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Power Meter shows only 100mW from SR5

Posted: Thu May 25, 2006 5:25 pm
by surfnet
I have found the best tool I have ever seen for a WISP

This simple power meter allows you to see the output power of a card.. it can help you check cables, cards, and antennas.

Here is some startling info I found out.

I tested 5 SR5s and 5 Senao 200mW prism cards

Senoa Prism gave 200mW/24db output everytime excpet once. 1 card put 17db.. that card is now set aside as bad

SR5 .......100mW!!!!!!!!!!! max db is 20 and that is after setting tx-power to all fixed rates and then setting 30db!!!!!!!!!!!!!!!!!!!
this happens on all SR5!!!!!!
hello?? there is something wrong here.
I use mini-pci board with routerboard 14 4-min-pci -pci card. I read the specs and it says max power for each slot is 2.5watts.
We looked up the specs on the SR5 and did the math. You need 5.25 watts for full power. So I got got out my routerboard11 1mini-pci -pci card and it says it can do 5watts.
guess what?

only 100mw on those as well. I tested on other hardware platforms as well and still on 100mw of power. I would name the other hardware, but I dont want my post deleted. :(

I think there is a major problem here. I hope someone else can buy the power meter and do the same tests.

I think we really need to bang on this hard, I am looking for some kind of hardware that can support the full 400mw of the SR5.

I talked to my vendor who resells Sr5 and he said Ubiquity told them when they announced the cards that nobdy could support the power and that the motherboard companies would have to catch up.

The biggest problem I see is that I can get 200mw out of the prism card, but only 100mw out of the SR5. I would be happy for now for 200mw out of the SR5.

other than that the power meter is great for finding bad cables and pigtails and such. Since I have bought it and gone out to all my nodes, I have found and replaced ~10 cables. Some had much more loss than others.. some lost 10db!. But now that I can sit at the bench and test cables, I was able to replace the cables with known good ones. This has increased my performance alot. I can now get 10megs 5 hops out :)

Posted: Thu May 25, 2006 7:27 pm
by jarosoup
At what transmit rate did you test the SR5 radio at? You are aware that the transmit rate at 54Mbps is rated at 21dB +/-1 right? You might want to check with the spec sheet for this card and test each transmit rate (although power for 6-24Mb should be the same). Also verify that the card power settings are running as they should be.

Posted: Thu May 25, 2006 7:50 pm
by surfnet
Since I was not connected to anything. I assume the AP is beaconing its signal. That should be a 6mbps rate.. and should be full power

Posted: Thu May 25, 2006 7:51 pm
by surfnet
and remember that I tested the card with tx-power-mode at default and then I set the tx-power-mode to all fixed rates, and set the DB to 30

Posted: Thu May 25, 2006 11:05 pm
by jarosoup
I think Mikrotik would have to comment on if testing a beacon accurately reports the transmit rate power - I simply don't know. But, if there is no link for the radio to negotiate a transmit rate, it seems like your test may not be accurate...can anyone confirm this?

Also, setting your card to 30dB...this is 1 Watt. The maximum that card supports is 26dB. Perhaps this is causing some problems too?

Posted: Fri May 26, 2006 1:30 am
by surfnet
With the prism I get 24db in the same test. Also when I set it to 30db.. I first started at 14db and slowerly worked my way up. It was accurate to 20db..then as I raised the db above 20, the power meter never went above 100mW/20db

Another point is the power meter is designed to test the card, and it has a terminator on the other side for accurate measurments. So the meter is not supposed to be used when it is connected to a network.

Posted: Fri May 26, 2006 9:24 am
by normis
set it to default power and set it to use some frequency from 5.8Ghz, then it should do full power.

Posted: Fri May 26, 2006 10:48 am
by Equis
I have noticed even with Cm9 power does not shop up on the AP till dataflow

So when it first connects may be -90 but after a few mins go to -68

That may be the problem

Posted: Fri May 26, 2006 4:21 pm
by surfnet
I have set the power to default, and then I change it to all-fixed-rates.. ALso the power meter works in 5.8 , 5.3, and 2.4. I always change the frequency to 5785 before I start the test.
When it is default mode. It puts out 17db.

