Re: [WISPA] FM radio station site strangeness

2009-01-08 Thread Chuck McCown - 3
There are pseudo square waves on ethernet.  Those have an infinite number of 
harmonics. 
  - Original Message - 
  From: Brian Rohrbacher 
  To: WISPA General List 
  Sent: Wednesday, January 07, 2009 10:11 PM
  Subject: Re: [WISPA] FM radio station site strangeness


  I installed a cat5 cable next to a guys police scanner one time and as soon 
as I plugged the cable (lan cable from poe to computer) in the police scanner 
stayed keyed up on 15o or 155 mhz as I remember.  Unplugged the cable and the 
scanner started scanning again, so I always thought it was 150 some mhz.

  Brian

  Marlon K. Schafer wrote: 
So far all I can find on the internet is that ethernet is at either 12.5 or 
31.25mhz.  NOT 350, that's gigE, not 10/100.

Also, this tower is a 100' wooden pole.  Can't move anywhere really.
marlon

- Original Message - 
From: Adam Goodman a...@wispring.com
To: WISPA General List wireless@wispa.org
Sent: Wednesday, January 07, 2009 9:15 AM
Subject: Re: [WISPA] FM radio station site strangeness


  It also sounds like there is a new leak in the waveguide. One more
thing you might try is to move the cable from leg to leg on the tower
so that you variable length sections that do not resonate at 350MHz or
~100MHz (FM transminssion).


On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:
We also colocate with an FM transmitter. Only 1300W though. we also
had interference on our Ethernet lines. We solved it by moving radios
away from the FM antenna (3 feet or so on a 90' tower) We also
installed ferrits which helped (I actually used a conduit pipe).
Grounding the cat5 helped too.

I would think that if you find that you need more shielding. put all
your cat5 cables in a conduit and install abreakout box at the top of
the tower. If your area is prone to electrical storms (where isn't
these days?!) you will at some point be very sorry you didn't grount
(and well!!)



On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
wrote:
  Hi All,

I think we finally have this all figured out.  Now I just have to figure 
out
how to fix it.

We've been up there for over 6 years now.  It's certainly been a 
problematic
site though.  Constant channel changes (we have 3 competitors a mile 
away
and pick up hundreds of ap's from in town) are the norm.

This fall (a month or two ago) one of the tenants left the building. 
This
cleared out most of the hardware that was in there.  A little bit before
that I replaced an Inscape Data and a smartBridges combo with a single 
MT
access point, using one of the cables that had been working for one of 
the
other two.

About a week ago things started to really act up.  Multiple devices were
having trouble.  I was able to catch it in the act finally.  This time 
the
problem wasn't a wireless issue, the devices were constantly 
disconnecting
and reconnecting at the switch level.

I pulled the Cisco switch out and dropped in a Netgear unit.  That 
didn't
fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
wouldn't connect right either.

I finally had to pull all of the hardware off of the shelf and set most 
of
it on the floor (or just let it hang there) to get it working at all 
well.
Still not perfect but better.

I had by now hiked up there through sometimes knee deep snow 3 or 4 
times.
Next I took a motorbike with studded snow tires up and got permission to
turn down the power to the radio station.  That didn't fix the problem
either.

Next I borrowed a snowmobile and hauled some help and my spectrum 
analyzer
up.  I was unable to see any signals that didn't belong.

Next day, another hike up the hill.

OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
switch.  DC current or something.  So I started testing the cables that 
run
to the most problematic units.  Well now, look at that.  Bad cable.  In 
fact
there are three of them.  Hmmm, kinda strange though.  All three have 
the
exact same fault!  Oh well, better change them out anyway.  I ran three 
new
cable runs and just for kicks I tested one of them.  What the heck? 
The
new cable has the EXACT same fault as the old one!  Even though it 
didn't
follow the exact same path as the old cables.

Man, this is sure looking like a problem caused by the radio station.  I 
was
using indoor cat5 and didn't run lightning protection or ground 
anything.
Yeah I know, but remember that this has been there for a very long time 
like
this.  And as a guy with an electrical background I know that there are
actually two ways to deal with stray electrical.  Grounding is one.
Insulating is another  Anyway, I know it wasn't built to specs.

I added some grounding and that didn't help at all.

Yesterday I finally had one of the local wireless companies (Day 
Wireless)
that mainly does VHF radios, backhaul etc.  They also checked things 
with
the spectrum analyzer but couldn't find anything amiss.  I was able to
duplicate the wiring fault

Re: [WISPA] FM radio station site strangeness

2009-01-08 Thread os10rules
I'm sure if you looked at it on a spectrum analyzer you'd see the  
signal occupies a wide band of frequencies, hence it's probably  
susceptible to interference on a wide range of frequencies.

Greg


On Jan 8, 2009, at 12:54 AM, Marlon K. Schafer wrote:

 OK, can we put this in plain English?  What freq. does 100meg  
 ethernet in
 full or half duplex
 marlon

 - Original Message -
 From: Josh Luthman j...@imaginenetworksllc.com
 To: WISPA General List wireless@wispa.org
 Sent: Wednesday, January 07, 2009 9:07 PM
 Subject: Re: [WISPA] FM radio station site strangeness


 With 100BASE-TX hardware, the raw bits (4 bits wide clocked at *25  
 MHz* at
 the MII) go through 4B5B http://en.wikipedia.org/wiki/4B5B binary
 encoding
 to generate a series of 0 and 1 symbols clocked at *125 MHz* symbol
 ratehttp://en.wikipedia.org/wiki/Symbol_rate.
 The 4B5B encoding provides DC equalization and spectrum shaping  
 (see the
 standard for details)[*citation
 neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_needed
 *]. Just as in the 100BASE-FX case, the bits are then transferred  
 to the
 physical medium attachment layer using
 NRZIhttp://en.wikipedia.org/wiki/NRZIencoding. However, 100BASE-TX
 introduces an additional, medium dependent
 sublayer, which employs MLT-3 http://en.wikipedia.org/wiki/MLT-3  
 as a
 final encoding of the data stream before transmission, resulting in a
 maximum fundamental frequency of* 31.25 MHz*. The procedure is  
 borrowed
 from the ANSI X3.263 FDDI
 http://en.wikipedia.org/wiki/FDDIspecifications, with minor
 discrepancies.
 [3] http://en.wikipedia.org/wiki/Fast_Ethernet#cite_note-mlt3-2

 Source: http://en.wikipedia.org/wiki/Fast_Ethernet
 Josh Luthman
 Office: 937-552-2340
 Direct: 937-552-2343
 1100 Wayne St
 Suite 1337
 Troy, OH 45373

 Those who don't understand UNIX are condemned to reinvent it, poorly.
 --- Henry Spencer


 On Thu, Jan 8, 2009 at 12:02 AM, Marlon K. Schafer
 o...@odessaoffice.comwrote:

 So far all I can find on the internet is that ethernet is at  
 either 12.5
 or
 31.25mhz.  NOT 350, that's gigE, not 10/100.

 Also, this tower is a 100' wooden pole.  Can't move anywhere really.
 marlon

 - Original Message -
 From: Adam Goodman a...@wispring.com
 To: WISPA General List wireless@wispa.org
 Sent: Wednesday, January 07, 2009 9:15 AM
 Subject: Re: [WISPA] FM radio station site strangeness


 It also sounds like there is a new leak in the waveguide. One more
 thing you might try is to move the cable from leg to leg on the  
 tower
 so that you variable length sections that do not resonate at  
 350MHz or
 ~100MHz (FM transminssion).


