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draguzet
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Grid interference

Fri Jul 01, 2011 10:46 am

Hi !

We have one setup (antenas are on picture in attach):
RB 433AH
R52nM x 3

Problem is that when client or clients (1-2) are connected to Omni antenna, link that is on GRID antenna is degraded (from 40 Mbps to 5-10 Mbps). Frequency are 5850 for Omni, and 5300 for GRID, but no luck ?
DSCF9900.jpg
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Last edited by draguzet on Fri Jul 01, 2011 11:11 am, edited 1 time in total.
 
WirelessRudy
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Re: Grid interference

Fri Jul 01, 2011 11:06 am

550Mhz channel separation should be more than sufficient to stay out of interferences problems.
But what about other channels fm nearby AP's?
Or are the cards not getting too hot?

Show us your wireless settings (CLI: interface / wireless / export)
Start playing with freq's, and other wireless settings.
Many of us use two or more radio's in one box without problems. I have 6 AP's with similar setup (3rd card is 2,4G AP) and have 20 to 30 clients running and total throughput at times 20-25Mb...
 
draguzet
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Re: Grid interference

Fri Jul 01, 2011 11:23 am

550Mhz channel separation should be more than sufficient to stay out of interferences problems.
But what about other channels fm nearby AP's?
Or are the cards not getting too hot?

No nearby AP's, location are rural.

Show us your wireless settings (CLI: interface / wireless / export)
Start playing with freq's, and other wireless settings.
Many of us use two or more radio's in one box without problems. I have 6 AP's with similar setup (3rd card is 2,4G AP) and have 20 to 30 clients running and total throughput at times 20-25Mb...
I'm playing with wireless settings for 2 days, freq, N-only, A-only, Nstreme, Nv2...no luck.
I have on 2 location same situation, that client are 20 degrees left or right from GRID direction, and same problem that TX from Base station are not problem (40-50Mbps), but RX from client are disaster.


