Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Tom DeReggi]




I agree with your concern. Most likely the person 
doing the testing is the person doing the sale of the Redline?
 
 
Tom DeReggiRapidDSL & Wireless, IncIntAirNet- Fixed Wireless 
Broadband
 
 

  - Original Message - 
  From: 
  JohnnyO 
  To: WISPA General List 
  Sent: Friday, February 10, 2006 8:44 
  AM
  Subject: RE: [WISPA] Flawed Spectrum 
  Analysis (I think!)
  I think what you thought was RG6 was actually RG59 - Redline is 
  a pretty clean platform so I don't think too many issues will arise from the 
  deployment of that platform in your area.JohnnyOOn Fri, 
  2006-02-10 at 07:31 -0600, Cliff Leboeuf wrote: 
  
Thanks for all of the 
  feedback. For clarification, the LMR400 cable was 140 feet and was the 
  only cable that connected the analyzer to the 
  antenna. I am familiar with the IDU and ODU configuration of the 
  Redline equipment. This test was to see what 5.8 RF was present. The customer 
  plans to deploy a series of P2P and P2Mp radios in the same coverage area 
  as two other towers that have 5.8 deployed.My climber was familiar with the other tower 
  locations, and wanted to ‘prove’ other RF was in the same area, and that 
  the Redline P2Mp has the potential to affect these other towers 
  adversely.
Though I have not seen their conclusion, I am 
  not confident in their methods; and the fact that I believe they just want 
  to install. Once they are functional, they are ‘outta here.’ Then, the 
  customer will be left to mitigate any issues that could easily be avoided, 
  or minimized, by using other frequencies. This is a public safety entity 
  and should be using the 4.9Ghz frequency, but I think Redline has this 
  project wrapped up and since they don’t make 4.9Ghz equipment, they are 
  ‘forcing’ the 5.8Ghz and are resisting my ideas tooth and 
  nail. Why create a potential for problems when you know it can be 
  avoided…That the government though! J - Cliff
  
  

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[JohnnyO]

On Fri, 2006-02-10 at 10:17 -0500, Bob Moldashel wrote:


Dustin Jurman wrote:

>If the spectrum analyzer is left in place for a period of time and setup
>with "peak hold" you will quickly find that radio that is used at the end of
>the day. It still speaks, handshakes and more. 
>  
>

I don't know about you but I'm not about to leave a spectrum analyzer 
180' up a tower for any period of time.

>Just setting up big shots and blowing people out is bad business for
>everyone. 
>
I am not saying to blow people out of the water with power. I am saying 
to make sure you have ample power and gain to supply a solid signal. 
Running at -78 on a link is not a solid signal in my mind.  We only use 
equipment where we can control the power. We don't run full bore unlike 
alot of WISP operators. We don't plug radios like Motorola Canopy units 
into omni's. And my opinion is if I blow that guy off the air, so be 
it.  It was not properly engineered to begin with. It was finacially 
engineered to get by cheap.



I would have to agree here with Bob - Anyone engineering their links properly are going to use the best antennas with the narrowest beamwidth possible to mitigate any current or future interference. In my mind, an antenna that has 8deg beamwidth for a critical link is absolutely ignorant.





>If the customer wants a quality shot then there should be no
>problem doing a spectrum analysis, freq decision and installation shortly
>after.  
>  
>

But the point is moot if Johnny O comes along on your channel tomorrow 
and blows you off the air (I am only using him as an example).  Then the 
customer is all pissy because he spent money for spectrum analysis that 
was totally moot.


And this again is where the man with the better antennas will win hands down everytime. Even with a noisly spectrum in the area, lf you're using good antennas, chances are you'll knock someone down before they knock you down. It doesn't matter who was where first, what matters is that you run your own business or that of your customers with the most attention to mitigation of interference.

JohnnyO





>I agree it's only good for a certain amount of time, but if the customer
>wants a reliable shot then due diligence is better than chance luck.  
>  
>

I don't think a properly engineered link is chance luck. We don't just 
pick a channel out of thin air and go with it. Alot of engineering goes 
into it. Spectrum analysis is just not a factor 99.999 percent of the time.