 On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com
 wrote:
 We also colocate with an FM transmitter. Only 1300W though. we  
 also
 had interference on our Ethernet lines. We solved it by moving  
 radios
 away from the FM antenna (3 feet or so on a 90' tower) We also
 installed ferrits which helped (I actually used a conduit pipe).
 Grounding the cat5 helped too.

 I would think that if you find that you need more shielding. put  
 all
 your cat5 cables in a conduit and install abreakout box at the  
 top of
 the tower. If your area is prone to electrical storms (where isn't
 these days?!) you will at some point be very sorry you didn't  
 grount
 (and well!!)



 On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer 
 o...@odessaoffice.com
 wrote:
 Hi All,

 I think we finally have this all figured out.  Now I just have to
 figure
 out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a
 problematic
 site though.  Constant channel changes (we have 3 competitors a  
 mile
 away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the  
 building.
 This
 cleared out most of the hardware that was in there.  A little bit
 before
 that I replaced an Inscape Data and a smartBridges combo with a
 single
 MT
 access point, using one of the cables that had been working for  
 one
 of
 the
 other two.

 About a week ago things started to really act up.  Multiple  
 devices
 were
 having trouble.  I was able to catch it in the act finally.  This
 time
 the
 problem wasn't a wireless issue, the devices were constantly
 disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.   
 That
 didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot  
 device.
 That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and  
 set
 most
 of
 it on the floor (or just let it hang there) to get it working  
 at all
 well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3  
 or 4
 times.
 Next I took a motorbike with studded snow tires up and got  
 permission
 to
 turn down the power to the radio station.  That didn't fix the
 problem
 either.

 Next I borrowed a snowmobile

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Adam Goodman
We also colocate with an FM transmitter. Only 1300W though. we also
had interference on our Ethernet lines. We solved it by moving radios
away from the FM antenna (3 feet or so on a 90' tower) We also
installed ferrits which helped (I actually used a conduit pipe).
Grounding the cat5 helped too.

I would think that if you find that you need more shielding. put all
your cat5 cables in a conduit and install abreakout box at the top of
the tower. If your area is prone to electrical storms (where isn't
these days?!) you will at some point be very sorry you didn't grount
(and well!!)



On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
wrote:
 Hi All,

 I think we finally have this all figured out.  Now I just have to figure out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a problematic
 site though.  Constant channel changes (we have 3 competitors a mile away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building.  This
 cleared out most of the hardware that was in there.  A little bit before
 that I replaced an Inscape Data and a smartBridges combo with a single MT
 access point, using one of the cables that had been working for one of the
 other two.

 About a week ago things started to really act up.  Multiple devices were
 having trouble.  I was able to catch it in the act finally.  This time the
 problem wasn't a wireless issue, the devices were constantly disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most of
 it on the floor (or just let it hang there) to get it working at all well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 times.
 Next I took a motorbike with studded snow tires up and got permission to
 turn down the power to the radio station.  That didn't fix the problem
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum analyzer
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
 switch.  DC current or something.  So I started testing the cables that run
 to the most problematic units.  Well now, look at that.  Bad cable.  In fact
 there are three of them.  Hmmm, kinda strange though.  All three have the
 exact same fault!  Oh well, better change them out anyway.  I ran three new
 cable runs and just for kicks I tested one of them.  What the heck?  The
 new cable has the EXACT same fault as the old one!  Even though it didn't
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I was
 using indoor cat5 and didn't run lightning protection or ground anything.
 Yeah I know, but remember that this has been there for a very long time like
 this.  And as a guy with an electrical background I know that there are
 actually two ways to deal with stray electrical.  Grounding is one.
 Insulating is another  Anyway, I know it wasn't built to specs.

 I added some grounding and that didn't help at all.

 Yesterday I finally had one of the local wireless companies (Day Wireless)
 that mainly does VHF radios, backhaul etc.  They also checked things with
 the spectrum analyzer but couldn't find anything amiss.  I was able to
 duplicate the wiring fault for them (with my Ideal tester).  But suddenly
 everything cleared right up!  Stuff was looking good, no cable fault etc.
 Pings were looking good, devices were finally negotiating the connections
 right etc.

 I called the radio station to ask if I could try turning the power down
 again to see if we see any change on the spectrum analyzer.  They said they
 thought that I'd already done that because the showed the power was way
 down.  Turns out someone in the building had bumped a breaker and shut down
 part of the transmitter!  Well, we got all of that figured out and guess
 what.  All of the problems came right back!  I then turned the power back
 down and they cleared up.

 Tip for you guys, dropping an 18,000 watt system down by even 60% of it's
 normal output isn't always enough.  We had to drop down to 10 to 20% to get
 the problems to clear up.  The guys from Day Wireless had some small ferrite
 beads with them so we stuck them onto the cables.  Put the beads on and the
 radios would negotiate at 100full.  Take them off and they'd drop right back
 to 100 half.  Duplicatable all day long.

 S, current theory is that the radio station is screwing up my cat5
 connections.  The fact that the building has less hardware in it and we have
 more snow up there than normal has probably caused some different 

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Dennis Burgess - Linktechs.net
We had a site with a 1000 watt AM Hotstick about 100 feet from another 
tower.  We ran the cable (non-shielded outdoor rated) and crimped the 
end at the top of the tower.  The installer all of a sudden, felt a 
burning sensation on his thumb with that wonderful smell of burning 
skin.  Guess what, he was holding the end of the cat5, not plugged into 
anything, just ran up the tower!  Sure enough, nice little burn marks 
right where the copper pins on the cat5 was! 

Put in a few ferrite beads, never looked back.  fun stuff to say the 
least.  ON a side note, we are at 400 foot on a 1400 foot FM tower 
transmitting at 100,000 watts at the top.  We ran Power up, but have a 
440 foot non-poe cat5 down, and don't have any issues! lol

--
* Dennis Burgess, CCNA, A+, Mikrotik Certified Trainer
WISPA Board Member - wispa.org http://www.wispa.org/
Link Technologies, Inc -- Mikrotik  WISP Support Services*
*Office*: 314-735-0270 *Website*: http://www.linktechs.net 
http://www.linktechs.net/

*/ Link Technologies, Inc is offering LIVE Mikrotik On-Line Training 
http://www.linktechs.net/onlinetraining.asp/*



Marlon K. Schafer wrote:
 Hi All,

 I think we finally have this all figured out.  Now I just have to figure out 
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a problematic 
 site though.  Constant channel changes (we have 3 competitors a mile away 
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building.  This 
 cleared out most of the hardware that was in there.  A little bit before 
 that I replaced an Inscape Data and a smartBridges combo with a single MT 
 access point, using one of the cables that had been working for one of the 
 other two.

