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Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 3:11 am
by mushmx
Hi, well i had a trouble with my link point to point of 64km, I using
2 Router 532 with Wlan card higher again
2 heavy duty 28dbi
2 Tower of 60mts high.

When i do the link TX/RX : 72/77 and TX/RX: 24/36mb for 5 or 10 minute work very well, but the next day my link is very intermittent and the TX/RX increment to 92/95.

What is wrong? is very far 64km?

Note: I used TX Power (Default, 20, 24, 26, 28, 30) but nothing fix the problem.

Re: Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 11:14 am
by skillful
check your pigtails and connectors for loose or partial contact.

Re: Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 12:44 pm
by chvdr
hi there!
you can find many posts onto the forum with that treatement. but i think that you have a porblem related to cables, antennas, etc. signal levels <if they perpetual, ofcourse> are quite enought to pass 30Mbps of traffic. we have similar link tx/rx=72/72 with 25Mbps full duplex.

Re: Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 5:56 pm
by galaxynet
mushmx -
Note: I used TX Power (Default, 20, 24, 26, 28, 30) but nothing fix the problem.
Where did you get these 'default' power settings from? I know of no wireless card that does 30db.....

If you manually set the power out of the card(s) to those you listed above you most likely damaged the cards and will have to get new ones.

Since you are using a RB532 and high power cards I am going to guess that you are using XR5 or XR2 cards. In a RB532 you have to set the power at 10 less than you actually want - like this - if you want 26db out then you need to set the power manually at 16. If it were me I'd just let the RB set it to default and leave it at that.

If it worked one day and not the next then;
1) If the cards are not damaged then it could be a cable/connector problem.
2) If you have had bad weather lately it could water intrusion in to the cable, connector, enclosure or a combination of any of the three.
3) Bad weather again - possibly the antennas were moved by high winds?

Re: Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 8:53 pm
by mushmx
Thank you for your pots.

The situation is very rare because we changed all one by one and we tested in every change in both towers and currently are new.

The last weekend the weather was raining and fast wind but this week the weather was sunny and not wind. We did the next changes in this order:

1.-the cable rj45
2.-Coxial cable
3.-Pigtails
4.-Heavy Duty
5.-RB532
6.-The position of the antennas

Good Link
MB tx/rx: 24/36
Signal tx/rx: 72/77 (Sometimes with this signal we try it pass a file "400mb" from tower1 to tower2 and the link is broked, but if we do the same from tower2 to tower1 the transfer is passed) :(

Bad Link
MB tx/rx: 6/12
Signal tx/rx: 92/95 (Link Broked)

================================
One router are damaged, I suppose because the TX Power was higher (TX Power Manual = 30)

My wlan card are Mikrotik SR50 (300Mw)
================================

With all these change the link continue intermitent.

Re: Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 10:08 pm
by chvdr
My wlan card are Mikrotik SR50 (300Mw)

what actually card you used

Re: Trouble with link point to point 64km

Posted: Sun Nov 18, 2007 11:28 pm
by ghmorris
Hi, well i had a trouble with my link point to point of 64km, I using
2 Router 532 with Wlan card higher again
2 heavy duty 28dbi
2 Tower of 60mts high.

When i do the link TX/RX : 72/77 and TX/RX: 24/36mb for 5 or 10 minute work very well, but the next day my link is very intermittent and the TX/RX increment to 92/95.

What is wrong? is very far 64km?

Note: I used TX Power (Default, 20, 24, 26, 28, 30) but nothing fix the problem.
I see you are in Cancun. How much of this link is over water?

Tidal variation can make a big difference in link quality.

You also have very little fade margin for a link of this length. Normal variation in signal strength would be enough to take the link down.

In a tropical environment rain fade at 5.8GHz is also a factor on very long links.

Are you running RB52H cards?