-B-

>Dustin 
>  
>


-- 
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell





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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Cliff Leboeuf]

Bob,

I understand you comments and totally agree.

They have been informed that any analysis is just a 'snapshot' of the
conditions at the time takes. Just like a picture from a camera.

Thanks again,
Cliff


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bob Moldashel
Sent: Friday, February 10, 2006 10:09 AM
To: WISPA General List
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)

Cliff Leboeuf wrote:

>Dustin, thanks for the encouraging support of my efforts. 
>
>Since we have been hired for part of this project, I believe it is my
>RESPONSIBILITY to point out any known issues to the customer; and, it
is
>my responsibility to back up my concerns with hard date, not just 'my
>feelings.' In the event that the data doesn't show what I know to be in
>the area, I will at lease be on record for making them aware of other
>5Ghz RF in the overlapping areas.
>
>I am interested in any information that you are willing to supply for
my
>education.
>
>Again, thanks for all of the feedback and discussion in my topic.
>- Cliff
>
>  
>
Cliff,

I can appreciate that you want to give your customer hard data. That is 
understandable. But you also need to have a list of conditions and 
presumptions as well as exceptions.

Make sure the customer understands that the spectrum analysis is only 
good for the date it was taken and does not guarantee interference free 
operation in the future. The last thing you need is to have the customer

pay you to do an analysis today and deploy 90 days from now only to find

issues.

Otherwise...good luck with your customer.

-B-

-- 
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Marlon K. Schafer (509) 982-2181]

- Original Message - 
From: "Bob Moldashel" <[EMAIL PROTECTED]>

To: "WISPA General List" 
Sent: Friday, February 10, 2006 8:08 AM
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)



Cliff Leboeuf wrote:


Dustin, thanks for the encouraging support of my efforts.
Since we have been hired for part of this project, I believe it is my
RESPONSIBILITY to point out any known issues to the customer; and, it is
my responsibility to back up my concerns with hard date, not just 'my
feelings.' In the event that the data doesn't show what I know to be in
the area, I will at lease be on record for making them aware of other
5Ghz RF in the overlapping areas.

I am interested in any information that you are willing to supply for my
education.

Again, thanks for all of the feedback and discussion in my topic.
- Cliff



Cliff,

I can appreciate that you want to give your customer hard data. That is 
understandable. But you also need to have a list of conditions and 
presumptions as well as exceptions.


Make sure the customer understands that the spectrum analysis is only good 
for the date it was taken and does not guarantee interference free 
operation in the future. The last thing you need is to have the customer 
pay you to do an analysis today and deploy 90 days from now only to find 
issues.


Great point.  We ALWAYS do this.  And we also ALWAYS do a spectrum analysys. 
Sure we'll miss things, there's a LOT out there these days.  Conditions also 
change, sometimes between when we do the SA check and deploy hardware. 
However, we USUALLY learn a great deal about what's an option and what's not 
ahead of time.  It's pretty rare that we miss enough that we have to back up 
and start all over with a system design.


And I think that you can readily admit that there is a HUGE difference 
between running ptp links and ptmp links as far as interference exposure is 
concerned.  Most of our stuff is ptmp so we HAVE to look at much greater 
areas.


I DO know you and the amazing things you've done.  I still say you are a bad 
boy!  (in more ways than one, cackle)


Cliff, you are very much on the right track.  You need to tell them what you 
know so they can make informed dicisions.  I'd rather loose a customer 
because they didn't want to hear what I had to say than keep one that's not 
happy.


marlon



Otherwise...good luck with your customer.

-B-

--
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Bob Moldashel]

Marlon K. Schafer (509) 982-2181 wrote:


I totally agree with Dustin here.

Hanging them without looking first is akin to running  a stop sign.  
You'll probably be fine, most of the time.  But..


It doesn't take long to look.

