PTP400 noise following signal :-s

Hi all,

I have installed a PTP400 (5.4Ghz) in replacement of BH20 (5.7Ghz). One end at the core node, and the remote side in a FM tower. At the tower there are 5 AP(5.7) and CMM, and at Node we have 1BH20 (5.7), 2 BH20 (5.2), and 1 BH10 (5.7). So the topology is something like this:

5AP|CMM|PTP400---------(900meters)----------PTP400|2xBH20|2xBH10

All with FTP cable avoiding ethernet cable interference. The PTP400 was working excellente for 10 days, after that the link falling apart with high noise levels at the remote side (high pings, link down…). However in Node site there is no noise at all. We are alone with Canopy int the city and there was no other equipment addition at the remote site.

When I try moving channel, let say noise is on channel 10, I move to channel 5. So… noise still in 10 and takes channel 5 too. So… I move again to channel 2…and noise still in channel 10 and 5, now takes also chanel 2 and may be chanel 1 too. And so on… Afternoise takes all channel I have to reboot the unit and all is clear for about 2 minutes… and then again, noise move to the channel working.

I tryed iDFS, independent frequency selection in each site, rising power, fixing frequency, barring all channel except one… nothing works.

Also I tryed using just channels above 5600 to avoide interferece with 5.2Ghz band BH (like some Moto Release Note says), but it doesn’t work.

Any body with experience in PTP 400 could help me please?

Thanks very much in advance

zeta wrote:
Hi all,

I have installed a PTP400 (5.4Ghz) in replacement of BH20 (5.7Ghz). One end at the core node, and the remote side in a FM tower. At the tower there are 5 AP(5.7) and CMM, and at Node we have 1BH20 (5.7), 2 BH20 (5.2), and 1 BH10 (5.7). So the topology is something like this:

5AP|CMM|PTP400---------(900meters)----------PTP400|2xBH20|2xBH10

All with FTP cable avoiding ethernet cable interference. The PTP400 was working excellente for 10 days, after that the link falling apart with high noise levels at the remote side (high pings, link down..). However in Node site there is no noise at all. We are alone with Canopy int the city and there was no other equipment addition at the remote site.

When I try moving channel, let say noise is on channel 10, I move to channel 5. So.. noise still in 10 and takes channel 5 too. So... I move again to channel 2..and noise still in channel 10 and 5, now takes also chanel 2 and may be chanel 1 too. And so on... Afternoise takes all channel I have to reboot the unit and all is clear for about 2 minutes... and then again, noise move to the channel working.

I tryed iDFS, independent frequency selection in each site, rising power, fixing frequency, barring all channel except one... nothing works.

Also I tryed using just channels above 5600 to avoide interferece with 5.2Ghz band BH (like some Moto Release Note says), but it doesn't work.

Any body with experience in PTP 400 could help me please?

Thanks very much in advance


Take a look at the spectrum analyzer on BOTH ends of the link. You can utilize this to see where your noise is at and lock out channels you do not want to link to operate in. The best part is you can have both ends of the link operating on different channels.

Jhon,

the proble is whatever channel I choose, the noise take that channel too.

so youre saying, you move to a clear channel, and it then shows noise, so you move to the next clear channel and there is noise, and so on. When you leave the channel, it still shows noise youre saying. Until you reboot it, every channel you have been on shows noise?

Your radio is probably toast.

If its connectorized, replace the lead, then the antenna.

Talk to somebody in the forums who is knowlegable of groundin, explain your location, take their advice to ensure youre grounded PROPERLY.

If the grounding and external changes dont fix it, your radio is toast.

My money is on a surge of some sort damaging the internals.

Yes,

Just as you say… the noise “eat” every channel I move.
I’m using FTP cable, inside a metalic tube. All grounded, with PTP grounded too…

I’m using conectorized PTP400. In the same tower I have 5 AP (at 70m). This PTP400 is at 30m. I think if PTP is toasted, all other AP Canopys should be toasted too. What do you think?

Best regards.

Im new to the PTP series, we only have 3 links up with it so im no expert. But from what Ive seen, the spectrum analyzer is pretty good.

I would think if the channel is clear and you switch to it and then noise shows up that its some sort of self interference, due to something like a faulty antenna or a local reflection, etc. But when you switch to another channel, the noise should leave the channel you were on. If it doesnt then one of two things is happenning, the radio isnt seeing the noise that is there for whatever reason until you get onto the channel which could still be a faulty antenna, or there is no noise and the radio is just hosed.

Maybe you could try reflashing the software.

I would definetly get moto tech support on the horn for this, especially if youre still under warranty.

I’ll do and let you know…
This link has only 15 days working (10 working great, 5 working too bad)

Regards

I’m having the same issue with a set of PTP600’s. Running software 54600-07-00. I’m waiting to here back from Motorola on this… Anybody know what is the cause of this??

Are you sure it’s noise? The spectrum graph should show it clearly on the Orthogon if it’s RF interference.

A big problem I have near FM towers is ethernet interference. You can mitigate this by using ferrite beads on each end of the cable.

Ferrite beads are ceramic material that is some type of metal oxide. fair-rite.com has some MgZn based beads that absorb 20-300MHz. They call it “material 46.” It covers 10Mb, 100Mb, and 1000Mb ethernet which I believe are 25MHz, 100MHz, and 250MHz over the cable.

The beads actually turn EMI into heat. So if the EMI is really strong, you have to use more beads to dissipate more heat. I would start with one on each end of the cable.

If moving it to 10Mbps resolves the performance issues (assuming 10Mbps is enough for now) then ferrite beads are worth the purchase.

Sounds good. However, I dont think I can get this stuff in Argentina :-s .

Right now, the link was working very well for 8 weeks. Very very strange…

Zeta