Posted: Fri May 26, 2006 4:44 pm
by surfnet
lets also remember a few things I said about

the routerboard14 states in the spec sheet that it on allows 2.5watts per card.
the routerboard11 states in the spec sheet that it allows 5 watts

The SR5 need 5.25 watts to run full power

when I put in a 2.4 prism card.. it runs at 24db /200mw or full power
this is in default mode

when I put it the SR5 in default mode. it runs at 17db/65mw
when I change the power mode to all-fixed-rates and then change the db. I can get it up to 20db/100mW

When I have the SR5 set as a station, it shows advanced-status in winbox. Which shows the db output range. it looks like this
6Mbps = 17dbm
9Mbps = 17dbm
12Mbps = 17dbm
18Mbps = 17dbm
24Mbps = 17dbm
36Mbps = 15dbm
48Mbps = 13dbm
54Mbps = 11dbm

here is another SR5 in the field
6Mbps = 19dbm
9Mbps = 19dbm
12Mbps = 19dbm
18Mbps = 19dbm
24Mbps = 19dbm
36Mbps = 15dbm
48Mbps = 14dbm
54Mbps = 13dbm

and here is a CM9 in the field
6Mbps = 12dbm
9Mbps = 12dbm
12Mbps = 12dbm
18Mbps = 12dbm
24Mbps = 12dbm
36Mbps = 10dbm
48Mbps = 8dbm
54Mbps = 7dbm

Now after testing lots of card I see that some card simply do not put out the correct amount of power.
I have seen a few prisms that put out 17db.. but I have yet to see any SR5 put out more the 20db.

I have ordered a new intel mb with 4mini-pci slots that states it has 18watts of shared power for the mini-pci..I should be getting that next week. Maybe that will change it ..

but the big fact remains that according to the Microtik specs showing 2.5 watts per mini-pci card on the routerbaord14, I think it is impossible to get full power, but what I do want is at least 200mw.. which I can see on the prism, so I know there is enough power for that.

Posted: Fri May 26, 2006 4:56 pm
by surfnet
here is info from the power meter site

The 802.11a specification uses OFDM modulation but also defines many other aspects of the signal. When an 802.11a device is not transmitting data, it will transmit short bursts (48uSec) of energy. These OFDM bursts contain four distinct regions resulting in a power envelope that is not constant with time. The bursts’ output power peak-to-average can vary as much as 8dB across the burst. The PM-2458 is designed to measure peak power, so what a user sees on the display of the PM-2458 is a power measurement that is quite a bit higher than the radio manufacturer’s power output specification (average power), as the meter samples these varying peaks. The meter will not display an average or constant power reading.

Posted: Fri May 26, 2006 5:16 pm
by jarosoup
Interesting. Have you tried this test with a fresh install where the SR5 is the only card the OS has "seen"? I have run into some random problems in the past with radios after swapping out different cards. Any chance you have access to a spectrum analyzer for that band?

FWIW, We're still using CM9 radios as we have seen too many issues posted about the SR2/SR5...they work great for some people, and not so well for others. We're still excited about the SR9 (if it ever comes out) as it will make some of our deployments a lot easier (and cheaper) but I fear these same issues will hinder their success due to the power draw issues :?

Posted: Fri May 26, 2006 5:49 pm
by surfnet
all my tests are done on the bench with the latest version of Mk in it, and only 1 card installed.

The db output (advanced status) I showed was from cards in the field in station mode

Posted: Fri May 26, 2006 5:54 pm
by Biggs
We did test a couple of SR5 with a spectrum analyser and did not get any reading above 21dB. The radios was transmitting at 6mbps and we did set the radio in aling mode so it was always transmitting. The cards was installed in a wrap and a RB532. Both was pumping out the same amount of power.

These numbers corroborates reading I made on some p2p link I have made with SR5.

Posted: Sat May 27, 2006 6:12 pm
by surfnet
has anyone even seen with a measurement tool, a SR5 in full power?

Posted: Mon May 29, 2006 9:08 am
by normis
like i said, it works at full power only in 5.8Ghz, it will decrease power in other frequencies. just like the specs say, it is a 5.8Ghz card.

Posted: Mon May 29, 2006 6:26 pm
by surfnet
on what platform do you get full power?
It clearly states on the spec sheet that the routerboard 11/14/18 cant support the power needed to run the SR5 at full power. I am looking on and I cant seem to find any spec that show the maximum watts the mini-pci slots can deliver for the RB532.

The only way I know the watt usage on the routerboard11/14/18 is that I just bought 3 from wisp-router and it came with a spec sheet. I also bought a routerboard532, that has not arrived, but I am hoping it will also give this detail.
Maybe since Mikrotik built the RB532 they could share the spec here and not make me wait for mine to arrive.

Posted: Mon May 29, 2006 6:34 pm
by surfnet
and one more thing..