/interface wireless security-profiles
set default authentication-types="" eap-methods=passthrough group-ciphers="" \
group-key-update=5m interim-update=0s management-protection=disabled \
management-protection-key="" mode=none name=default \
radius-eap-accounting=no radius-mac-accounting=no \
radius-mac-authentication=no radius-mac-caching=disabled \
radius-mac-format=XX:XX:XX:XX:XX:XX radius-mac-mode=as-username \
static-algo-0=none static-algo-1=none static-algo-2=none static-algo-3=\
none static-key-0="" static-key-1="" static-key-2="" static-key-3="" \
static-sta-private-algo=none static-sta-private-key="" \
static-transmit-key=key-0 supplicant-identity=MikroTik tls-certificate=\
none tls-mode=no-certificates unicast-ciphers="" wpa-pre-shared-key="" \
wpa2-pre-shared-key=""
/interface wireless
set 0 adaptive-noise-immunity=ap-and-client-mode allow-sharedkey=no \
antenna-gain=0 area="" arp=enabled band=5ghz-onlyn basic-rates-a/g=6Mbps \
basic-rates-b=1Mbps bridge-mode=enabled channel-width=20/40mhz-ht-above \
compression=no country=croatia default-ap-tx-limit=0 \
default-authentication=yes default-client-tx-limit=0 default-forwarding=\
yes dfs-mode=none disable-running-check=no disabled=no \
disconnect-timeout=3s distance=dynamic frame-lifetime=0 frequency=5300 \
frequency-mode=superchannel frequency-offset=0 hide-ssid=no \
ht-ampdu-priorities=0 ht-amsdu-limit=8192 ht-amsdu-threshold=8192 \
ht-basic-mcs=mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,mcs-7 \
ht-guard-interval=any ht-rxchains=0 ht-supported-mcs="mcs-0,mcs-1,mcs-2,mc\
s-3,mcs-4,mcs-5,mcs-6,mcs-7,mcs-8,mcs-9,mcs-10,mcs-11,mcs-12,mcs-13,mcs-14\
,mcs-15" ht-txchains=0 hw-fragmentation-threshold=disabled \
hw-protection-mode=none hw-protection-threshold=0 hw-retries=4 l2mtu=2290 \
mac-address=00:0C:42:66:96:74 max-station-count=2007 mode=ap-bridge mtu=\
1500 name=wlan1_goli_Grid27 noise-floor-threshold=default \
nv2-cell-radius=10 nv2-noise-floor-offset=default nv2-preshared-key="" \
nv2-qos=default nv2-queue-count=2 nv2-security=disabled \
on-fail-retry-time=100ms periodic-calibration=default \
periodic-calibration-interval=60 preamble-mode=both \
proprietary-extensions=post-2.9.25 radio-name=xxxxxxxx \
rate-selection=advanced rate-set=default scan-list=default \
security-profile=default ssid=xxxxxxxx \
station-bridge-clone-mac=00:00:00:00:00:00 supported-rates-a/g=\
6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps supported-rates-b=\
1Mbps,2Mbps,5.5Mbps,11Mbps tdma-period-size=2 tx-power-mode=default \
update-stats-interval=disabled wds-cost-range=50-150 wds-default-bridge=\
none wds-default-cost=100 wds-ignore-ssid=no wds-mode=disabled \
wireless-protocol=nv2 wmm-support=disabled
set 1 adaptive-noise-immunity=none allow-sharedkey=no antenna-gain=0 area="" \
arp=enabled band=5ghz-onlyn basic-rates-a/g=6Mbps basic-rates-b=1Mbps \
bridge-mode=enabled channel-width=20/40mhz-ht-above compression=no \
country=croatia default-ap-tx-limit=0 default-authentication=yes \
default-client-tx-limit=0 default-forwarding=yes dfs-mode=none \
disable-running-check=no disabled=no disconnect-timeout=3s distance=\
dynamic frame-lifetime=0 frequency=5500 frequency-mode=superchannel \
frequency-offset=0 hide-ssid=no ht-ampdu-priorities=0 ht-amsdu-limit=8192 \
ht-amsdu-threshold=8192 ht-basic-mcs=\
mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,mcs-7 ht-guard-interval=any \
ht-rxchains=0 ht-supported-mcs="mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,\
mcs-7,mcs-8,mcs-9,mcs-10,mcs-11,mcs-12,mcs-13,mcs-14,mcs-15" ht-txchains=\
0 hw-fragmentation-threshold=disabled hw-protection-mode=none \
hw-protection-threshold=0 hw-retries=4 l2mtu=2290 mac-address=\
00:0C:42:66:96:78 max-station-count=2007 mode=ap-bridge mtu=1500 name=\
wlan2_Draguzeti_Panel noise-floor-threshold=default nv2-cell-radius=10 \
nv2-noise-floor-offset=default nv2-preshared-key="" nv2-qos=default \
nv2-queue-count=2 nv2-security=disabled on-fail-retry-time=100ms \
periodic-calibration=default periodic-calibration-interval=60 \
preamble-mode=both proprietary-extensions=post-2.9.25 radio-name=\
xxxxxx rate-selection=advanced rate-set=default scan-list=5180 \
