I"m have a test system setup:

a rb 532 w/ nmp 8602 card to a 5.5 db rubber ducky omni.

to

a RB112 which has 2 nmp 8602 cards in it (I'm going to use these things as repeaters and are what im testing here.)

The 532 is just an access point for my cable line, for my house. AP-Bridge, DHCP server, Masq Nat.

I have the rb 112 set on wlan 1: as station and wlan2: ap bridge with its own dhcp-server.

everything works great, i can connect any of my 4 laptops to the WLAN2 of the repeater and surf/ping GW just fine.

the only issue / question i have is why when both sides show -50 signal, bw test 10mbits up or down to each other, -99 noise floor, have a disconnect every hour or so.

it reconnects just fine, its just i have laptops connected to this Access point that will stack up 10s of days of uptime, and this radio to radios setup, with MUCH better signal strength cant even keep up an hour?

as for the log messages, its honestly every type of wifi disconnect: reassociating, no beacons, decided to deauth: group key handshake timeout. different things different timies.

any ideas? both sides are MT 2.9.3 (host) and 2.9.26 (rb112)

EDIT: I'm not using WDS, since i used to have a WDS connection in the field and it would never be stable...(this is different equpiment btw.)

tks

Replace that RB112 with an RB532 and try again.

thats alot more $ AND the 532s dont work with the nmp-8602 really

i turned on NStream on both sides and the connection has stayed connected for 2 days now..and alot more bandwidth via tests.

The only issue is i can do this bc, this device is used as a repeater, thus NStream can not be used on the host end..

why it wont stay connected in station mode?

rb532's work with 8602's a lot better than a rb112 will. Go read the specs for the power available on each RB, then read the specs for the max power required for a single 8602. You're lucky you haven't burned out the voltage regulater on that rb112, and it sure isn't going to be stable.

You can have it cheap or you can have it right, pick one.

The RB112 can easily provide enough power for a single SR2, SR5, SR9, and NMP-8602+
And there has been known issues with some NMP-8602+ and RB532s, just search the forums.
I have for example had NMP-8602's that causes an RB532 to reboot whenever its at 5ghz but they work fine in RB112s. As a rule I only use SR5s whenever operating at 5ghz.

As far as the disconnect issues in my testing I have been able to repeat odd disconnect behariour by a few different methods.

1. Interference - I have had a customer with a baby monitor knock both his internal wireless off and his CPE off. Whenever he turned it off or on it would pulse across the entire spectrum and disrupt the signals long enough for it to cause a disconnect. His signal strength was -52. I've had the same issue with numerous poor quality 2.4Ghz phones.

2. Good speed, good signal, but antenna is getting reflections off of other objects - A good example of this was a problem I was having with wireless inside a customers house. He was using a new type of insulation on his outer walls that was lined with foil, and he had a metal roof put on. Speeds were great, signals were excellent, but every 2-3 hours all his computers would disconnect for approx 5-10 mins then all reconnect. The issue was that the signals could not 'escape' his house and would just continue reflecting and bouncing around until there was so much old RF 'noise' that the connection would not stay stable. Once all the computers disconnected and stopped transmitting, the old RF 'noise' would slowly dissipate during the 5-10 mins that the process would start all over again.

thats true regurading noise...but here is why i think that is flawed:

I have 4 laptops that are in further parts of the house and they are generally plugged into electical sockets and will rack up DAYS and DAYS of wifi uptime as read @ the MT box......while the RB112 in Station mode will only last 5-30min.

. reguarding the nmp 8602:

I have TONs of experience with these cards.. TWO 8602s will work fine on RB 112s...

532s will give you tons of random problems with the 8602..read around i have a huge thread on the 532 + 8602 where eugnene finally admited there is a 8602 / 532 specific issue....

infact if i have a card that causes the 532 to continously reboot i will use a rb 112 to reset the cards or set the settings to what i want, then put it back in teh 532 and it will work fine...as long as i dont change any settings

jo

2. Good speed, good signal, but antenna is getting reflections off of other objects - A good example of this was a problem I was having with wireless inside a customers house. He was using a new type of insulation on his outer walls that was lined with foil, and he had a metal roof put on. Speeds were great, signals were excellent, but every 2-3 hours all his computers would disconnect for approx 5-10 mins then all reconnect. The issue was that the signals could not 'escape' his house and would just continue reflecting and bouncing around until there was so much old RF 'noise' that the connection would not stay stable. Once all the computers disconnected and stopped transmitting, the old RF 'noise' would slowly dissipate during the 5-10 mins that the process would start all over again.