Bob's right, things can and almost always do get missed.  Dustin is 
also right though, one should find out as much as possible and make an 
informed decision as to what freq/channel to use.


Bob, I'm shocked to hear you say you don't look before you leap!  oy!



You crack me up!  :-)


And telling people to use high power radios.  Yikes.  Dude.  People 
should use as much power as it takes to do that job, not a drop more!  
ESPECIALLY in urban markets.  All a 40 dB fade margin does is cause 
interference 20 miles (literally) down the road.


Augh! Go back and re-read what I wrote.  Let me know if you need any 
help.  :-P




I sure wish the FCC would put an APC requirement on all future radio 
designs.  Then we could have our high power radios and avoid the rats 
nest that always eventually comes with using higher power than what's 
needed.


For a point of reference.  I have a WiFi based 21 mile ptp link that 
gets 2 megs of throughput.  These are only 17dB INDOOR radios, short 
lmr400 runs and 24dB grid antennas.


Marlon
(509) 982-2181   Equipment sales
(408) 907-6910 (Vonage)Consulting services
42846865 (icq)And I run my own wisp!
64.146.146.12 (net meeting)
www.odessaoffice.com/wireless
www.odessaoffice.com/marlon/cam




--
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Marlon K. Schafer (509) 982-2181]

I totally agree with Dustin here.

Hanging them without looking first is akin to running  a stop sign.  You'll 
probably be fine, most of the time.  But..


It doesn't take long to look.

Bob's right, things can and almost always do get missed.  Dustin is also 
right though, one should find out as much as possible and make an informed 
decision as to what freq/channel to use.


Bob, I'm shocked to hear you say you don't look before you leap!  oy!  And 
telling people to use high power radios.  Yikes.  Dude.  People should use 
as much power as it takes to do that job, not a drop more!  ESPECIALLY in 
urban markets.  All a 40 dB fade margin does is cause interference 20 miles 
(literally) down the road.


I sure wish the FCC would put an APC requirement on all future radio 
designs.  Then we could have our high power radios and avoid the rats nest 
that always eventually comes with using higher power than what's needed.


For a point of reference.  I have a WiFi based 21 mile ptp link that gets 2 
megs of throughput.  These are only 17dB INDOOR radios, short lmr400 runs 
and 24dB grid antennas.


Marlon
(509) 982-2181   Equipment sales
(408) 907-6910 (Vonage)Consulting services
42846865 (icq)And I run my own wisp!
64.146.146.12 (net meeting)
www.odessaoffice.com/wireless
www.odessaoffice.com/marlon/cam



- Original Message - 
From: "Dustin Jurman" <[EMAIL PROTECTED]>

To: "'WISPA General List'" 
Sent: Friday, February 10, 2006 7:01 AM
Subject: RE: [WISPA] Flawed Spectrum Analysis (I think!)



If the spectrum analyzer is left in place for a period of time and setup
with "peak hold" you will quickly find that radio that is used at the end 
of

the day. It still speaks, handshakes and more.

Just setting up big shots and blowing people out is bad business for
everyone. If the customer wants a quality shot then there should be no
problem doing a spectrum analysis, freq decision and installation shortly
after.

I agree it's only good for a certain amount of time, but if the customer
wants a reliable shot then due diligence is better than chance luck.

Dustin

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bob Moldashel
Sent: Friday, February 10, 2006 9:49 AM
To: WISPA General List
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)

AUGH!


This whole thread..

Some have touched on pieces of it but how about this summary..

The Redline is a two piece radio.  It does not send 5 Ghz up the cable.
It sends an IF frequency which is lower and more forgiving as well as
power to operate the outdoor unit. The Redline as pointed out does not
have a spectrum analyzer (in the versions I have worked with).  As such
they probably just checked for RSL on any or all channels.  This is not
a spectrum analysis by any means. The Redline equipment is great
equipment but it is not a spectrum analyzer.

A spectrum analysis is flawed in almost any case really because it is
only good at the time of the testing and along the path of the test. You
really will only see stronger signals with an omni. But you can still
have your signal killed if someone is using directional antennas and
looking down your path. There is a big difference from 8 dB to 29 dB.