security-profile=default ssid=Mladen_Sv.pavao station-bridge-clone-mac=\
00:00:00:00:00:00 supported-rates-a/g=\
6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps supported-rates-b=\
1Mbps,2Mbps,5.5Mbps,11Mbps tdma-period-size=2 tx-power-mode=default \
update-stats-interval=disabled wds-cost-range=50-150 wds-default-bridge=\
none wds-default-cost=100 wds-ignore-ssid=no wds-mode=disabled \
wireless-protocol=nstreme wmm-support=disabled
set 2 adaptive-noise-immunity=ap-and-client-mode allow-sharedkey=no \
antenna-gain=0 area="" arp=enabled band=5ghz-a basic-rates-a/g=6Mbps \
basic-rates-b=1Mbps bridge-mode=enabled channel-width=20mhz compression=\
no country=croatia default-ap-tx-limit=0 default-authentication=yes \
default-client-tx-limit=0 default-forwarding=yes dfs-mode=none \
disable-running-check=no disabled=no disconnect-timeout=3s distance=\
dynamic frame-lifetime=0 frequency=5850 frequency-mode=superchannel \
frequency-offset=0 hide-ssid=no ht-ampdu-priorities=0 ht-amsdu-limit=8192 \
ht-amsdu-threshold=8192 ht-basic-mcs=\
mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,mcs-7 ht-guard-interval=any \
ht-rxchains=0 ht-supported-mcs="mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,\
mcs-7,mcs-8,mcs-9,mcs-10,mcs-11,mcs-12,mcs-13,mcs-14,mcs-15" ht-txchains=\
0 hw-fragmentation-threshold=disabled hw-protection-mode=none \
hw-protection-threshold=0 hw-retries=4 l2mtu=2290 mac-address=\
00:0C:42:66:96:79 max-station-count=2007 mode=ap-bridge mtu=1500 name=\
wlan3_omni noise-floor-threshold=default nv2-cell-radius=10 \
nv2-noise-floor-offset=default nv2-preshared-key="" nv2-qos=default \
nv2-queue-count=2 nv2-security=disabled on-fail-retry-time=100ms \
periodic-calibration=default periodic-calibration-interval=60 \
preamble-mode=both proprietary-extensions=post-2.9.25 radio-name=\
Sv.Pavao_Omni rate-selection=advanced rate-set=default scan-list=default \
security-profile=default ssid=Sv.Pavao station-bridge-clone-mac=\
00:00:00:00:00:00 supported-rates-a/g=\
6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps supported-rates-b=\
1Mbps,2Mbps,5.5Mbps,11Mbps tdma-period-size=2 tx-power=9 tx-power-mode=\
all-rates-fixed update-stats-interval=disabled wds-cost-range=50-150 \
wds-default-bridge=bridge1 wds-default-cost=100 wds-ignore-ssid=no \
wds-mode=dynamic wireless-protocol=nv2 wmm-support=disabled
/interface wireless manual-tx-power-table
set wlan1_goli_Grid27 manual-tx-powers="1Mbps:17,2Mbps:17,5.5Mbps:17,11Mbps:17\
,6Mbps:17,9Mbps:17,12Mbps:17,18Mbps:17,24Mbps:17,36Mbps:17,48Mbps:17,54Mbp\
s:17,HT20-0:17,HT20-1:17,HT20-2:17,HT20-3:17,HT20-4:17,HT20-5:17,HT20-6:17\
,HT20-7:17,HT40-0:17,HT40-1:17,HT40-2:17,HT40-3:17,HT40-4:17,HT40-5:17,HT4\
0-6:17,HT40-7:17"
set wlan2_Draguzeti_Panel manual-tx-powers="1Mbps:17,2Mbps:17,5.5Mbps:17,11Mbp\
s:17,6Mbps:17,9Mbps:17,12Mbps:17,18Mbps:17,24Mbps:17,36Mbps:17,48Mbps:17,5\
4Mbps:17,HT20-0:17,HT20-1:17,HT20-2:17,HT20-3:17,HT20-4:17,HT20-5:17,HT20-\
6:17,HT20-7:17,HT40-0:17,HT40-1:17,HT40-2:17,HT40-3:17,HT40-4:17,HT40-5:17\
,HT40-6:17,HT40-7:17"
set wlan3_omni manual-tx-powers="1Mbps:17,2Mbps:17,5.5Mbps:17,11Mbps
17,9Mbps:17,12Mbps:17,18Mbps:17,24Mbps:17,36Mbps:17,48Mbps:17,54
20-0:17,HT20-1:17,HT20-2:17,HT20-3:17,HT20-4:17,HT20-5:17,HT20-6
:17,HT40-0:17,HT40-1:17,HT40-2:17,HT40-3:17,HT40-4:17,HT40-5:17,
HT40-7:17"
/interface wireless nstreme
set wlan1_goli_Grid27 disable-csma=no enable-nstreme=yes enable-poll
framer-limit=3200 framer-policy=best-fit
set wlan2_Draguzeti_Panel disable-csma=no enable-nstreme=yes enable-
yes framer-limit=3200 framer-policy=best-fit
set wlan3_omni disable-csma=no enable-nstreme=yes enable-polling=yes
framer-limit=3200 framer-policy=best-fit
/interface wireless align
set active-mode=yes audio-max=-20 audio-min=-100 audio-monitor=\
00:00:00:00:00:00 filter-mac=00:00:00:00:00:00 frame-size=300 \
frames-per-second=25 receive-all=no ssid-all=no
/interface wireless sniffer
set channel-time=200ms file-limit=10 file-name="" memory-limit=10 \
multiple-channels=no only-headers=no receive-errors=no streaming
no streaming-max-rate=0 streaming-server=0.0.0.0
/interface wireless snooper
set channel-time=200ms multiple-channels=yes receive-errors=no
 