Please do not spread this garbage. It is not true. Other users do not take this gospel as science.

2. Good speed, good signal, but antenna is getting reflections off of other objects - A good example of this was a problem I was having with wireless inside a customers house. He was using a new type of insulation on his outer walls that was lined with foil, and he had a metal roof put on. Speeds were great, signals were excellent, but every 2-3 hours all his computers would disconnect for approx 5-10 mins then all reconnect. The issue was that the signals could not 'escape' his house and would just continue reflecting and bouncing around until there was so much old RF 'noise' that the connection would not stay stable. Once all the computers disconnected and stopped transmitting, the old RF 'noise' would slowly dissipate during the 5-10 mins that the process would start all over again.

Please do not spread this garbage. It is not true. Other users do not take this gospel as science.

Not the best explanation. Multipath without diversity (Gee, what are those other connecters for?) does cause some interesting events.

Mike

-50 is too strong a singnal for the radios sensitivity.
Try lowering your output power.

My 'garbage' is easily proven. Take a spectrum analyzer, a few wireless devices, an AP, put them in a some completely RF sealed room and watch what happens on the SA. Just because I used a 'real world' example does not mean I didn't look at the science behind it.

This is not really a multipath problem, multipath refers to how the 2.4ghz propagates from radio to radio. And yes that can be a problem as well, however this problem has to do with the amount of background noise that is generated over time.

For example when radio A transmits to radio B, and after radio B has acknowledged the receit of the transmission, where does that radio wave go. It doesn't stop dead, it will keep bouncing around until the microwave energy has become so low you can consider the wave 'dead.' In most cases the wave will bounce away or into materials that absorb the energy, thus killing the signal fairly quick, but in some cases for example in small area that is effectively rf sealed. The signals can remain around long enough to start causing background noise problems.

I have done both extensive research and 'real world' testing to prove this. If you don't believe me fine, these forums are for helping and I am just suggesting something that 'could' be causing a problem.

Radio energy dissipates within microseconds and does not build up after time. Otherwise should keep the microwave oven closed for an hour after you heat your hungry man dinner to keep from frying your eyeballs.

Radio energy dissipates within microseconds and does not build up after time. Otherwise should keep the microwave oven closed for an hour after you heat your hungry man dinner to keep from frying your eyeballs.

Except that your hungry man dinner absorbed the microwaves - that's why it's hot!

And, after all - after waiting for an hour before opening your micro wave, you could just start it all over again, as your hungry man dinner will be cold again after that hour.

Best regards,
Christian Meis

hungry man dinner

i have similar problem with
[configuration1]: SR9 rb112 and 8km link with no line of site. signal strength is 85-87dBm but we have no link actually. the station and bridge sit connected all time, but ping is bad. noise floor 97, 2427 2GHz-10MHz, antennas 15dBi yagi.

best regards,
C. G.

IMHO On all my 532ap+SR9 to 112+SR9 clients, I must have at least a -70 link before I will even consider it stable, Even at that strength I am losing association if the noise floor drops down to -85 from its normal -95. The best investment I have made is noise filters. They do help, but the links will still drop for a split second from time to time.

Noise filters? Where do you purchase, and do you only place these on the APs, or at each station suspected of having interference issues?

IMHO On all my 532ap+SR9 to 112+SR9 clients, I must have at least a -70 link before I will even consider it stable, Even at that strength I am losing association if the noise floor drops down to -85 from its normal -95. The best investment I have made is noise filters. They do help, but the links will still drop for a split second from time to time.

hi there,

i'm affraid, i don't know what is noise filter actually.
can u more recently introduce?

kind regards,
C. G.

http://www.titanwirelessonline.com/Sear ... sp?Cat=110

Here you go, I dont know who else sells them.