The other case is a 5 Ghz. system in place that only is used at the end
of the day or does "dumps' at certain times.  Unlike a full duplex radio
like a Proxim Tsunami that is talking all the time regardless of the
received signal, you may only see a signal when the associated equipment
is passing data.

In my book you can't do "reliable spectrum analysis" with any radio or
assocaited radio card. Yes, there are systems out there that work really
well but I would not be willing to bet my reputation on most.  Will they
get you by in most cases???  Sure.
But...

To answer your question..Yes, the spectrum analysis was flawed.

Personally...we never do spectrum analysis.  It causes more headaches
than what it is worth IMHO.  Is it great for finding interference??  Sure.

I have installed links in lower Manhattan (nearly 70 to date on
unlicensed 5 Ghz), Washington DC and Boston without ever needing a
spectrum analysis. All these locations are RF hotbeds.

A few things to consider. Use a radio with a very good C/I value. Use 2'
or larger antennas to keep the beamwidth tight. Use radios that are
capable of 5 or 10 Mhz. channels.  Use radios with high RF power output.
If you need to run transmission line to the radio, use the right stuff
for the job. LMR400 and 5 Ghz. are not my considered options unless the
cable length is less than 24".  We use LMR600 up to 100' and 5/8" heliax
after that. make sure the radio has a good receiver threshold. Wherever

Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Bob Moldashel]

Cliff Leboeuf wrote:

Dustin, thanks for the encouraging support of my efforts. 


Since we have been hired for part of this project, I believe it is my
RESPONSIBILITY to point out any known issues to the customer; and, it is
my responsibility to back up my concerns with hard date, not just 'my
feelings.' In the event that the data doesn't show what I know to be in
the area, I will at lease be on record for making them aware of other
5Ghz RF in the overlapping areas.

I am interested in any information that you are willing to supply for my
education.

Again, thanks for all of the feedback and discussion in my topic.
- Cliff

 


Cliff,

I can appreciate that you want to give your customer hard data. That is 
understandable. But you also need to have a list of conditions and 
presumptions as well as exceptions.


Make sure the customer understands that the spectrum analysis is only 
good for the date it was taken and does not guarantee interference free 
operation in the future. The last thing you need is to have the customer 
pay you to do an analysis today and deploy 90 days from now only to find 
issues.


Otherwise...good luck with your customer.

-B-

--
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Bob Moldashel]

Dustin Jurman wrote:


Takes no more than a few minutes to perform a peak hold Bob,  maybe you
should get one and play with it a bit.  It's a very powerful tool and I
think your opinion will change.   
 



LOL.Trust me.  I know all about peak hold.  And my opinion doesn't 
change.




I agree that we have two different schools of thought. 
1. Plan the play, play the plan.

2. Show up for the game.
 



Which one am I



Cliff was doing the right thing by doing a spectrum analysis, esp knowing
that he was going to go trough some existing equipment.  Anything short of
that would be irresponsible.  I would say to Cliff that if they cannot
produce results from the analyzer, graphs and charts than it's worthless and
done improperly,  just because you have an analyzer doesn't mean you know
how to use it.  

 



Dustin...I know you don't know my background and for that I can 
understand your reply.  It is not "irresponsible" to do a link without 
doing a spectrum analysis. If it gives you a comfort level that you 
enjoy or require, thats fine.  I can live with that.


I need to go take a nap now.  This whole thread made me tired.

:-)

-B-





If it's helpful I will post some shots to a website if Cliff thinks that it
is helpful.  


Dustin Jurman
Rapid Systems Corporation
1211 North Westshore Blvd
Tampa, FL 33607
813--232-4887
Building Better Infrastructure!



-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bob Moldashel
Sent: Friday, February 10, 2006 10:17 AM
To: WISPA General List
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)

Dustin Jurman wrote:

 


If the spectrum analyzer is left in place for a period of time and setup
with "peak hold" you will quickly find that radio that is used at the end
   


of
 

the day. It still speaks, handshakes and more. 