I did tests in the 5.8 frequency, just like you said too. I dont even bother using the any other frequency.
Frequencies used for testing

and I was just looking for a spec that shows the SR5 using less power in other bands.. I cant find one,, can you perhaps post a link please?

Posted: Wed May 31, 2006 5:36 pm
by surfnet
So I received a Routerboard 532 yesterday and tested all my new SR5s on it and even though inside the winbox, it says it is 26db, the power meter on shows 21db.. and it jumps around alot.. from 20.5 to 21.8.

the prism cards on the other hand stay steady at 24db.

If I set the power to default on the SR5s it show 17db and remains steady at the level.

SR5 tests were done at 5805 and prism test were all done at 2.412

I am still awaiting my new 4-minipic intel motherboards that say they share 18watts among the mini-pci slots.

Also I can still find no specs on the power output of the mini-pci slots for the RB532.. anybody have that info?

Posted: Thu Jun 01, 2006 5:51 am
by BurstNET
<< I am still awaiting my new 4-minipic intel motherboards that say they share 18watts among the mini-pci slots. >>

interesting...what model # are these boards?


Posted: Thu Jun 01, 2006 6:30 am
by surfnet
model is gw2348-4 from

well. I got my boards today, and they are a bit different than I thought.. but still can be good.
They only have 16 meg flash on them. I thought since they had a compact flash slot that they would boot off that.. like a wrap board.. but they did not, and they are like the routerboards in the onboard flash.

you can get 32megs flash but you have to special order them, so I have to send mine back in order to get the other 16meg flash soldered on.

Posted: Thu Jun 01, 2006 9:00 am
by jober
Will RouterOS run on that board?

Posted: Thu Jun 01, 2006 3:43 pm
by stephenpatrick
That's an Intel IXP "X-scale" CPU board. No ROS support on that.
I have a couple of those with some other software running on them.
Performance is quite impressive but without a decent OS (and I mean RouterOS) it's not so useful. So they're sitting around unused.


CableFree Solutions

Posted: Thu Jun 01, 2006 4:27 pm
by surfnet
If I get the flsah up to 32 megs.. why wont the routerOS run on it?

Posted: Thu Jun 01, 2006 4:33 pm
by normis
If I get the flsah up to 32 megs.. why wont the routerOS run on it?
what do you mean? it does

about the power issues - RouterOS uses the values that are written in the cards EEPROM. if the results do not satisfy you, you can contact the manufacturer of the card.

Posted: Thu Jun 01, 2006 4:43 pm
by surfnet
will is run routerOS with 16 megs flash?

about the power issue
I am not saying the issue is a mikrotik one at all. I am saying it is an issue.

I was talking with our head engeinner about that very thing.. calling ubitquiti. I am just trying to get all the info I can.

In my opinion Mikrotik is the best thing since sliced bread :)

Every time I use other vendor, I see how much I really love MK. This whole power issues is stemming from 900mhz, The UB cards state they use 700mW.. I assume the power needed for that is very high.

I am testing the motorola 900mhz canopy and it works ok,, but everything else about it sucks!. I want to be able to use MK for 900Mhz and for that I think we will need very high power, that is, if UB every gets the SR9 ready for production.

Mikrotik routerOS= GREAT
Motorola BAM/Prism = CRAP!

Posted: Thu Jun 01, 2006 4:50 pm
by normis
just for the system package you need ~17Mb of space. So 32Mb would be the reasonable minimum.

Posted: Thu Jun 01, 2006 4:51 pm
by surfnet
great, then I after I send them back for more flash memory.. we shall see

Posted: Thu Jun 01, 2006 5:05 pm
by phendry
what do you mean? it does
Does it really?? The board in question is a Intel IXP42X based board which (like Stephen Patrick) I didn't think Mikrotik supported.

Posted: Thu Jun 01, 2006 5:13 pm
by normis
wait a second. i didn't write you anything about IXP, it is not supported. I just said that RouterOS can work on a 32Mb flash .

Posted: Thu Jun 01, 2006 5:15 pm
by surfnet
oh.. aw crap.. i guess they just go back then

Posted: Thu Jun 01, 2006 6:12 pm
by surfnet
What If I send 1 to you guys(Mikrotik), can you maybe work on making routerOS work on that processor?