They did work for me, I have puchased three of them.

http://www.titanwirelessonline.com/Sear ... sp?Cat=110

Here you go, I dont know who else sells them.

They did work for me, I have puchased three of them.

did you put a filter at the AP? or at the client? or both sites?

regards,
C. G.

[quote="chvdr"]i have similar problem with
[configuration1]: SR9 rb112 and 8km link with no line of site. signal strength is 85-87dBm but we have no link actually. the station and bridge sit connected all time, but ping is bad. noise floor 97, 2427 2GHz-10MHz, antennas 15dBi yagi.
quote]

hey! we lift up the antenna 2m in the air and change channel to 2437 & we have good-ping, but super-low-bandwith link. noise floor 99, signal level -79 to -89 <very instable, a? ':?'> ccq tx/rx=5-25/5-25.

is it possible we have prob because of eoip-tunneling and bridging in the same routers, 112 both sites.

and i wonder, is it possible a link with sig. strenght -80 (even -89) be so unstable? Or we made smt. wrong... we looking just for a link with 1.5-2Mbps, nothing more...

regards,
C. G.

i have similar problem with
[configuration1]: SR9 rb112 and 8km link with no line of site. signal strength is 85-87dBm but we have no link actually. the station and bridge sit connected all time, but ping is bad. noise floor 97, 2427 2GHz-10MHz, antennas 15dBi yagi.

hey! we lift up the antenna 2m in the air and change channel to 2437 & we have good-ping, but super-low-bandwith link. noise floor 99, signal level -79 to -89 <very instable, a? ':?'> ccq tx/rx=5-25/5-25.

is it possible we have prob because of eoip-tunneling and bridging in the same routers, 112 both sites.

and i wonder, is it possible a link with sig. strenght -80 (even -89) be so unstable? Or we made smt. wrong... we looking just for a link with 1.5-2Mbps, nothing more...

and i think

IMHO On all my 532ap+SR9 to 112+SR9 clients, I must have at least a -70 link before I will even consider it stable, Even at that strength I am losing association if the noise floor drops down to -85 from its normal -95. The best investment I have made is noise filters. They do help, but the links will still drop for a split second from time to time.

it's a bit stupid to waiting to see -70dB link and then expect to work stable... sr9 must work with absolutely no line of site...


regards,
C. G.

I put the filter at the AP only.

And as far as "Stupid" My Links work perfect since the filter at AP.

So good luck

I put the filter at the AP only.

And as far as "Stupid" My Links work perfect since the filter at AP.

So good luck

thanks, is that the only one we have to make (put noise filter on AP site)? U said your link is -70, our - -80 - -88 now.

regards,
C. G.

I put the filter at the AP only.

And as far as "Stupid" My Links work perfect since the filter at AP.

So good luck

thanks, is that the only one we have to make (put noise filter on AP site)? U said your link is -70, our - -80 - -88 now.

regards,
C. G.

Almost all of the noise I see is at the AP, So that is why I placed a filter there.

Almost all of the clients I have see very or little noise, so no filter.

My experience thus far has seen that if I have a client connected at or above -80 , and if I try to pass data thru the link the link will drop off line.

So as a general rule I try to get all my clients to a -70 to-74 to even think about it being stable.
I hope this helps.

What is your noise floor level?

. . .
. . .

What is your noise floor level?

-99 or -98. depends of the time of the day. now we replace antenna at the client's site, new one is 2dBi more.
now we have signal -72 to -80 and the same problems.

Try to learn something about physics, it is total nonsense. I study math and physics on university so I have some knowledge about this.

2. Good speed, good signal, but antenna is getting reflections off of other objects - A good example of this was a problem I was having with wireless inside a customers house. He was using a new type of insulation on his outer walls that was lined with foil, and he had a metal roof put on. Speeds were great, signals were excellent, but every 2-3 hours all his computers would disconnect for approx 5-10 mins then all reconnect. The issue was that the signals could not 'escape' his house and would just continue reflecting and bouncing around until there was so much old RF 'noise' that the connection would not stay stable. Once all the computers disconnected and stopped transmitting, the old RF 'noise' would slowly dissipate during the 5-10 mins that the process would start all over again.