 About a week ago things started to really act up.  Multiple devices were 
 having trouble.  I was able to catch it in the act finally.  This time the 
 problem wasn't a wireless issue, the devices were constantly disconnecting 
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That didn't 
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That 
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most of 
 it on the floor (or just let it hang there) to get it working at all well. 
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 times. 
 Next I took a motorbike with studded snow tires up and got permission to 
 turn down the power to the radio station.  That didn't fix the problem 
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum analyzer 
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the 
 switch.  DC current or something.  So I started testing the cables that run 
 to the most problematic units.  Well now, look at that.  Bad cable.  In fact 
 there are three of them.  Hmmm, kinda strange though.  All three have the 
 exact same fault!  Oh well, better change them out anyway.  I ran three new 
 cable runs and just for kicks I tested one of them.  What the heck?  The 
 new cable has the EXACT same fault as the old one!  Even though it didn't 
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I was 
 using indoor cat5 and didn't run lightning protection or ground anything. 
 Yeah I know, but remember that this has been there for a very long time like 
 this.  And as a guy with an electrical background I know that there are 
 actually two ways to deal with stray electrical.  Grounding is one. 
 Insulating is another  Anyway, I know it wasn't built to specs.

 I added some grounding and that didn't help at all.

 Yesterday I finally had one of the local wireless companies (Day Wireless) 
 that mainly does VHF radios, backhaul etc.  They also checked things with 
 the spectrum analyzer but couldn't find anything amiss.  I was able to 
 duplicate the wiring fault for them (with my Ideal tester).  But suddenly 
 everything cleared right up!  Stuff was looking good, no cable fault etc. 
 Pings were looking good, devices were finally negotiating the connections 
 right etc.

 I called the radio station to ask if I could try turning the power down 
 again to see if we see any change on the spectrum analyzer.  They said they 
 thought that I'd already done that because the showed the power was way 
 down.  Turns out someone in the building had bumped a breaker and shut down 
 part of the transmitter!  Well, we got all of that figured out and guess 
 what.  All of the problems came right back!  I then turned the power back 
 down and they cleared up.

 Tip for you guys, dropping an 18,000 watt system down by even 60% of it's 
 normal output isn't always 

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Adam Goodman
It also sounds like there is a new leak in the waveguide. One more
thing you might try is to move the cable from leg to leg on the tower
so that you variable length sections that do not resonate at 350MHz or
~100MHz (FM transminssion).


On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:
 We also colocate with an FM transmitter. Only 1300W though. we also
 had interference on our Ethernet lines. We solved it by moving radios
 away from the FM antenna (3 feet or so on a 90' tower) We also
 installed ferrits which helped (I actually used a conduit pipe).
 Grounding the cat5 helped too.

 I would think that if you find that you need more shielding. put all
 your cat5 cables in a conduit and install abreakout box at the top of
 the tower. If your area is prone to electrical storms (where isn't
 these days?!) you will at some point be very sorry you didn't grount
 (and well!!)



 On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
 wrote:
 Hi All,

 I think we finally have this all figured out.  Now I just have to figure out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a problematic
 site though.  Constant channel changes (we have 3 competitors a mile away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building.  This
 cleared out most of the hardware that was in there.  A little bit before
 that I replaced an Inscape Data and a smartBridges combo with a single MT
 access point, using one of the cables that had been working for one of the
 other two.

 About a week ago things started to really act up.  Multiple devices were
 having trouble.  I was able to catch it in the act finally.  This time the
 problem wasn't a wireless issue, the devices were constantly disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most of
 it on the floor (or just let it hang there) to get it working at all well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 times.
 Next I took a motorbike with studded snow tires up and got permission to
 turn down the power to the radio station.  That didn't fix the problem
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum analyzer
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
 switch.  DC current or something.  So I started testing the cables that run
 to the most problematic units.  Well now, look at that.  Bad cable.  In fact
 there are three of them.  Hmmm, kinda strange though.  All three have the
 exact same fault!  Oh well, better change them out anyway.  I ran three new
 cable runs and just for kicks I tested one of them.  What the heck?  The
 new cable has the EXACT same fault as the old one!  Even though it didn't
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I was
 using indoor cat5 and didn't run lightning protection or ground anything.
 Yeah I know, but remember that this has been there for a very long time like
 this.  And as a guy with an electrical background I know that there are
 actually two ways to deal with stray electrical.  Grounding is one.
 Insulating is another  Anyway, I know it wasn't built to specs.

 I added some grounding and that didn't help at all.

 Yesterday I finally had one of the local wireless companies (Day Wireless)
 that mainly does VHF radios, backhaul etc.  They also checked things with
 the spectrum analyzer but couldn't find anything amiss.  I was able to
 duplicate the wiring fault for them (with my Ideal tester).  But suddenly
 everything cleared right up!  Stuff was looking good, no cable fault etc.
 Pings were looking good, devices were finally negotiating the connections
 right etc.

 I called the radio station to ask if I could try turning the power down
 again to see if we see any change on the spectrum analyzer.  They said they
 thought that I'd already done that because the showed the power was way
 down.  Turns out someone in the building had bumped a breaker and shut down
 part of the transmitter!  Well, we got all of that figured out and guess
 what.  All of the problems came right back!  I then turned the power back
 down and they cleared up.

 Tip for you guys, dropping an 18,000 watt system down by even 60% of it's
 normal output isn't always enough.  We had to drop down to 10 to 20% to get
 the problems to clear up.  The guys from Day Wireless had some small ferrite
 beads with them so we stuck them onto the cables.  Put the beads on and the
 radios would 

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Chuck McCown
Think wavelength.
AM wavelengths are hundreds of feet long.
There is a giant reactive near field around the AM antenna.
(Electric fields and Magnetic fields)

Your cat 5 was probing the electric field at two different voltage points.
For AM broadcast frequencies, you can actually take a volt meter and stretch 
the leads out and measure the field on the AC voltage setting.

One end of your cat 5 was tapping the field at a low potential region and 
the other end was at a high potential.  Almost like you have one end of the 
cat 5 connected to ground and now you have climbed onto a high voltage power 
line and are handling the grounded cat 5.  (Just your body being in the 
field is analogous to being on a high voltage power line).

With the much smaller (relatively speaking) wavelength of the FM broadcast 
frequency, the cat 5 crosses multiple high and low voltage nodes in the 
field.  Likely as to be self canceling.
And since your cable is much longer than the FM wavelength there is very 
little chance it is resonant.
Plus the inductance of the cable produces much more inductive reactance to 
the FM signal.

However short cat 5 jumpers can pick up an enormous amount of FM energy and 
very little AM.

- Original Message - 
From: Dennis Burgess - Linktechs.net dmburg...@linktechs.net
To: WISPA General List wireless@wispa.org
Sent: Wednesday, January 07, 2009 10:05 AM
Subject: Re: [WISPA] FM radio station site strangeness


 We had a site with a 1000 watt AM Hotstick about 100 feet from another
 tower.  We ran the cable (non-shielded outdoor rated) and crimped the
 end at the top of the tower.  The installer all of a sudden, felt a
 burning sensation on his thumb with that wonderful smell of burning
 skin.  Guess what, he was holding the end of the cat5, not plugged into
 anything, just ran up the tower!  Sure enough, nice little burn marks
 right where the copper pins on the cat5 was!