Posted: Thu Jun 01, 2006 7:22 pm
by marksx
Try to test sr-5 with 5MHz channel bandwidth, there shold be more ;-)
I know that these 400mW is "marketing" but i don't care, that's about 6dB more than other cards, sometimes this can help a lot (form unstable -89 to -83)
And there is still option that your power meter isn't calibrated on all bands.
I've testes prism 2,5 mPCI and PCMCIA with HP spectrum analyzer and never saw 200mW, only demarctech 300mW model have about 180mW real world.
So do not take this results real, because that's only pointer, when you can see what happeneing with power.
I don't belive that expensive Rhode&Shwarz, HP or Anritsu power meters and spectrum analyzers cost that much because they are most famious brands...

PS. Have you dissasemble your sr-5's ?
There's one hardware method to power up card with direct 5V so the amp should give about 3-4dB more clean power
PPS. Which connector ? UFL/MMCX antenna-a or antenna-b ??
PPPS. Have you tested Tonze 684HA ?

Posted: Thu Jun 01, 2006 7:24 pm
by jober
Bet that's a BIG NO!
But it would be nice to have these boards for nstreme2 links.

Posted: Thu Jun 01, 2006 8:13 pm
by surfnet

can you give me a little more info on where to connect 5v on the SR5?

Posted: Thu Jun 01, 2006 8:19 pm
by marksx
not now, because i don't have one
But if you can make hi resolution photo i could help

my email (if you don't want to put this on forum) m.burzynski (at)

Posted: Fri Jun 02, 2006 9:32 am
by normis
What If I send 1 to you guys(Mikrotik), can you maybe work on making routerOS work on that processor?
sorry, IXP (intel Xscale) is a different architecture. We won't make a special RouterOS version for another architecture.

Posted: Fri Jun 02, 2006 1:46 pm
by marksx
sorry, IXP (intel Xscale) is a different architecture. We won't make a special RouterOS version for another architecture.
Have you tested performance of IXP 425 @ 533MHz ?

so the next routerboards'll be MIPS/x86 based only ?
if that's true we have only few IC's for routerboard left :

Au1550 (500MHz max)
MIPS 24K series (650MHz max)

X86 only intel mobile, almost full spectrum of performances, but design process will be very long, hard, and will cos wery big money.

Posted: Fri Jun 02, 2006 3:39 pm
by normis
so the next routerboards'll be MIPS/x86 based only ?
i didn't say that ...

Posted: Fri Jun 02, 2006 3:42 pm
by stephenpatrick
We tested IXP 425 533MHz with other (non-MT) software.
Actually the hardware is very impressive, with ethernet - wireless bridged throughput as fast as the best x86 platform, i.e. no CPU bottleneck.
however that software wasn't complete enough for us to use "for real", so it's left sitting in the lab.
Rigth now I think the only options are fast x86 platforms.
We have AMD "NX" fanless at 1GHz, which we demonstrated 200Mbps ethernet-wireless bridge throughput split between 5 radio interfaces, all running on a single box. A press release on our website if anyone likes that sort of thing
My take on it is this: If there is going to be no "port" of ROS to IXP platform, then optimised x86 with low-heat mobile processors is the way to go.


Posted: Fri Jun 02, 2006 4:15 pm
by marksx
Let assume that mikrotik'll bulid x86 based routerboard, AMD or Intel based, they won't be so cheap as 5xx series (all PCI bridges, BIOSes, 4-6 layer PCB's, expensive power supplies, high temperatures, etc etc) i think that price aobut 800USD /each will be minimum. If we have such big costs client's won't buy enough so probably price will rasie even more.
Design time for x86 can take years for medium company such as MikroTik (in this case big = Intel for example)
If we have simple procesor such as IXP-425 or Au1550 or MIPS 24K series
design will be extremaly fast and cheap. In one or two weeks is possible to project board, in next 1-3 weeks is possible to bulit prototype, and if software will be done in the same time and IF all will work fine, in 4-8 weeks you can bulid 10000pcs and we have routerboard 999999 series ;-)
for as low as 150-300USD ;-)
600MHz 24K series should be enough to transmit 70Mbps full duplex using dual nstreme.
But to be honest that way is dead-end, because all new processors are multicore, and without smp mikrotik won't be able to use 4-6 atheros with 100% their performance on one board.
I hope that new rb's will be relased soon, but that's only hope, because now is problem with buying 1xx & 5xx RB's...

Posted: Fri Jun 02, 2006 4:26 pm
by normis
i didn't say that either. broaden your view :)

Posted: Fri Jun 02, 2006 5:32 pm
by stephenpatrick
How to keep 10,000 Mikrotik users in suspense .....

... keep reading this thread ... :-)

Posted: Fri Jun 02, 2006 7:06 pm
by marksx
yeah probably 1934872969467 emails with question "when, how much, how fast"