Try to learn something about physics, it is total nonsense. I study math and physics on university so I have some knowledge about this.

I am confused what you are saying?

You contributed nothing to this forum discussion.
I am trying to help someone workthough a problem they have been having.

As you have a physics and math background you should understand that there is no easy calcuation for exact microwave energy dissipation. It is a per site type of calulation with many factors. Most equations you will find, are an approximation as to when the radiated energy is so low that it is essentially zero. BUT it is not zero, so saying it can have NO effect is ignorant. Every situation is unique, my experitise is not in radiowave mechanics, but I did have an overview of it when I studied in university, some of my reasoning my be flawed through the same ignorance you are showing, but the results and outcomes, as well as my solutions may still be helpful to others on this forum. If you want to contribute and 'correct' my reasoning, while still explaining the situations myself and many other come across, I would welcome that feedback.

Please trust me (and not only me) that microwave energy cannot last reflecting again and again for more than a few miroseconds in some real situation in a house. Realize that majority of common materials absobs microwave energy, so even if you would have perfecty reflecting walls, it is still not enough. It is just not possible to accumulate microwave energy in some house like you wrote. What would happen if you would turn on microwave oven without anything in it? If it would be as you said, microwaves should stay inside for some minutes, which is really funny idea

You contributed nothing to this forum discussion.
I am trying to help someone workthough a problem they have been having.

As you have a physics and math background you should understand that there is no easy calcuation for exact microwave energy dissipation. It is a per site type of calulation with many factors. Most equations you will find, are an approximation as to when the radiated energy is so low that it is essentially zero. BUT it is not zero, so saying it can have NO effect is ignorant. Every situation is unique, my experitise is not in radiowave mechanics, but I did have an overview of it when I studied in university, some of my reasoning my be flawed through the same ignorance you are showing, but the results and outcomes, as well as my solutions may still be helpful to others on this forum. If you want to contribute and 'correct' my reasoning, while still explaining the situations myself and many other come across, I would welcome that feedback.

Please trust me (and not only me) that microwave energy cannot last reflecting again and again for more than a few miroseconds in some real situation in a house. Realize that majority of common materials absobs microwave energy, so even if you would have perfecty reflecting walls, it is still not enough. It is just not possible to accumulate microwave energy in some house like you wrote. What would happen if you would turn on microwave oven without anything in it? If it would be as you said, microwaves should stay inside for some minutes, which is really funny idea

This thread reminds me of an old joke I heard in college some decades ago:

Professor is isimultaneously nterviewing two graduate students (one majoring in math, one majoring in physics) to decide which to appoint.

The professor said "At the end of the hallway, you see a beautiful young lady who will do whatever you ask if you approach her the right way. Her way is for you to halve the distance with each step towards her."

The graduate student in math replied "There's no use in continuing this interview --- I'll never get there by halving the distance with each step."

The physics major said "I can get there for all practical purposes."

`[8-))

best regards/ldv

This is kind of odd but i heard the exact same "radiowaves got caught in a house" scenario when i started working in Moss, Norway. He (the radio expert) was just testing me to see if i had a firm grip on physics or if i was over-analyzing the problem to see if i would reason an impossible scenario into a possible one.
It's kind of intriguing how that exact scenario shows up again.

I believe "self inflicted noise" can be a problem in some scenarios, as i am no radio, expert but the explanation offered for the radio sealed house scenario is, as far as i know, incorrect.

ldvaden, I am not disagreeing with what you said. Microwave should indeed dissipate very quickly in a typical house, if it didn't we would have major issues. Every object on earth does have some degree of microwave absorbtion and even a metallic object is not a perfect reflector. My comments are based solely on the observations of all the small experiments I have conducted. I welcome any feedback/critisism that can help explain these issues.