 Put in a few ferrite beads, never looked back.  fun stuff to say the
 least.  ON a side note, we are at 400 foot on a 1400 foot FM tower
 transmitting at 100,000 watts at the top.  We ran Power up, but have a
 440 foot non-poe cat5 down, and don't have any issues! lol

 --
 * Dennis Burgess, CCNA, A+, Mikrotik Certified Trainer
 WISPA Board Member - wispa.org http://www.wispa.org/
 Link Technologies, Inc -- Mikrotik  WISP Support Services*
 *Office*: 314-735-0270 *Website*: http://www.linktechs.net
 http://www.linktechs.net/

 */ Link Technologies, Inc is offering LIVE Mikrotik On-Line Training
 http://www.linktechs.net/onlinetraining.asp/*



 Marlon K. Schafer wrote:
 Hi All,

 I think we finally have this all figured out.  Now I just have to figure 
 out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a 
 problematic
 site though.  Constant channel changes (we have 3 competitors a mile away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building. 
 This
 cleared out most of the hardware that was in there.  A little bit before
 that I replaced an Inscape Data and a smartBridges combo with a single MT
 access point, using one of the cables that had been working for one of 
 the
 other two.

 About a week ago things started to really act up.  Multiple devices were
 having trouble.  I was able to catch it in the act finally.  This time 
 the
 problem wasn't a wireless issue, the devices were constantly 
 disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most 
 of
 it on the floor (or just let it hang there) to get it working at all 
 well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 
 times.
 Next I took a motorbike with studded snow tires up and got permission to
 turn down the power to the radio station.  That didn't fix the problem
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum 
 analyzer
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
 switch.  DC current or something.  So I started testing the cables that 
 run
 to the most problematic units.  Well now, look at that.  Bad cable.  In 
 fact
 there are three of them.  Hmmm, kinda strange though.  All three have the
 exact same fault!  Oh well, better change them out anyway.  I ran three 
 new
 cable runs and just for kicks I tested one of them.  What the heck? 
 The
 new cable has the EXACT same fault as the old one!  Even though it didn't
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I 
 was
 using indoor

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread reader
Do you have the shielded cable?

Mark




insert witty tagline here

- Original Message - 
From: Marlon K. Schafer o...@odessaoffice.com
To: WISPA General List wireless@wispa.org
Cc: isp-wirel...@isp-wireless.com
Sent: Wednesday, January 07, 2009 7:47 AM
Subject: [WISPA] FM radio station site strangeness


 Hi All,

 I think we finally have this all figured out.  Now I just have to figure 
 out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a 
 problematic
 site though.  Constant channel changes (we have 3 competitors a mile away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building.  This
 cleared out most of the hardware that was in there.  A little bit before
 that I replaced an Inscape Data and a smartBridges combo with a single MT
 access point, using one of the cables that had been working for one of the
 other two.

 About a week ago things started to really act up.  Multiple devices were
 having trouble.  I was able to catch it in the act finally.  This time the
 problem wasn't a wireless issue, the devices were constantly disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most of
 it on the floor (or just let it hang there) to get it working at all well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 times.
 Next I took a motorbike with studded snow tires up and got permission to
 turn down the power to the radio station.  That didn't fix the problem
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum analyzer
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
 switch.  DC current or something.  So I started testing the cables that 
 run
 to the most problematic units.  Well now, look at that.  Bad cable.  In 
 fact
 there are three of them.  Hmmm, kinda strange though.  All three have the
 exact same fault!  Oh well, better change them out anyway.  I ran three 
 new
 cable runs and just for kicks I tested one of them.  What the heck? 
 The
 new cable has the EXACT same fault as the old one!  Even though it didn't
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I 
 was
 using indoor cat5 and didn't run lightning protection or ground anything.
 Yeah I know, but remember that this has been there for a very long time 
 like
 this.  And as a guy with an electrical background I know that there are
 actually two ways to deal with stray electrical.  Grounding is one.
 Insulating is another  Anyway, I know it wasn't built to specs.

 I added some grounding and that didn't help at all.

 Yesterday I finally had one of the local wireless companies (Day Wireless)
 that mainly does VHF radios, backhaul etc.  They also checked things with
 the spectrum analyzer but couldn't find anything amiss.  I was able to
 duplicate the wiring fault for them (with my Ideal tester).  But suddenly
 everything cleared right up!  Stuff was looking good, no cable fault etc.
 Pings were looking good, devices were finally negotiating the connections
 right etc.

 I called the radio station to ask if I could try turning the power down
 again to see if we see any change on the spectrum analyzer.  They said 
 they
 thought that I'd already done that because the showed the power was way
 down.  Turns out someone in the building had bumped a breaker and shut 
 down
 part of the transmitter!  Well, we got all of that figured out and guess
 what.  All of the problems came right back!  I then turned the power back
 down and they cleared up.

 Tip for you guys, dropping an 18,000 watt system down by even 60% of it's
 normal output isn't always enough.  We had to drop down to 10 to 20% to 
 get
 the problems to clear up.  The guys from Day Wireless had some small 
 ferrite
 beads with them so we stuck them onto the cables.  Put the beads on and 
 the
 radios would negotiate at 100full.  Take them off and they'd drop right 
 back
 to 100 half.  Duplicatable all day long.

 S, current theory is that the radio station is screwing up my cat5
 connections.  The fact that the building has less hardware in it and we 
 have
 more snow up there than normal has probably caused some different eddy
 currents or multipath.  Or some other such strangeness.

 I have some shielded cable and connectors on the way.  I have permission 
 to
 move my gear from one side of the building to the other side.  I've got 
 more
 high end ferrite beads on the way (one that is made for cat 5 and is 

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Marlon K. Schafer
So far all I can find on the internet is that ethernet is at either 12.5 or 
31.25mhz.  NOT 350, that's gigE, not 10/100.

Also, this tower is a 100' wooden pole.  Can't move anywhere really.
marlon

- Original Message - 
From: Adam Goodman a...@wispring.com
To: WISPA General List wireless@wispa.org
Sent: Wednesday, January 07, 2009 9:15 AM
Subject: Re: [WISPA] FM radio station site strangeness


 It also sounds like there is a new leak in the waveguide. One more
 thing you might try is to move the cable from leg to leg on the tower
 so that you variable length sections that do not resonate at 350MHz or
 ~100MHz (FM transminssion).


 On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:
 We also colocate with an FM transmitter. Only 1300W though. we also
 had interference on our Ethernet lines. We solved it by moving radios
 away from the FM antenna (3 feet or so on a 90' tower) We also
 installed ferrits which helped (I actually used a conduit pipe).
 Grounding the cat5 helped too.

 I would think that if you find that you need more shielding. put all
 your cat5 cables in a conduit and install abreakout box at the top of
 the tower. If your area is prone to electrical storms (where isn't
 these days?!) you will at some point be very sorry you didn't grount
 (and well!!)



 On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
 wrote:
 Hi All,

 I think we finally have this all figured out.  Now I just have to figure 
 out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a 
 problematic
 site though.  Constant channel changes (we have 3 competitors a mile 
 away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building. 
 This
 cleared out most of the hardware that was in there.  A little bit before
 that I replaced an Inscape Data and a smartBridges combo with a single 
 MT
 access point, using one of the cables that had been working for one of 
 the
 other two.