George

Re: Trouble with link point to point 64km

Posted: Mon Nov 19, 2007 12:56 am
by doush
1- be sure about the cards you use.. SR series are 400mW cards..
2- Do not change the default tx power settings, leave them default
3- Enable Nstreme on both sites
(4- Check for rarely used channels like ch 14 for less intereference )

Re: Trouble with link point to point 64km

Posted: Mon Nov 19, 2007 2:33 am
by WirelessRudy
So, under certain conditions your link becomes marginal, resulting in dropouts

I would first look to the path of the radio signals. Are the towers high enough for such distance? Only LOS (Line of Sight) is not enough, think about the fresnell (´belly´ of the signal path) that has to stay clear of any or most objects (trees!).
In this relation, a path over water with its tidal differences can make a difference.
Then, radio signals are always influenced by atmospheric conditions like moisture, rains, snow, temperature etc and even day or night, or more specially dusk and dawn. With strong connections -70 and better, this would normally not be such an issue but I think your best link connectivity is pushed in the marginal condition under some conditions.
And yes, don't push your cards to much. Max. power outputs of the cards will overheat it resulting in unstable performances (that might also be the reason of your drop outs) and finally death. Leave setting to or close around the default 17dbm.

Re: Trouble with link point to point 64km

Posted: Mon Nov 19, 2007 2:47 am
by mushmx
Hello George

The link not crooss over the sea or lagoon is just jungle. And sorry for the bad information of the wlan card, actually i'm using the wlan card RB52H (350mW) and is very rare because I have a link point to point with the same feacture over the sea (Playa del carmen to Cozumel Island) and working without trouble the only diferent is the distance "40km".

===========================================================

Hello Doush

Yeah i was worng, the wlan card are RB52H.
The tx power actually is 26 because with default haven't link, only with 26 i can do the link, also i changed the frencuency.

never happend me this situation. The next test are uses an other antennas with more dbi if this not working mmmm maybe be install and other point between the 2 tower.

Cancun <--------------->Playa del Carmen (64km) "Current Link"

Cancun <---->(30km) Pto. Morelos <-----> Playa del Carmen(34km) "Alternative"

Re: Trouble with link point to point 64km

Posted: Mon Nov 19, 2007 9:42 am
by promind
Hello George

The link not crooss over the sea or lagoon is just jungle. And sorry for the bad information of the wlan card, actually i'm using the wlan card RB52H (350mW) and is very rare because I have a link point to point with the same feacture over the sea (Playa del carmen to Cozumel Island) and working without trouble the only diferent is the distance "40km".

===========================================================

Hello Doush

Yeah i was worng, the wlan card are RB52H.
The tx power actually is 26 because with default haven't link, only with 26 i can do the link, also i changed the frencuency.

never happend me this situation. The next test are uses an other antennas with more dbi if this not working mmmm maybe be install and other point between the 2 tower.

Cancun <--------------->Playa del Carmen (64km) "Current Link"

Cancun <---->(30km) Pto. Morelos <-----> Playa del Carmen(34km) "Alternative"
try xr5 and write back.
I have exactly the same problem.
2 days with very good signal -50/-48 26km link with r52h then -88/-48
replaced 1st r52h with zcom 622XA and singel reduced to -75 a few days later replaced the other r52h with xr5 and signal is now -49/-41 -> 2 weeks no change

Re: Trouble with link point to point 64km

Posted: Tue Nov 27, 2007 2:42 pm
by doush
did you guys tried enabling Nstreme (not dual) ?
It helps a lot especially in long distances...

Re: Trouble with link point to point 64km

Posted: Sun Dec 30, 2007 7:37 pm
by onowojemma
Hello My Gurus
pleas am searching the Mikrotik manual on how to enable Nstreme not dual but have not seen any thing on it can some one help me out.
thanks in advance

Re: Trouble with link point to point 64km

Posted: Sun Dec 30, 2007 11:30 pm
by jwcn
It's in the manual under wireless interfaces.

Re: Trouble with link point to point 64km

Posted: Mon Dec 31, 2007 8:50 am
by shielder
maybe because of the rain fade that makes your link unstable.

and i don't think 60 meter tower would be high enough for 60 km link. it would be some how unstable.

Re: Trouble with link point to point 64km

Posted: Wed Jan 02, 2008 4:57 am
by tgrand
What are you usng for power supplies?

Re: Trouble with link point to point 64km

Posted: Sat Jan 05, 2008 7:02 pm
by Tanker
Again - just my 02 cents worth...
=========================

It is either a bad LMR.. or...
Bad Power Supplies...