sup5
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Re: Grid interference

Fri Jul 01, 2011 12:47 pm

have you got both wireless interface cards in ONE outdoor enclosure?

I strongly suggest one one wireless interface per metallic (shielded) outdoor enclosure, due to self interference issues.
 
draguzet
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Re: Grid interference

Fri Jul 01, 2011 1:16 pm

have you got both wireless interface cards in ONE outdoor enclosure?

I strongly suggest one one wireless interface per metallic (shielded) outdoor enclosure, due to self interference issues.
Yes, if I say that cards are on RB433, all cards are on same enclosure. Our experience is that this is not problem, problem is out of enclosure, not internal interference...and many many instalation are with 3 cards on same RB, and work ok.
Here is problem with interference on GRID, on my testing conclusion...
 
n21roadie
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Re: Grid interference

Fri Jul 01, 2011 2:52 pm

Looks like grid is using vertical polarity is the omni the same - if yes try horizontal for grid, also move if possible the grid down the pole a meter or so away from omni,
and seperate shielded enclosures for both antenna's,

And can you post from the current layout the interface\wireless - frequency scan from both antenna's
 
WirelessRudy
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Re: Grid interference

Fri Jul 01, 2011 3:26 pm

And can you post from the current layout the interface\wireless - frequency scan from both antenna's
Do the same for the clients, and print their configs as well.
 
SurferTim
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Re: Grid interference

Fri Jul 01, 2011 3:56 pm

I am going to side with n21roadie. That setup looks just like one of mine, except my grid antenna is turned 90 degrees and a foot down the pole. I would connect the grid mount post to the bottom of that horizontal beam. I don't use separate enclosures tho.

ADD: This was one of the best changes I think I've ever made to my equipment, and you can't see it with the box shut.
http://www.l-com.com/item.aspx?id=22584
That is why I use MMCX connectors on my radios.

EDIT: I won't step on the new post, but if it is like the light at my location, that light is HPS, and the transformer/ballast is at the base of the pole.
Last edited by SurferTim on Fri Jul 01, 2011 4:49 pm, edited 1 time in total.
 
n21roadie
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Re: Grid interference

Fri Jul 01, 2011 4:34 pm

[quote="SurferTim"]..... That setup looks just like one of mine, except my grid antenna is turned 90 degrees and a foot down the pole.....quote]
The polarity of your grid is horizontal, also just wondering about the light in the photo, is it fluorescent if yes would the starter choke cause RF, i cannot tell if the light is steel or alumimum or even ABS enclosure
 
WirelessRudy
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Re: Grid interference

Fri Jul 01, 2011 5:14 pm

Well guys, by all means, the location of the antenna's is not going to improve things for him. All your suggestions are valid, but imho not the issue in this case.

He has an 500Mhz separation of the channels which is plenty. I have a tower with 3 directionals, and one AP all in the 5500-5700Ghz range, all V-pol where the omni is actually tied to the back of a similar grid like on the photo and the whole tower is just 1,5 meters long! (I wouldn't do that any more, but hého.., this was done 6 years ago.... what did I know about interference at these days :o !)
I even have one duo antenna with ´n´ link running of that same pole and that just pumps 150Mbps tcp any moment of the day where the omni has 28 clients associated and running at the same time!
All these links and AP are fed from three plastic boxes only and the radios inside are thus actually bombarded with the signals from the directionals since they even at the not used radio connectors are scanned with -65 to - 70 levels! (Signals from the distant counterparts of the links)
Apart from an occasional disconnect due the NV2 issue we discuss elsewhere on the forum these links and AP all work fine for some years now....

If I take a good look at the info of draguzet, he runs a udp bandwidth test which is always very unreliable. His CCQ is absolutely crap. Both on the idle as on the load link.

He uses Nv2 while the signals are in the -71 range. NV2 doesn't like such low signal.
All conn. rates are set to default, he should start setting them to some fixed ones. Now all the radio is doing (due the bad signal level together with probable interference from other sides) is stepping up and down conn. rates so his throughput is completely destroyed.
He should start to look in arranging a proper link in the first place. I mean, 30Mb udp in one direction on a ´n´ link with NV2 while AP is idle is not a good result....