 About a week ago things started to really act up.  Multiple devices were
 having trouble.  I was able to catch it in the act finally.  This time 
 the
 problem wasn't a wireless issue, the devices were constantly 
 disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That 
 didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most 
 of
 it on the floor (or just let it hang there) to get it working at all 
 well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 
 times.
 Next I took a motorbike with studded snow tires up and got permission to
 turn down the power to the radio station.  That didn't fix the problem
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum 
 analyzer
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
 switch.  DC current or something.  So I started testing the cables that 
 run
 to the most problematic units.  Well now, look at that.  Bad cable.  In 
 fact
 there are three of them.  Hmmm, kinda strange though.  All three have 
 the
 exact same fault!  Oh well, better change them out anyway.  I ran three 
 new
 cable runs and just for kicks I tested one of them.  What the heck? 
 The
 new cable has the EXACT same fault as the old one!  Even though it 
 didn't
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I 
 was
 using indoor cat5 and didn't run lightning protection or ground 
 anything.
 Yeah I know, but remember that this has been there for a very long time 
 like
 this.  And as a guy with an electrical background I know that there are
 actually two ways to deal with stray electrical.  Grounding is one.
 Insulating is another  Anyway, I know it wasn't built to specs.

 I added some grounding and that didn't help at all.

 Yesterday I finally had one of the local wireless companies (Day 
 Wireless)
 that mainly does VHF radios, backhaul etc.  They also checked things 
 with
 the spectrum analyzer but couldn't find anything amiss.  I was able to
 duplicate the wiring fault for them (with my Ideal tester).  But 
 suddenly
 everything cleared right up!  Stuff was looking good, no cable fault 
 etc.
 Pings were looking good, devices were finally negotiating the 
 connections
 right etc.

 I called the radio station to ask if I could try turning the power down
 again to see if we see any change on the spectrum analyzer.  They said 
 they
 thought that I'd already done that because the showed the power was way
 down.  Turns out someone in the building had bumped a breaker and shut 
 down
 part of the transmitter!  Well

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Josh Luthman
With 100BASE-TX hardware, the raw bits (4 bits wide clocked at *25 MHz* at
the MII) go through 4B5B http://en.wikipedia.org/wiki/4B5B binary encoding
to generate a series of 0 and 1 symbols clocked at *125 MHz* symbol
ratehttp://en.wikipedia.org/wiki/Symbol_rate.
The 4B5B encoding provides DC equalization and spectrum shaping (see the
standard for details)[*citation
neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_needed
*]. Just as in the 100BASE-FX case, the bits are then transferred to the
physical medium attachment layer using
NRZIhttp://en.wikipedia.org/wiki/NRZIencoding. However, 100BASE-TX
introduces an additional, medium dependent
sublayer, which employs MLT-3 http://en.wikipedia.org/wiki/MLT-3 as a
final encoding of the data stream before transmission, resulting in a
maximum fundamental frequency of* 31.25 MHz*. The procedure is borrowed
from the ANSI X3.263 FDDI
http://en.wikipedia.org/wiki/FDDIspecifications, with minor
discrepancies.
[3] http://en.wikipedia.org/wiki/Fast_Ethernet#cite_note-mlt3-2

Source: http://en.wikipedia.org/wiki/Fast_Ethernet
Josh Luthman
Office: 937-552-2340
Direct: 937-552-2343
1100 Wayne St
Suite 1337
Troy, OH 45373

Those who don't understand UNIX are condemned to reinvent it, poorly.
--- Henry Spencer


On Thu, Jan 8, 2009 at 12:02 AM, Marlon K. Schafer o...@odessaoffice.comwrote:

 So far all I can find on the internet is that ethernet is at either 12.5 or
 31.25mhz.  NOT 350, that's gigE, not 10/100.

 Also, this tower is a 100' wooden pole.  Can't move anywhere really.
 marlon

 - Original Message -
 From: Adam Goodman a...@wispring.com
 To: WISPA General List wireless@wispa.org
 Sent: Wednesday, January 07, 2009 9:15 AM
 Subject: Re: [WISPA] FM radio station site strangeness


  It also sounds like there is a new leak in the waveguide. One more
  thing you might try is to move the cable from leg to leg on the tower
  so that you variable length sections that do not resonate at 350MHz or
  ~100MHz (FM transminssion).
 
 
  On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:
  We also colocate with an FM transmitter. Only 1300W though. we also
  had interference on our Ethernet lines. We solved it by moving radios
  away from the FM antenna (3 feet or so on a 90' tower) We also
  installed ferrits which helped (I actually used a conduit pipe).
  Grounding the cat5 helped too.
 
  I would think that if you find that you need more shielding. put all
  your cat5 cables in a conduit and install abreakout box at the top of
  the tower. If your area is prone to electrical storms (where isn't
  these days?!) you will at some point be very sorry you didn't grount
  (and well!!)
 
 
 
  On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer 
 o...@odessaoffice.com
  wrote:
  Hi All,
 
  I think we finally have this all figured out.  Now I just have to
 figure
  out
  how to fix it.
 
  We've been up there for over 6 years now.  It's certainly been a
  problematic
  site though.  Constant channel changes (we have 3 competitors a mile
  away
  and pick up hundreds of ap's from in town) are the norm.
 
  This fall (a month or two ago) one of the tenants left the building.
  This
  cleared out most of the hardware that was in there.  A little bit
 before
  that I replaced an Inscape Data and a smartBridges combo with a single
  MT
  access point, using one of the cables that had been working for one of
  the
  other two.
 
  About a week ago things started to really act up.  Multiple devices
 were
  having trouble.  I was able to catch it in the act finally.  This time
  the
  problem wasn't a wireless issue, the devices were constantly
  disconnecting
  and reconnecting at the switch level.
 
  I pulled the Cisco switch out and dropped in a Netgear unit.  That
  didn't
  fix it.  Next I put in a Digital Loggers rack mount reboot device.
  That
  wouldn't connect right either.
 
  I finally had to pull all of the hardware off of the shelf and set most
  of
  it on the floor (or just let it hang there) to get it working at all
  well.
  Still not perfect but better.
 
  I had by now hiked up there through sometimes knee deep snow 3 or 4
  times.
  Next I took a motorbike with studded snow tires up and got permission
 to
  turn down the power to the radio station.  That didn't fix the problem
  either.
 
  Next I borrowed a snowmobile and hauled some help and my spectrum
  analyzer
  up.  I was unable to see any signals that didn't belong.
 
  Next day, another hike up the hill.
 
  OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
  switch.  DC current or something.  So I started testing the cables that
  run
  to the most problematic units.  Well now, look at that.  Bad cable.  In
  fact
  there are three of them.  Hmmm, kinda strange though.  All three have
  the
  exact same fault!  Oh well, better change them out anyway.  I ran three
  new
  cable runs and just for kicks I tested one of them.  What the heck?
  The
  new

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Brian Rohrbacher




I installed a cat5 cable next to a guys police scanner one time and as
soon as I plugged the cable (lan cable from poe to computer) in the
police scanner stayed "keyed up" on 15o or 155 mhz as I remember.
Unplugged the cable and the scanner started scanning again, so I always
thought it was 150 some mhz.

Brian

Marlon K. Schafer wrote:

  So far all I can find on the internet is that ethernet is at either 12.5 or 
31.25mhz.  NOT 350, that's gigE, not 10/100.