What I need to explain is why over a period of 3 hrs with the computers on (and transmiting), the amount of 'noise' on my spectrum analyzer was slowing increasing. When the computers were then shut off the amount of noise drops to almost nothing, as it should, but it is still not as low as when the computers have been off for a short period 5-10 mins. If I turn the computer back on it starts all over. I ended up just wiring all the computer terminals with cat5 because the wireless connections to the individual computers would become unstable after about 3 hrs (constant drops and reconnects). The computers still reported excellent signal strengths, with noise values of -89 (up from -97 when the computers were just booted up). That amount of noise should not be enough to prevent connections, so yes there must be another explanation, but I haven't found it yet. As I wired the connections directly, and haven't come across another customer with the same unique scenario I am not looking into the matter that much anymore.

Every object on earth does have some degree of microwave absorbtion and even a metallic object is not a perfect reflector. My comments are based solely on the observations of all the small experiments I have conducted. I welcome any feedback/critisism that can help explain these issues.

I had the good fortune of working two summers while in college at Oak Ridge National Lab --- I was so green (compared to 6,000 PhDs at ORNL) that the first summer I was assigned a project to measure the attenuation coefficient of almost anything from which a standard target could be made there at the lab, so I agree, only a vacuum doesn't absorb.

The computers still reported excellent signal strengths, with noise values of -89 (up from -97 when the computers were just booted up). That amount of noise should not be enough to prevent connections, so yes there must be another explanation, but I haven't found it yet. As I wired the connections directly, and haven't come across another customer with the same unique scenario I am not looking into the matter that much anymore.

Thirty (30) years ago, a Tektronics 465 scope would show you a different graph than a Tektronics 475 of just about any signal (save a battery), so the bandwidth of the measuring instrument may not be adequate to show you what is interfering with the primary signal.

Measuring at frequencies below the minimum required to spot the problem results in "aliasing" (read: missing certain events) (in the time domain). I dunno what it is called in the F (frequency) domain. So, seismic crews typically record at 4X the frequency of the fastest event they want to see.

Consider the case of two tuning forks, one tuned to middle C, one tuned to D. If both are struck at the same time, what frequencies does one hear?

IOW, if you sample at 24 hour intervals, an airplane might be in the same position parked on the tarmac each day, but if you look at 12 hour intervals, you may not find it there half the time!

Google until you find the seven steps of the "scientific method" in order to learn more about how scientists gather data and proceed to publish a scientific law. IIRC Einstein worked on the General Theory of Relativity for 25 years and was unable to advance the theory to the status of a law. Again, IIRC, from his autobiography, he blamed his deficiencies in math!

best regards/ldv

hi there!

i do not like to bore you and I've taken up enough of your time, but there nobody tell me what kind of problem is

sr9 with 50% NLOS 8km link;

-75 to -80dBm signal strenght;

100Kbps bandwith test or even no ping with that constant signal;

i lookong for 1-2MBps link.

we have replaced all but cards 3 times. all - cables, antennas and even routerboards.

is it a card problem or so, is it a configuration problem? 2437 2ghz-5mhz. or i need -70dBm or low and make an AP in the middle. but why using sr9 (not sr2) with Line Of Site. we are using sr9 if we wanna make NLOS links, aren't we?

and I personnaly cannot beleive that "these cards cannot work and transfer 2 MBps if there is no -70dBm or less signal " what my vendor asserts.

regards,
C. G.

Have you update the firmrware on RB boards?

Last time I have partially solved the issue updating the routerboard firmware.

BR.
Max

For all your clever people!!

1. SR9 is a 900mhz card!

2. SR2 is a 2.4GHz card!

3. SR5 is a 5Ghz card!

Each card have their specific ranges that it can work in! Please select proper antenna for each card!

For Sr9 on 2ghz !

For the RF house As we all know, basic wireless training! Not all sites is suitable for wireless! In your case with the 4 x laptops and shielded house:

1. Rf signals is becoming out of fase due to reflection etc! that will cause RF noise! (Fact)

2. When shutting down laptops, wireless carrier wave does not switch of instantaniously. (windows first try to shut down etc.)

I hope this is clear and will save a few people from embarrising them selfs!

I am open to any comments!

RF technician for 12 years

MR G