Although I don't know about the scan result for other freq. usage in his AP region and that of the clients and the other side of the backhaul, I can already see many parameters that have to be adjusted to get a proper link. (NV2 on a radio with default auth enabled is also asking for problems, now or in the future.)
But first thing I would do is to get the link signal towards the -65 at minimum. (Better aligning, bigger antenna on other side?)
 
n21roadie
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Re: Grid interference

Sat Jul 02, 2011 12:18 am

Well guys, by all means, the location of the antenna's is not going to improve things for him. All your suggestions are valid, but imho not the issue in this case.
Not sure about that, if he can reduce the signal pickup from omni ap to grid by seperating them as much as possible and using different polarity then maybe 10-20 db reduction is interference is possible?
But first thing I would do is to get the link signal towards the -65 at minimum. (Better aligning, bigger antenna on other side?)
While the picture has a nice layout it is not a workable solution, I would ask does the grid have to located where it is can it be repositioned, what is the distance the grid is covering and the ccq is not high enough,
 
mars
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Re: Grid interference

Sat Jul 02, 2011 1:38 am

put a metal cover on the back of the grid
 
WirelessRudy
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Re: Grid interference

Sat Jul 02, 2011 1:45 am

I still think it is not the AP or local interference causing the problem. It is a bad link from the grid towards its other end. He has to improve that link and than the omni becomes a small issue only.

Like I showed, two units close together but with 500Mhz separation is normally not giving any problems.
 
mike95826
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Re: Grid interference

Sat Jul 02, 2011 7:23 am

The first things to do is to separate the omni, the grid and the radio box. Move the radio box out of the main lobe of the omni by going down to about the level of the the cross brace. Use a metal enclosure if it is not currently. And be sure everything has a good ground. Slide the pipe that the grid is on down below the cross brace and get a larger solid dish. Too much RF around too small an area generates frequency mixing and other nasty things.
 
lazerusrm
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Re: Grid interference

Sat Jul 02, 2011 8:02 am

Here is how you fix it....

Switch to R52Hn's

Fixed.

:)

Some of the mikrotik hardware doesn't like to be near other devices, or in other words, require heavy isolation... No matter the frequency isolation, the input

filtering does not isolate enough, even if you have 500mhz separation i've still seen problems.

Devices i've tested and had poor results with (very) close proximity include

RB-711/711A
RB/SXT
R52Nm
Groove
Groove-A

R52Hn's on the other hand, seem to work great, even if the antennas are (near) touching they seem to work just fine, in my experience. I have less than 100 mhz separation. In fact, i have a short link that actually points directly through a separate antenna/radio, and it causes no interference, and the two
radios reside in the same enclosure. This particular site sees over 150 megabits constant bandwidth over 2 radios, 24/7.

Most of the Mikrotik devices will work fine if you get some decent isolation from each other. This can mean several feet, and some mesh in-between.

Your experiences may differ, but so far this is what i've seen. There also may be other cards that function well, like the SR71 series cards, and DBii F50-Pro.

But i have not tested these cards in this particular circumstance.

-Brad
 
n21roadie
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Re: Grid interference

Sat Jul 02, 2011 3:26 pm

Here is how you fix it....

Switch to R52Hn's

Fixed.

:)

Some of the mikrotik hardware doesn't like to be near other devices, or in other words, require heavy isolation... No matter the frequency isolation, the input

filtering does not isolate enough, even if you have 500mhz separation i've still seen problems.

Devices i've tested and had poor results with (very) close proximity include

RB-711/711A
RB/SXT
R52Nm
Groove
Groove-A

R52Hn's on the other hand, seem to work great, even if the antennas are (near) touching they seem to work just fine, in my experience. I have less than 100 mhz separation. In fact, i have a short link that actually points directly through a separate antenna/radio, and it causes no interference, and the two
radios reside in the same enclosure. This particular site sees over 150 megabits constant bandwidth over 2 radios, 24/7.

Most of the Mikrotik devices will work fine if you get some decent isolation from each other. This can mean several feet, and some mesh in-between.

Your experiences may differ, but so far this is what i've seen. There also may be other cards that function well, like the SR71 series cards, and DBii F50-Pro.

But i have not tested these cards in this particular circumstance.

-Brad
Are you saying the R52Hn's which is -3dB output of a XR5 (350 vs 600mw) solves the problem. this would indicate to me that either this radio card has a narrower receive bandwidth than the say XR5 or the output power which at -3db is half,
or both?