Also, this tower is a 100' wooden pole.  Can't move anywhere really.
marlon

- Original Message - 
From: "Adam Goodman" a...@wispring.com
To: "WISPA General List" wireless@wispa.org
Sent: Wednesday, January 07, 2009 9:15 AM
Subject: Re: [WISPA] FM radio station site strangeness


  
  
It also sounds like there is a new leak in the waveguide. One more
thing you might try is to move the cable from leg to leg on the tower
so that you variable length sections that do not resonate at 350MHz or
~100MHz (FM transminssion).


On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:


  We also colocate with an FM transmitter. Only 1300W though. we also
had interference on our Ethernet lines. We solved it by moving radios
away from the FM antenna (3 feet or so on a 90' tower) We also
installed ferrits which helped (I actually used a conduit pipe).
Grounding the cat5 helped too.

I would think that if you find that you need more shielding. put all
your cat5 cables in a conduit and install abreakout box at the top of
the tower. If your area is prone to electrical storms (where isn't
these days?!) you will at some point be very sorry you didn't grount
(and well!!)



On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
wrote:
  
  
Hi All,

I think we finally have this all figured out.  Now I just have to figure 
out
how to fix it.

We've been up there for over 6 years now.  It's certainly been a 
problematic
site though.  Constant channel changes (we have 3 competitors a mile 
away
and pick up hundreds of ap's from in town) are the norm.

This fall (a month or two ago) one of the tenants left the building. 
This
cleared out most of the hardware that was in there.  A little bit before
that I replaced an Inscape Data and a smartBridges combo with a single 
MT
access point, using one of the cables that had been working for one of 
the
other two.

About a week ago things started to really act up.  Multiple devices were
having trouble.  I was able to catch it in the act finally.  This time 
the
problem wasn't a wireless issue, the devices were constantly 
disconnecting
and reconnecting at the switch level.

I pulled the Cisco switch out and dropped in a Netgear unit.  That 
didn't
fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
wouldn't connect right either.

I finally had to pull all of the hardware off of the shelf and set most 
of
it on the floor (or just let it hang there) to get it working at all 
well.
Still not perfect but better.

I had by now hiked up there through sometimes knee deep snow 3 or 4 
times.
Next I took a motorbike with studded snow tires up and got permission to
turn down the power to the radio station.  That didn't fix the problem
either.

Next I borrowed a snowmobile and hauled some help and my spectrum 
analyzer
up.  I was unable to see any signals that didn't belong.

Next day, another hike up the hill.

OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
switch.  DC current or something.  So I started testing the cables that 
run
to the most problematic units.  Well now, look at that.  Bad cable.  In 
fact
there are three of them.  Hmmm, kinda strange though.  All three have 
the
exact same fault!  Oh well, better change them out anyway.  I ran three 
new
cable runs and just for kicks I tested one of them.  What the heck? 
The
new cable has the EXACT same fault as the old one!  Even though it 
didn't
follow the exact same path as the old cables.

Man, this is sure looking like a problem caused by the radio station.  I 
was
using indoor cat5 and didn't run lightning protection or ground 
anything.
Yeah I know, but remember that this has been there for a very long time 
like
this.  And as a guy with an electrical background I know that there are
actually two ways to deal with stray electrical.  Grounding is one.
Insulating is another  Anyway, I know it wasn't built to specs.

I added some grounding and that didn't help at all.

Yesterday I finally had one of the local wireless companies (Day 
Wireless)
that mainly does VHF radios, backhaul etc.  They also checked things 
with
the spectrum analyzer but couldn't find anything amiss.  I was able to
duplicate the wiring fault for them (with my Ideal tester).  But 
suddenly
everything cleared right up!  Stuff was looking good, no cable fault 
etc.
Pings were looking good, devices were finally negotiating the 
connections
right etc.

I c

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Travis Johnson




Marlon,

It has taken us almost 10 years at our single FM radio station location
to figure out how to make things work at 100Mbps. This is one of the
worst stations I have ever seen or heard about. In the "generator" room
where we are located, the fluorescent light bulbs will actually glow
enough to see with the light switch turned off. Of course, this is a
100KW FM station operating at 99.1, so that doesn't help.

We started running shielded CAT5 cable (which we had done 8+ years
ago), but nobody told us we had to use shielded RJ45 ends as well AND
actually ground the drain wire to the outside of the RJ45 when crimping
the end. The other thing we discovered is we have to use shielded CAT5
patch cables (to go from the PoE injectors to the switch). The last
secret is if we are still having a problem with an ethernet link, by
changing the length of the patch cable (longer or shorter) that will
usually fix the problem.

Travis
Microserv

Marlon K. Schafer wrote:

  So far all I can find on the internet is that ethernet is at either 12.5 or 
31.25mhz.  NOT 350, that's gigE, not 10/100.

Also, this tower is a 100' wooden pole.  Can't move anywhere really.
marlon

- Original Message - 
From: "Adam Goodman" a...@wispring.com
To: "WISPA General List" wireless@wispa.org
Sent: Wednesday, January 07, 2009 9:15 AM
Subject: Re: [WISPA] FM radio station site strangeness


  
  
It also sounds like there is a new leak in the waveguide. One more
thing you might try is to move the cable from leg to leg on the tower
so that you variable length sections that do not resonate at 350MHz or
~100MHz (FM transminssion).


On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:


  We also colocate with an FM transmitter. Only 1300W though. we also
had interference on our Ethernet lines. We solved it by moving radios
away from the FM antenna (3 feet or so on a 90' tower) We also
installed ferrits which helped (I actually used a conduit pipe).
Grounding the cat5 helped too.

I would think that if you find that you need more shielding. put all
your cat5 cables in a conduit and install abreakout box at the top of
the tower. If your area is prone to electrical storms (where isn't
these days?!) you will at some point be very sorry you didn't grount
(and well!!)



On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
wrote:
  
  
Hi All,

I think we finally have this all figured out.  Now I just have to figure 
out
how to fix it.

We've been up there for over 6 years now.  It's certainly been a 
problematic
site though.  Constant channel changes (we have 3 competitors a mile 
away
and pick up hundreds of ap's from in town) are the norm.

This fall (a month or two ago) one of the tenants left the building. 
This
cleared out most of the hardware that was in there.  A little bit before
that I replaced an Inscape Data and a smartBridges combo with a single 
MT
access point, using one of the cables that had been working for one of 
the
other two.

About a week ago things started to really act up.  Multiple devices were
having trouble.  I was able to catch it in the act finally.  This time 
the
problem wasn't a wireless issue, the devices were constantly 
disconnecting
and reconnecting at the switch level.

I pulled the Cisco switch out and dropped in a Netgear unit.  That 
didn't
fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
wouldn't connect right either.

I finally had to pull all of the hardware off of the shelf and set most 
of
it on the floor (or just let it hang there) to get it working at all 
well.
Still not perfect but better.

I had by now hiked up there through sometimes knee deep snow 3 or 4 
times.
Next I took a motorbike with studded snow tires up and got permission to
turn down the power to the radio station.  That didn't fix the problem
either.

Next I borrowed a snowmobile and hauled some help and my spectrum 
analyzer
up.  I was unable to see any signals that didn't belong.

Next day, another hike up the hill.

OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
switch.  DC current or something.  So I started testing the cables that 
run
to the most problematic units.  Well now, look at that.  Bad cable.  In 
fact
there are three of them.  Hmmm, kinda strange though.  All three have 
the
exact same fault!  Oh well, better change them out anyway.  I ran three 
new
cable runs and just for kicks I tested one of them.  What the heck? 
The
new cable has the EXACT same fault as the old one!  Even though it 
didn't
follow the exact same path as the old cables.