   



I don't know about you but I'm not about to leave a spectrum analyzer 
180' up a tower for any period of time.


 


Just setting up big shots and blowing people out is bad business for
everyone. 

   

I am not saying to blow people out of the water with power. I am saying 
to make sure you have ample power and gain to supply a solid signal. 
Running at -78 on a link is not a solid signal in my mind.  We only use 
equipment where we can control the power. We don't run full bore unlike 
alot of WISP operators. We don't plug radios like Motorola Canopy units 
into omni's. And my opinion is if I blow that guy off the air, so be 
it.  It was not properly engineered to begin with. It was finacially 
engineered to get by cheap.




 


If the customer wants a quality shot then there should be no
problem doing a spectrum analysis, freq decision and installation shortly
after.  



   



But the point is moot if Johnny O comes along on your channel tomorrow 
and blows you off the air (I am only using him as an example).  Then the 
customer is all pissy because he spent money for spectrum analysis that 
was totally moot.


 


I agree it's only good for a certain amount of time, but if the customer
wants a reliable shot then due diligence is better than chance luck.  



   



I don't think a properly engineered link is chance luck. We don't just 
pick a channel out of thin air and go with it. Alot of engineering goes 
into it. Spectrum analysis is just not a factor 99.999 percent of the time.


-B-

 

Dustin 



   




 




--
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Cliff Leboeuf]

Dustin, thanks for the encouraging support of my efforts. 

Since we have been hired for part of this project, I believe it is my
RESPONSIBILITY to point out any known issues to the customer; and, it is
my responsibility to back up my concerns with hard date, not just 'my
feelings.' In the event that the data doesn't show what I know to be in
the area, I will at lease be on record for making them aware of other
5Ghz RF in the overlapping areas.

I am interested in any information that you are willing to supply for my
education.

Again, thanks for all of the feedback and discussion in my topic.
- Cliff


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Dustin Jurman
Sent: Friday, February 10, 2006 9:42 AM
To: 'WISPA General List'
Subject: RE: [WISPA] Flawed Spectrum Analysis (I think!)

Takes no more than a few minutes to perform a peak hold Bob,  maybe you
should get one and play with it a bit.  It's a very powerful tool and I
think your opinion will change.   

I agree that we have two different schools of thought. 
1. Plan the play, play the plan.
2. Show up for the game.

Cliff was doing the right thing by doing a spectrum analysis, esp
knowing
that he was going to go trough some existing equipment.  Anything short
of
that would be irresponsible.  I would say to Cliff that if they cannot
produce results from the analyzer, graphs and charts than it's worthless
and
done improperly,  just because you have an analyzer doesn't mean you
know
how to use it.  

If it's helpful I will post some shots to a website if Cliff thinks that
it
is helpful.  

Dustin Jurman
Rapid Systems Corporation
1211 North Westshore Blvd
Tampa, FL 33607
813--232-4887
Building Better Infrastructure!



-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bob Moldashel
Sent: Friday, February 10, 2006 10:17 AM
To: WISPA General List
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)

Dustin Jurman wrote:

>If the spectrum analyzer is left in place for a period of time and
setup
>with "peak hold" you will quickly find that radio that is used at the
end
of
>the day. It still speaks, handshakes and more. 
>  
>

I don't know about you but I'm not about to leave a spectrum analyzer 
180' up a tower for any period of time.

>Just setting up big shots and blowing people out is bad business for
>everyone. 
>
I am not saying to blow people out of the water with power. I am saying 
to make sure you have ample power and gain to supply a solid signal. 
Running at -78 on a link is not a solid signal in my mind.  We only use 
equipment where we can control the power. We don't run full bore unlike 
alot of WISP operators. We don't plug radios like Motorola Canopy units 
into omni's. And my opinion is if I blow that guy off the air, so be 
it.  It was not properly engineered to begin with. It was finacially 
engineered to get by cheap.



