I have recently added a remote 900AP to the existing 2.4/5.7 cluster. It recently locked up for no apparent reason. After I cold booted it the dbm reset to 28, as did all of the SMs. Initially the settings were 8. Any ever see this?
Also, I understand the dbm setting is supposed to match the db rating of the antenna, yet some remote customers service drastically improved after the change to 28 from 8-so I left it there. What are some of your experiences? Can this elevated dbm setting affect the SM’s transmitter?
skvelocity wrote: I have recently added a remote 900AP to the existing 2.4/5.7 cluster. It recently locked up for no apparent reason. After I cold booted it the dbm reset to 28, as did all of the SMs. Initially the settings were 8. Any ever see this?
Also, I understand the dbm setting is supposed to match the db rating of the antenna, yet some remote customers service drastically improved after the change to 28 from 8-so I left it there. What are some of your experiences? Can this elevated dbm setting affect the SM's transmitter?
There is no problem with running it at full power. The whole reason why the setting is there is so if you have a BIG antenna you can drop the power to stay withing FCC's EIRP regulations. Also, in some cases, you might want to drop the power if it's interfering with another one of your AP's.
What software version are you running? We originally had the field marked for antenna gain but now it has been changed to transmitter output power. So before you would put the antenna gain value while you now enter the output power.
We use 6.1.
I have 6.1, in this release it is the radio power you want.
So, for an antenna gain of 12dbi or less set it to 28.
This will give you max power within the fcc rules.
adamb wrote: I have 6.1, in this release it is the radio power you want.
So, for an antenna gain of 12dbi or less set it to 28.
This will give you max power within the fcc rules.
12+28 = 40; Is this legal?
micers wrote: [quote="adamb":294nax7l]I have 6.1, in this release it is the radio power you want.
So, for an antenna gain of 12dbi or less set it to 28.
This will give you max power within the fcc rules.
12+28 = 40; Is this legal?[/quote:294nax7l]
dBi != dBm.
dBi is decibels relative to an isotrope, dBm is decibels rel. to a miliwatt.
28 dBm is 630 miliwatts.
okconnect wrote: [quote="micers":3vqo5hoo][quote="adamb":3vqo5hoo]I have 6.1, in this release it is the radio power you want.
So, for an antenna gain of 12dbi or less set it to 28.
This will give you max power within the fcc rules.
12+28 = 40; Is this legal?[/quote:3vqo5hoo]
dBi != dBm.
dBi is decibels relative to an isotrope, dBm is decibels rel. to a miliwatt.
28 dBm is 630 miliwatts.
[/quote:3vqo5hoo]
The question I asked, was is 40 dB EIRP legal? I have experience with 2.4 GHz links and am familiar with the limits established for that portion of the spectrum. I don't have experience with 900 ISM and therefore am not familiar with the limits established for that portion of the spectrum.
I have "heard" that 900 MHz ISM is limited to 36 dB EIRP for all links both PtP and PtMP. That is why I asked the question. We have only just (last couple of weeks) installed a 900 MHz AP at 120' and are now studying it's capabilities. I have, to this point, operated under the presumption that I would be illegal if I deployed SMs with higher than 36 dB EIRP. Is that a correct presumption or does 900 ISM follow the same EIRP limitations in PtP links that the higher bands follow?
For the record though 28 dBm + 12 dBi is equal to 40 dB EIRP.
-m-
Well, yes I did say set it to 28.
However, I understand from the Canopy System User Guide that the actual max power is 26dbm ( even if you set 28 ).
Therefore 26 + 12 - 2 (for cable and connector losses) = 36 Spot on.
Which is, as you say and I understand, the max permissible EIRP
CANOPY SUPPORT - can you confirm max power in 26dbm?
adamb wrote:
Well, yes I did say set it to 28.
However, I understand from the Canopy System User Guide that the actual max power is 26dbm ( even if you set 28 ).
Therefore 26 + 12 - 2 (for cable and connector losses) = 36 Spot on.
Which is, as you say and I understand, the max permissible EIRP
CANOPY SUPPORT - can you confirm max power in 26dbm?
That is for the connectorized version or for all 900 MHz hardware. I was not trying to sharpshoot. I have not researched the limits. This thread was an opportunity to ask a pertinent question WRT the limits and the hardware as well.
Thanks
-m-
I think it is the same for both i.e. 26dbm.
I hope Canopy Support will confirm this.