Man, this is sure looking like a problem caused by the radio station.  I 
was
using indoor cat5 and didn't run lightning protection or ground 
anything.
Yeah I know, but remember that this has been there for a very long time 
like
this.  And as a guy with an electrical background I know that there are
actually two ways

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Marlon K. Schafer
Not yet.  I've got some on the way thought.
marlon

- Original Message - 
From: rea...@muddyfrogwater.us
To: WISPA General List wireless@wispa.org
Sent: Wednesday, January 07, 2009 1:08 PM
Subject: Re: [WISPA] FM radio station site strangeness


 Do you have the shielded cable?

 Mark



 
 insert witty tagline here

 - Original Message - 
 From: Marlon K. Schafer o...@odessaoffice.com
 To: WISPA General List wireless@wispa.org
 Cc: isp-wirel...@isp-wireless.com
 Sent: Wednesday, January 07, 2009 7:47 AM
 Subject: [WISPA] FM radio station site strangeness


 Hi All,

 I think we finally have this all figured out.  Now I just have to figure
 out
 how to fix it.

 We've been up there for over 6 years now.  It's certainly been a
 problematic
 site though.  Constant channel changes (we have 3 competitors a mile away
 and pick up hundreds of ap's from in town) are the norm.

 This fall (a month or two ago) one of the tenants left the building. 
 This
 cleared out most of the hardware that was in there.  A little bit before
 that I replaced an Inscape Data and a smartBridges combo with a single MT
 access point, using one of the cables that had been working for one of 
 the
 other two.

 About a week ago things started to really act up.  Multiple devices were
 having trouble.  I was able to catch it in the act finally.  This time 
 the
 problem wasn't a wireless issue, the devices were constantly 
 disconnecting
 and reconnecting at the switch level.

 I pulled the Cisco switch out and dropped in a Netgear unit.  That didn't
 fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
 wouldn't connect right either.

 I finally had to pull all of the hardware off of the shelf and set most 
 of
 it on the floor (or just let it hang there) to get it working at all 
 well.
 Still not perfect but better.

 I had by now hiked up there through sometimes knee deep snow 3 or 4 
 times.
 Next I took a motorbike with studded snow tires up and got permission to
 turn down the power to the radio station.  That didn't fix the problem
 either.

 Next I borrowed a snowmobile and hauled some help and my spectrum 
 analyzer
 up.  I was unable to see any signals that didn't belong.

 Next day, another hike up the hill.

 OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
 switch.  DC current or something.  So I started testing the cables that
 run
 to the most problematic units.  Well now, look at that.  Bad cable.  In
 fact
 there are three of them.  Hmmm, kinda strange though.  All three have the
 exact same fault!  Oh well, better change them out anyway.  I ran three
 new
 cable runs and just for kicks I tested one of them.  What the heck?
 The
 new cable has the EXACT same fault as the old one!  Even though it didn't
 follow the exact same path as the old cables.

 Man, this is sure looking like a problem caused by the radio station.  I
 was
 using indoor cat5 and didn't run lightning protection or ground anything.
 Yeah I know, but remember that this has been there for a very long time
 like
 this.  And as a guy with an electrical background I know that there are
 actually two ways to deal with stray electrical.  Grounding is one.
 Insulating is another  Anyway, I know it wasn't built to specs.

 I added some grounding and that didn't help at all.

 Yesterday I finally had one of the local wireless companies (Day 
 Wireless)
 that mainly does VHF radios, backhaul etc.  They also checked things with
 the spectrum analyzer but couldn't find anything amiss.  I was able to
 duplicate the wiring fault for them (with my Ideal tester).  But suddenly
 everything cleared right up!  Stuff was looking good, no cable fault etc.
 Pings were looking good, devices were finally negotiating the connections
 right etc.

 I called the radio station to ask if I could try turning the power down
 again to see if we see any change on the spectrum analyzer.  They said
 they
 thought that I'd already done that because the showed the power was way
 down.  Turns out someone in the building had bumped a breaker and shut
 down
 part of the transmitter!  Well, we got all of that figured out and guess
 what.  All of the problems came right back!  I then turned the power back
 down and they cleared up.

 Tip for you guys, dropping an 18,000 watt system down by even 60% of it's
 normal output isn't always enough.  We had to drop down to 10 to 20% to
 get
 the problems to clear up.  The guys from Day Wireless had some small
 ferrite
 beads with them so we stuck them onto the cables.  Put the beads on and
 the
 radios would negotiate at 100full.  Take them off and they'd drop right
 back
 to 100 half.  Duplicatable all day long.

 S, current theory is that the radio station is screwing up my cat5
 connections.  The fact that the building has less hardware in it and we
 have
 more snow up there than normal has probably caused some different eddy
 currents or multipath

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Marlon K. Schafer
OK, can we put this in plain English?  What freq. does 100meg ethernet in 
full or half duplex
marlon

- Original Message - 
From: Josh Luthman j...@imaginenetworksllc.com
To: WISPA General List wireless@wispa.org
Sent: Wednesday, January 07, 2009 9:07 PM
Subject: Re: [WISPA] FM radio station site strangeness


 With 100BASE-TX hardware, the raw bits (4 bits wide clocked at *25 MHz* at
 the MII) go through 4B5B http://en.wikipedia.org/wiki/4B5B binary 
 encoding
 to generate a series of 0 and 1 symbols clocked at *125 MHz* symbol
 ratehttp://en.wikipedia.org/wiki/Symbol_rate.
 The 4B5B encoding provides DC equalization and spectrum shaping (see the
 standard for details)[*citation
 neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_needed
 *]. Just as in the 100BASE-FX case, the bits are then transferred to the
 physical medium attachment layer using
 NRZIhttp://en.wikipedia.org/wiki/NRZIencoding. However, 100BASE-TX
 introduces an additional, medium dependent
 sublayer, which employs MLT-3 http://en.wikipedia.org/wiki/MLT-3 as a
 final encoding of the data stream before transmission, resulting in a
 maximum fundamental frequency of* 31.25 MHz*. The procedure is borrowed
 from the ANSI X3.263 FDDI
 http://en.wikipedia.org/wiki/FDDIspecifications, with minor
 discrepancies.
 [3] http://en.wikipedia.org/wiki/Fast_Ethernet#cite_note-mlt3-2

 Source: http://en.wikipedia.org/wiki/Fast_Ethernet
 Josh Luthman
 Office: 937-552-2340
 Direct: 937-552-2343
 1100 Wayne St
 Suite 1337
 Troy, OH 45373

 Those who don't understand UNIX are condemned to reinvent it, poorly.
 --- Henry Spencer


 On Thu, Jan 8, 2009 at 12:02 AM, Marlon K. Schafer 
 o...@odessaoffice.comwrote:

 So far all I can find on the internet is that ethernet is at either 12.5 
 or
 31.25mhz.  NOT 350, that's gigE, not 10/100.

 Also, this tower is a 100' wooden pole.  Can't move anywhere really.
 marlon

 - Original Message -
 From: Adam Goodman a...@wispring.com
 To: WISPA General List wireless@wispa.org
 Sent: Wednesday, January 07, 2009 9:15 AM
 Subject: Re: [WISPA] FM radio station site strangeness


  It also sounds like there is a new leak in the waveguide. One more
  thing you might try is to move the cable from leg to leg on the tower
  so that you variable length sections that do not resonate at 350MHz or
  ~100MHz (FM transminssion).
 