>If the customer wants a quality shot then there should be no
>problem doing a spectrum analysis, freq decision and installation
shortly
>after.  
>  
>

But the point is moot if Johnny O comes along on your channel tomorrow 
and blows you off the air (I am only using him as an example).  Then the

customer is all pissy because he spent money for spectrum analysis that 
was totally moot.

>I agree it's only good for a certain amount of time, but if the
customer
>wants a reliable shot then due diligence is better than chance luck.  
>  
>

I don't think a properly engineered link is chance luck. We don't just 
pick a channel out of thin air and go with it. Alot of engineering goes 
into it. Spectrum analysis is just not a factor 99.999 percent of the
time.

-B-

>Dustin 
>  
>


-- 
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell




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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Dustin Jurman]

Takes no more than a few minutes to perform a peak hold Bob,  maybe you
should get one and play with it a bit.  It's a very powerful tool and I
think your opinion will change.   

I agree that we have two different schools of thought. 
1. Plan the play, play the plan.
2. Show up for the game.

Cliff was doing the right thing by doing a spectrum analysis, esp knowing
that he was going to go trough some existing equipment.  Anything short of
that would be irresponsible.  I would say to Cliff that if they cannot
produce results from the analyzer, graphs and charts than it's worthless and
done improperly,  just because you have an analyzer doesn't mean you know
how to use it.  

If it's helpful I will post some shots to a website if Cliff thinks that it
is helpful.  

Dustin Jurman
Rapid Systems Corporation
1211 North Westshore Blvd
Tampa, FL 33607
813--232-4887
Building Better Infrastructure!



-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bob Moldashel
Sent: Friday, February 10, 2006 10:17 AM
To: WISPA General List
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)

Dustin Jurman wrote:

>If the spectrum analyzer is left in place for a period of time and setup
>with "peak hold" you will quickly find that radio that is used at the end
of
>the day. It still speaks, handshakes and more. 
>  
>

I don't know about you but I'm not about to leave a spectrum analyzer 
180' up a tower for any period of time.

>Just setting up big shots and blowing people out is bad business for
>everyone. 
>
I am not saying to blow people out of the water with power. I am saying 
to make sure you have ample power and gain to supply a solid signal. 
Running at -78 on a link is not a solid signal in my mind.  We only use 
equipment where we can control the power. We don't run full bore unlike 
alot of WISP operators. We don't plug radios like Motorola Canopy units 
into omni's. And my opinion is if I blow that guy off the air, so be 
it.  It was not properly engineered to begin with. It was finacially 
engineered to get by cheap.



>If the customer wants a quality shot then there should be no
>problem doing a spectrum analysis, freq decision and installation shortly
>after.  
>  
>

But the point is moot if Johnny O comes along on your channel tomorrow 
and blows you off the air (I am only using him as an example).  Then the 
customer is all pissy because he spent money for spectrum analysis that 
was totally moot.

>I agree it's only good for a certain amount of time, but if the customer
>wants a reliable shot then due diligence is better than chance luck.  
>  
>

I don't think a properly engineered link is chance luck. We don't just 
pick a channel out of thin air and go with it. Alot of engineering goes 
into it. Spectrum analysis is just not a factor 99.999 percent of the time.

-B-

>Dustin 
>  
>


-- 
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell




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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[robert maier]

