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syadnom
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DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 12:21 am

I have a DISC Lite5 AC on a 20Mhz channel 5180 that wont get above 9dB output. It's connecting to an Omnitik AC and signal level is -71. Country is set to UnitedStates3 on both.

21dB antenna+9dB =30dB, but this is U-NII-1 so I have 42dB here. I should be able to get up to like 17dB on this device on this channel.

Any ideas?
 
Cablenut9
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 12:43 am

Try this:
/interface wireless set [find] antenna-gain=0
because your antenna gain is likely set to a gigantic number.
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 12:46 am

That did it
 
syadnom
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 1:04 am

well, it really didn't. I can lie about the antenna gain to get more output, but I shouldn't have to. I have 42dB available but I'm definitely limited to 30. If I set the gain to 21, I get 9dB output. 19 and I get 11dB. Is this an error in the U-NII-1 coding for UnitedStates3?
 
Cablenut9
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 1:16 am

well, it really didn't. I can lie about the antenna gain to get more output, but I shouldn't have to. I have 42dB available but I'm definitely limited to 30. If I set the gain to 21, I get 9dB output. 19 and I get 11dB. Is this an error in the U-NII-1 coding for UnitedStates3?
They don't know what you're using it for, so they give you 30 to be safe. That's why they let you change the antenna gain because they know you're going to use their equipment for a whole bunch of different things that they can't predict from thousands of miles away in Mikrotik HQ in Latvia.
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 7:53 am

The "united states3" country setting limits the EIRP of devices to 30dB. Could you please explain, where you're getting the 42dB figure from?
 
syadnom
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 6:25 pm

U-NII-1 in the US allows 4 watts (36dBm) EIRP for PtMP with up to 1 watt (30dB) output power with a declining output per gain over 6. So the 21dB gain on the disc means 21-6= 15 reduction off the 30dB so output should be able to go as high as 15dB. 21+15 = 36dB so the math all jives.

So why is UnitedStates3 limited to 9dB output when the rules allow for 15dB output?
 
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 6:35 pm

42dB ~ 16W !!!
where is coming that 42dB???

https://mikrotik.com/product/disc_lite5_ac

Wireless specification for DISC Lite5 ac is tx power max 25dBm @ 6MBit/s (22dBm for chain) and 18dBm @ MCS9 (15dBm for chain)
If you do not use "superchannel", you can't lie about antenna gain, if specified, are ignored: DISC Lite5 ac has integrated antenna with fixed 21dBi gain (18dBi for chain.

on "non-superchannel" max tx power is 9dBm (30dBm max - 21dBi), more appropriate: 6dBm for chain 0 and 6dBm for chain 1

the 30dBm max is defined inside RouterOS, use this command to check (in this example on 6.46.8 and 6.47.9)
/interface wireless info country-info "united states3"

ranges: 2402-2472/b,g,gn20,gn40(30dBm)
5170-5250/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(30dBm)/indoor
5735-5835/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(30dBm)/outdoor


but.. if the device can transmit to 25dBm (@6MBit/s) + 21dBi = 46dB... the device "Max power consumption" is 7W and transmit near 40W???...
I'm Italian, not English. Sorry for my imperfect grammar.
 
syadnom
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Re: DISC Lite5 AC 9dB only?

Fri Apr 23, 2021 10:37 pm

I’m not asking for 25dB output. I’m asking for the 15dB the FCC allows for PtMP with a 21dB antenna in unii1.

Also, I am able to set the antenna gain on the disc while being in regulatory domain and usa3 .
 
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Re: DISC Lite5 AC 9dB only?

Sat Apr 24, 2021 1:44 am

I’m not asking for 25dB output. I’m asking for the 15dB the FCC allows for PtMP with a 21dB antenna in unii1.

Also, I am able to set the antenna gain on the disc while being in regulatory domain and usa3 .

do not have read all what I have write?
starting from specific hardware and software version, antenna gain are IGNORED, do not matter if you can change the setting, if you use regulatory-domain on device with integrated antenna.
regulatory inside usa3, on mikrotik, is max 30dBm

open support ticket and provide link to official documentation for ask the unlock @ 15dB
I'm Italian, not English. Sorry for my imperfect grammar.
 
syadnom
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Re: DISC Lite5 AC 9dB only?

Sat Apr 24, 2021 1:54 am

What you are saying is flat wrong. I have multiple Disc5AC Lite units, fresh out of the box just installed a few days ago, running 6.48.2 with firmware to match and I can change the antenna settings no problem. With it at the default of 21, output is locked at 9. If I change it to 15 gain then the radio outputs at 15. The Omnitik AP also sees the increase in signal so this is actually happening, it's not cosmetic. If I change the antenna to 0, the radio screams out 30dB and modulation drops massively just like you'd expect. ie, the antenna setting is functional on new hardware on the most recent software and firmware.

No, the USA3 setting being locked appears to be true, but an error. This should allow 36dB in PtMP and 42dB in PTP in U-NII-1
 
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Re: DISC Lite5 AC 9dB only?

Sat Apr 24, 2021 2:05 am

With it at the default of 21, output is locked at 9. If I change it to 15 gain then the radio outputs at 15
screenshot of that?

first ac device to show output power on current tx power?
I'm Italian, not English. Sorry for my imperfect grammar.
 
syadnom
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Re: DISC Lite5 AC 9dB only?

Sat Apr 24, 2021 3:39 am

Here it is. No changes made to tx power. The 15dB output is a direct result of the antenna-gain=15. If I change gain to 14, output goes to 16 and so on.
disc_x.jpg
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