Is it from a specific version of software / dashboard it has been fixed ?

[GIdenJoe]

I believe it is a dashboard modification.  I'll have to test with another customer that has MR46E combinations.  Most of our customers are quite up to date with the MR software so I can't be 100% sure if there are any changes in the firmware that facilitated this.

I invite any customer/MSP's that manage MR46E's to test this out.

[thomasthomsen]

I have a nice "test spot", that I test all APs from, and I have all the old "survey data" from that spot as well. So when I get back into the office after easter, Ill do a new run with the same AP and settings to see if there truly is a difference.

[GIdenJoe]

I'm eager to read your findings 🙂

[thomasthomsen]

This is broken again (30.2).

My MR46 can only go to 12dbm again on 2,4Ghz with the default antenna.

On the other hand .... my MR36H can now go to .... 25dbm radio power on 5Ghz .... yes ... 25dbm .... wtf ... #broken.

(PS: And I just realised that the MR36H has a 6dbi antenna gain, so ... the EIRP would then be 31dbm ..... wauw ... just wauw ... )

[GIdenJoe]

You sure you selected the correct antenna?
ETSI 2.4 GHz = max 20 dBm EIRP

If it would be wrong and for example are using the default stubby dipole that has 3.8 dBi gain you would go no higher than 10 dBm Tx power, not 12 dBm.

[thomasthomsen]

Yes we agree that EIRP for 2.4Ghz is max. 20dbm.

But .... 3.8dbi + 12dbm = 15.8dbm EIRP - So where are the last , lets say 3db (rounding up/down) to the 20dbm max.

This is the classic problem with the MR46E

[GIdenJoe]

It's not the same problem.  The original problem added another 6 dB because the MR46E has 4x4 antenna design.  So you would have 20 - 6 - 4 = 10 dBm as max Tx power.  You mention 12 dB which is not the same issue.  Perhaps your antenna is not correct or the dashboard at least thinks so.

[thomasthomsen]

I thought then, mistakenly, that the original problem was that it would not go to a higher transmit power.  (I have an old post about that somewhere).

So it has never actually changed, its still only 12dbm radio transmit power with the normal "default" antenna. #sad. So I guess my old spreadsheet still applies.  

[AntonP]

Lots of mr46E & ant3-e6

I noticed that if you set the 5Ghz radio to a fixed channel, say 36 that you cannot set the transmit power of the MR46e & MA-ANT3-E6 higher than 11. As soon as you set the channel to 'Auto' you can suddenly (manually) set the transmit power higher. Up to a maximum of 18.

[GIdenJoe]

In ETSI area channels 36 - 64 only allow up to 23 dBm whilst channels 100 and above allow up to 30 dBm that is why you have the difference.