We've had a couple of these instances and every time it's turned out to be as above
- LMR wet or badly made
- rubbish Power suppy with fluctuating voltages.

Of course - as you change up to XR5's.. the more power (wattage) required. We've found that by using "clean" power - 12V - from a battery solves this issue. We have long distance links (~70Km) and we cannot afford to be running after this type of thing.. and have done extensive testing to stop these issues.

Operating off 48V doesn't help either - imho - because of the losses over the on-board transformer.. but.. like I say - my opinion only and that's why we decided to run the boards on 12V.

It's an irritating challaenge - but once you've nailed it it'll all come together.

Regards

Re: Trouble with link point to point 64km

Posted: Sat Jan 12, 2008 10:52 am
by BobcatGuy
[/quote]
try xr5 and write back.
I have exactly the same problem.
2 days with very good signal -50/-48 26km link with r52h then -88/-48
replaced 1st r52h with zcom 622XA and singel reduced to -75 a few days later replaced the other r52h with xr5 and signal is now -49/-41 -> 2 weeks no change[/quote]


Just wanted to pont out that there was another RB52H that had good signal, then suddenly dropped signal significantly! Mine did that as well, actually 2 days as well. Was there a problem with RB52H that we did not know about? And I thought I messes sompthing up!
Makes for a good short range testing card, thats about it!

Re: Trouble with link point to point 64km

Posted: Sat Feb 09, 2008 7:55 am
by mushmx
Finally I did the link point to point, well I used 2 card XtremeRange of 600Mw into my routerboard 532 mikrotik, but something rare happened when I increased the TX POWER of AP BRIDGE, the router began reboot until that I connected via telnet mac to reset it.

In the side of STATION WDS I can increase the TX Power to 20 no more because then the AP Bridge began reboot. so finally we decided the next configuration:
STATION WDS:
TX POWER: 20
"MANUAL TXPOWER"
Processor router: 333MHZ
AP BRIDGE:
TX POWER: DEFAULT
"REGULATORY DOMAIN"
Processor router:333MHZ
We got it the next result STABLE:

TX/RX RATE: 18Mbps.
TX/RX TRANSMISION: 80/87
-----------------------------------------------
I think the problem maybe are the antennas "Heavy duty of 28dbi" and we need others kind of antenna with more DBI to get a excellent link.

EQUIPMENT:
2 ROUTERBOARD 532
2 XTREMERANGE 600Wm
2 Antenna heavy duty of 28dbi
1 tower "AP BRIDGE" 80mts.
1 tower "Station WDS" 60mts.
Distance 64kms.


How I can increase over the TX POWER?

Re: Trouble with link point to point 64km

Posted: Sat Feb 09, 2008 12:50 pm
by RK
How I can increase over the TX POWER?[/color]
You are supposed to use default power. You can burn your device and get poor performance if you mess with the power settings.

Re: Trouble with link point to point 64km

Posted: Sat Feb 09, 2008 5:15 pm
by mushmx
How I can increase over the TX POWER?[/color]
You are supposed to use default power. You can burn your device and get poor performance if you mess with the power settings.
Thanks for the reply.

So if I can't increase the TX POWER, I need use other antenna with more DBI?

The distance is 64km and I've 2 tower (cancun tower 80mts High - Playa tower 60mts high)

Re: Trouble with link point to point 64km

Posted: Tue Feb 12, 2008 7:42 am
by chvdr
ofcourse, much bigger antenna is an obligation. 64km is serious long distance and good antenna dimension is ab. 2m. and above.

appropos, how bigger is yours? 28dBi is quite little dish... very small.

Re: Trouble with link point to point 64km

Posted: Wed Feb 13, 2008 12:13 pm
by Tanker
A 2 meter antenna 80 meters up is going to be FUN!!!! - NOT...

If you could just lift your Side B to ± 80 meters as well you'd be able to establish a good link using normal grids

I've done a Fade margin Calc and Fresnel profile and it could work
Let me know if you need some more help.