 
  On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com 
  wrote:
  We also colocate with an FM transmitter. Only 1300W though. we also
  had interference on our Ethernet lines. We solved it by moving radios
  away from the FM antenna (3 feet or so on a 90' tower) We also
  installed ferrits which helped (I actually used a conduit pipe).
  Grounding the cat5 helped too.
 
  I would think that if you find that you need more shielding. put all
  your cat5 cables in a conduit and install abreakout box at the top of
  the tower. If your area is prone to electrical storms (where isn't
  these days?!) you will at some point be very sorry you didn't grount
  (and well!!)
 
 
 
  On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer 
 o...@odessaoffice.com
  wrote:
  Hi All,
 
  I think we finally have this all figured out.  Now I just have to
 figure
  out
  how to fix it.
 
  We've been up there for over 6 years now.  It's certainly been a
  problematic
  site though.  Constant channel changes (we have 3 competitors a mile
  away
  and pick up hundreds of ap's from in town) are the norm.
 
  This fall (a month or two ago) one of the tenants left the building.
  This
  cleared out most of the hardware that was in there.  A little bit
 before
  that I replaced an Inscape Data and a smartBridges combo with a 
  single
  MT
  access point, using one of the cables that had been working for one 
  of
  the
  other two.
 
  About a week ago things started to really act up.  Multiple devices
 were
  having trouble.  I was able to catch it in the act finally.  This 
  time
  the
  problem wasn't a wireless issue, the devices were constantly
  disconnecting
  and reconnecting at the switch level.
 
  I pulled the Cisco switch out and dropped in a Netgear unit.  That
  didn't
  fix it.  Next I put in a Digital Loggers rack mount reboot device.
  That
  wouldn't connect right either.
 
  I finally had to pull all of the hardware off of the shelf and set 
  most
  of
  it on the floor (or just let it hang there) to get it working at all
  well.
  Still not perfect but better.
 
  I had by now hiked up there through sometimes knee deep snow 3 or 4
  times.
  Next I took a motorbike with studded snow tires up and got permission
 to
  turn down the power to the radio station.  That didn't fix the 
  problem
  either.
 
  Next I borrowed a snowmobile and hauled some help and my spectrum
  analyzer
  up.  I was unable to see any signals that didn't belong.
 
  Next day, another hike up the hill.
 
  OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
  switch.  DC current

Re: [WISPA] FM radio station site strangeness

2009-01-07 Thread Marlon K. Schafer
I thought I'd try that too.
marlon

  - Original Message - 
  From: Travis Johnson 
  To: WISPA General List 
  Sent: Wednesday, January 07, 2009 9:12 PM
  Subject: Re: [WISPA] FM radio station site strangeness


  Marlon,

  It has taken us almost 10 years at our single FM radio station location to 
figure out how to make things work at 100Mbps. This is one of the worst 
stations I have ever seen or heard about. In the generator room where we are 
located, the fluorescent light bulbs will actually glow enough to see with the 
light switch turned off. Of course, this is a 100KW FM station operating at 
99.1, so that doesn't help.

  We started running shielded CAT5 cable (which we had done 8+ years ago), but 
nobody told us we had to use shielded RJ45 ends as well AND actually ground the 
drain wire to the outside of the RJ45 when crimping the end. The other thing we 
discovered is we have to use shielded CAT5 patch cables (to go from the PoE 
injectors to the switch). The last secret is if we are still having a problem 
with an ethernet link, by changing the length of the patch cable (longer or 
shorter) that will usually fix the problem.

  Travis
  Microserv

  Marlon K. Schafer wrote: 
So far all I can find on the internet is that ethernet is at either 12.5 or 
31.25mhz.  NOT 350, that's gigE, not 10/100.

Also, this tower is a 100' wooden pole.  Can't move anywhere really.
marlon

- Original Message - 
From: Adam Goodman a...@wispring.com
To: WISPA General List wireless@wispa.org
Sent: Wednesday, January 07, 2009 9:15 AM
Subject: Re: [WISPA] FM radio station site strangeness


  It also sounds like there is a new leak in the waveguide. One more
thing you might try is to move the cable from leg to leg on the tower
so that you variable length sections that do not resonate at 350MHz or
~100MHz (FM transminssion).


On Wed, Jan 7, 2009 at 11:16 AM, Adam Goodman a...@wispring.com wrote:
We also colocate with an FM transmitter. Only 1300W though. we also
had interference on our Ethernet lines. We solved it by moving radios
away from the FM antenna (3 feet or so on a 90' tower) We also
installed ferrits which helped (I actually used a conduit pipe).
Grounding the cat5 helped too.

I would think that if you find that you need more shielding. put all
your cat5 cables in a conduit and install abreakout box at the top of
the tower. If your area is prone to electrical storms (where isn't
these days?!) you will at some point be very sorry you didn't grount
(and well!!)



On Wed, Jan 7, 2009 at 10:47 AM, Marlon K. Schafer o...@odessaoffice.com 
wrote:
  Hi All,

I think we finally have this all figured out.  Now I just have to figure 
out
how to fix it.

We've been up there for over 6 years now.  It's certainly been a 
problematic
site though.  Constant channel changes (we have 3 competitors a mile 
away
and pick up hundreds of ap's from in town) are the norm.

This fall (a month or two ago) one of the tenants left the building. 
This
cleared out most of the hardware that was in there.  A little bit before
that I replaced an Inscape Data and a smartBridges combo with a single 
MT
access point, using one of the cables that had been working for one of 
the
other two.

About a week ago things started to really act up.  Multiple devices were
having trouble.  I was able to catch it in the act finally.  This time 
the
problem wasn't a wireless issue, the devices were constantly 
disconnecting
and reconnecting at the switch level.

I pulled the Cisco switch out and dropped in a Netgear unit.  That 
didn't
fix it.  Next I put in a Digital Loggers rack mount reboot device.  That
wouldn't connect right either.

I finally had to pull all of the hardware off of the shelf and set most 
of
it on the floor (or just let it hang there) to get it working at all 
well.
Still not perfect but better.

I had by now hiked up there through sometimes knee deep snow 3 or 4 
times.
Next I took a motorbike with studded snow tires up and got permission to
turn down the power to the radio station.  That didn't fix the problem
either.

Next I borrowed a snowmobile and hauled some help and my spectrum 
analyzer
up.  I was unable to see any signals that didn't belong.

Next day, another hike up the hill.

OK, maybe a cat 5 cable went bad and I'm getting backfeed through the
switch.  DC current or something.  So I started testing the cables that 
run
to the most problematic units.  Well now, look at that.  Bad cable.  In 
fact
there are three of them.  Hmmm, kinda strange though.  All three have 
the
exact same fault!  Oh well, better change them out anyway.  I ran three 
new
cable runs and just for kicks I tested one of them.  What the heck? 
The
new cable has the EXACT same fault as the old one!  Even though it 
didn't
follow the exact same path as the old cables.

Man, this is sure looking like a problem caused by the radio station.  I 
was
using indoor cat5 and didn't run lightning protection or ground 
anything