Have you tested XR5 cards,

I agree with you, position + isolation between Ptp's, Ap's and use any disadvantage which normally drives us nuts to our advantage like - any obstacle will attenuate the signal so by placing a mesh(or similar) between will reduce the signal but grids are not so easy because of the location of the dipole.
 
lazerusrm
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Re: Grid interference

Sat Jul 02, 2011 9:47 pm

I have not tested XR5's either in this scenario, unfortunately. Once you discover something that works well you use it, right? :)

I have tried all the devices listed above at low transmit powers to see if that would have diminish the effects of interference.

It does help to some degree, but it does not solve the problem. This would indicate to me that is has something to do with the receivers performance

characteristics. I will look into this further.

here are some screenshots

First picture is the scenario i mentioned above. It is an RB800 W/ 2 X R52Hn's. This unit works flawlessly. Never an issue. wireless uptime currently

greater than 30 days with no disconnects. Sorry i can't provide screenshots for this right now.

Its setup is as follows.

AP RB800 -> R52Hn#1 <--Wireless--> RB435G - R52Hn --PTP NV2
-> R52Hn#2 <--Wireless--> SXT SXT SXT SXT RB411/R52Hn PTMP NV2

Second two pictures are screenshots of what happens when you place an RB711 and a RB-Groove right next to eachother. Notice the disconnect as i did a

bandwidth test from RB433 -> RB711A, and then afterwards the reciever desensitized to -75 db (The First screencap was taken AFTER the bandwidth test)

Actual signal level is about -67 db. they are sparated more than 100 mhz. Also note, that the RB Grooves TX power is only 12db. the 711a is at full power

though.

Note: the Groove/711a link is currently up for my own personal testing and is not in production.

for clarification this particular test link is set up like this:

RB433 / R52Hn <--Wireless 20MHZ--> RB Groove/A <--Ethernet--> RB-711 <--Wireless 10MHZ--> RB-711a


Another note: The interference seems to diminish if you use smaller channel bandwidths, as would make sense. Noteworthy anyway!

You experiences may vary :)


-Brad
You do not have the required permissions to view the files attached to this post.
 
n21roadie
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Re: Grid interference

Sun Jul 03, 2011 3:54 am

I have not tested XR5's either in this scenario, unfortunately. Once you discover something that works well you use it, right? :)

I have tried all the devices listed above at low transmit powers to see if that would have diminish the effects of interference.

It does help to some degree, but it does not solve the problem. This would indicate to me that is has something to do with the receivers performance

characteristics. I will look into this further.

......................................

-Brad
I have tried to get unsuccessfully to get information about the receive characteristics of radio cards (http://forum.mikrotik.com/viewtopic.php?f=7&t=49835), while we know a radio card transmission characteristics has to comply with certain regulations the same does not apply in the receive cycle and this omission in data sheets by manufacturers makes the choice of radio card difficult in noisy environments.
 
WirelessRudy
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Re: Grid interference

Sun Jul 03, 2011 11:15 pm

Im¡ wondering how draguzet is getting along?
 
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Ibersystems
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Re: Grid interference

Mon Jul 04, 2011 12:36 am

Mmm

Try to move your box 1 meter down and try to use metal one if it doesnt work only moving it.

You have the back signal of the grid directly to your plastic box : O!
 
n21roadie
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Re: Grid interference

Mon Jul 04, 2011 1:14 pm

Also if draguzet had time to first do a frequency scan then paint with (Y-shield http://www.ecosorganicpaints.co.uk/stor ... rod_8.html) the inside of the plastic box storing the radio cards + board and then frequecy scan again to compare before and after signal results would be helpful for us to note the signal atteunation of it's use.
 
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Re: Grid interference

Mon Jul 04, 2011 1:39 pm

n21roadie, isn't easy to change the box for a metal one? instead of unmount the plastic one, remove the board, the pigtails, paint, wait for wet painting, mount the board, repair the broken rj45.. :lol: and cheaper!
 
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Re: Grid interference

Mon Jul 04, 2011 1:52 pm

n21roadie, isn't easy to change the box for a metal one? instead of unmount the plastic one, remove the board, the pigtails, paint, wait for wet painting, mount the board, repair the broken rj45.. :lol: and cheaper!
Correct but what i would like to know is how effective screening paint is in this case and especially where plastic cases are used my own issues with NV2 have such cases for AP's (viewtopic.php?f=7&t=49835),

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