T

Re: Trouble with link point to point 64km

Posted: Thu Feb 14, 2008 12:03 am
by chvdr
A 2 meter antenna 80 meters up is going to be FUN!!!! - NOT...
it's not "FUN!!!!"... it is possible. believe me. futhermore, originally mushmx said
2 Tower of 60mts high.
... "If you could just lift your Side B to ± 80 meters as " us much more funnest.

Re: Trouble with link point to point 64km

Posted: Wed Apr 23, 2008 4:59 pm
by mushmx
Hi everybody

Thank's for all reply, I continue with this link :shock: and I read all the post but i have a doubt about what model, kind and mark of antenna i need buy? no matter if is european or american product.


Thanks, best regard. :lol:

Re: Trouble with link point to point 64km

Posted: Thu Apr 24, 2008 8:02 am
by Belyivulk
Sounds to me like the 350mW cards are broken. We have had this happen MANY times with R52H

Re: Trouble with link point to point 64km

Posted: Fri Apr 25, 2008 8:27 am
by chvdr
yes, every time we replace antenna cables and wless cards. i suppose, it is COMPULSORY when you search what is goin' on in same case or related.

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 12:42 am
by awamex
Hi chvdr and Belyivulk

It's me mushmx 8) thank's for the reply but what kind and mark of antenna recommend me to use with this link? and if you know some website please post it.


Thanks, best regard.

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 12:44 am
by Belyivulk
we have a 58km link here in NZ, with Mikrotik 30DB Dish antennas, R52H, Mikrotik Pigtail & LMR400. We get -69 / -71 for signal

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 4:37 am
by awamex
we have a 58km link here in NZ, with Mikrotik 30DB Dish antennas, R52H, Mikrotik Pigtail & LMR400. We get -69 / -71 for signal
Thanks for the reply Belyivulk

I'm using the next equipments:

2 Routerboard 532
2 Wireless card XTREMERANGE 600Wm
2 Antenna heavy duty of 28dbi
1 tower "AP BRIDGE" 80mts.
1 tower "Station WDS" 60mts.
Distance 64kms.

The situation is very rare because I got a excellent link between TX/RX 60-70 with 18/24Mb transfers but inexplicably the link become degrade until to dead signal and the only reason that come to my mind is that some signal of the airport is interfering with my link :? so I checked all cables, pigtail, router, antenna, etc.... and nothing repair the trouble, so I think maybe if I change the antenna to other with more DBI like 36dbi maybe repair the link.

What do you thing about this?

Note. mostly the link cross the jungle and the only build is the airport and we are a sea level.

Heri

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 4:50 am
by Belyivulk
What frequency are you using? 57xx?

Have you tried the frequency usage tool? What is your noise floor when the link is good? what does it become when it gets bad? What is the humidity like? What time of day does the link go bad, and for how long. How do you fix it? What type of cable are you using from the pigtails to the antennas? are you weather sealing it correctly?

These are all questions i need answers too, lol

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 5:31 am
by awamex
What frequency are you using? 57xx?

Have you tried the frequency usage tool? What is your noise floor when the link is good? what does it become when it gets bad? What is the humidity like? What time of day does the link go bad, and for how long. How do you fix it? What type of cable are you using from the pigtails to the antennas? are you weather sealing it correctly?

These are all questions i need answers too, lol
I'm using the band 5.8ghz and frequency 5822

Heri

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 5:32 am
by Belyivulk
Try using a lower frequency, 5745, or even to test, set your country to germany and use 5500 (to test only)

If your link stays up you can be sure the problem is interference, if not, you know the problem lies elsewhere

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 6:25 am
by awamex
Try using a lower frequency, 5745, or even to test, set your country to germany and use 5500 (to test only)

If your link stays up you can be sure the problem is interference, if not, you know the problem lies elsewhere
Ok, I'll do the test the next week.

Thanks Belyivulk :D

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 7:14 am
by Belyivulk
No worries :)

The other thing is time. Does the link go down first thing in the morning after sunrise?

Re: Trouble with link point to point 64km

Posted: Sat Apr 26, 2008 6:57 pm
by awamex
No worries :)

The other thing is time. Does the link go down first thing in the morning after sunrise?
The link go down without matter the time is variable :(