I think you hit the nail on the headBob Moldashel <[EMAIL PROTECTED]> wrote:  AUGH!This whole thread..Some have touched on pieces of it but how about this summary..The Redline is a two piece radio. It does not send 5 Ghz up the cable. It sends an IF frequency which is lower and more forgiving as well as power to operate the outdoor unit. The Redline as pointed out does not have a spectrum analyzer (in the versions I have worked with). As such they probably just checked for RSL on any or all channels. This is not a spectrum analysis by any means. The Redline equipment is great equipment but it is not a spectrum analyzer.A spectrum analysis is flawed in almost any case really because it is only good at the time of the testing and along the path of the test. You rea
 lly will
 only see stronger signals with an omni. But you can still have your signal killed if someone is using directional antennas and looking down your path. There is a big difference from 8 dB to 29 dB.The other case is a 5 Ghz. system in place that only is used at the end of the day or does "dumps' at certain times. Unlike a full duplex radio like a Proxim Tsunami that is talking all the time regardless of the received signal, you may only see a signal when the associated equipment is passing data. In my book you can't do "reliable spectrum analysis" with any radio or assocaited radio card. Yes, there are systems out there that work really well but I would not be willing to bet my reputation on most. Will they get you by in most cases??? Sure. But...To answer your question..Yes, the spectrum analysis was flawed.Personally...we never do spectrum analysis.
  It
 causes more headaches than what it is worth IMHO. Is it great for finding interference?? Sure.I have installed links in lower Manhattan (nearly 70 to date on unlicensed 5 Ghz), Washington DC and Boston without ever needing a spectrum analysis. All these locations are RF hotbeds.A few things to consider. Use a radio with a very good C/I value. Use 2' or larger antennas to keep the beamwidth tight. Use radios that are capable of 5 or 10 Mhz. channels. Use radios with high RF power output. If you need to run transmission line to the radio, use the right stuff for the job. LMR400 and 5 Ghz. are not my considered options unless the cable length is less than 24". We use LMR600 up to 100' and 5/8" heliax after that. make sure the radio has a good receiver threshold. Wherever possible we use 5.3 Ghz.Last and not least consider your neighbors. If there is only one tall building in town and everyone is on it use 5 Ghz
 . you
 are probably in for some challenges. But if you do a spectrum analysis, find a clear channel, build on it and then smile and walk away only to have one of the existing operators change channels and rain on your parade.Its a game of chance but with the proper engineering you can move the odds more in your favor.Good Luck!-B--- Bob MoldashelLakeland Communications, Inc.Broadband Deployment Group1350 Lincoln AvenueHolbrook, New York 11741 USA800-479-9195 Toll Free US & Canada631-585-5558 Fax516-551-1131 Cell-- WISPA Wireless List: wireless@wispa.orgSubscribe/Unsubscribe:http://lists.wispa.org/mailman/listinfo/wirelessArchives: http://lists.wispa.org/pipermail/wireless/
	
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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Bob Moldashel]

Dustin Jurman wrote:


If the spectrum analyzer is left in place for a period of time and setup
with "peak hold" you will quickly find that radio that is used at the end of
the day. It still speaks, handshakes and more. 
 



I don't know about you but I'm not about to leave a spectrum analyzer 
180' up a tower for any period of time.



Just setting up big shots and blowing people out is bad business for
everyone. 

I am not saying to blow people out of the water with power. I am saying 
to make sure you have ample power and gain to supply a solid signal. 
Running at -78 on a link is not a solid signal in my mind.  We only use 
equipment where we can control the power. We don't run full bore unlike 
alot of WISP operators. We don't plug radios like Motorola Canopy units 
into omni's. And my opinion is if I blow that guy off the air, so be 
it.  It was not properly engineered to begin with. It was finacially 
engineered to get by cheap.





If the customer wants a quality shot then there should be no
problem doing a spectrum analysis, freq decision and installation shortly
after.  
 



But the point is moot if Johnny O comes along on your channel tomorrow 
and blows you off the air (I am only using him as an example).  Then the 
customer is all pissy because he spent money for spectrum analysis that 
was totally moot.



I agree it's only good for a certain amount of time, but if the customer
wants a reliable shot then due diligence is better than chance luck.  
 



I don't think a properly engineered link is chance luck. We don't just 
pick a channel out of thin air and go with it. Alot of engineering goes 
into it. Spectrum analysis is just not a factor 99.999 percent of the time.


-B-

Dustin 
 




--
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Dustin Jurman]

If the spectrum analyzer is left in place for a period of time and setup
with "peak hold" you will quickly find that radio that is used at the end of
the day. It still speaks, handshakes and more. 

Just setting up big shots and blowing people out is bad business for
everyone. If the customer wants a quality shot then there should be no
problem doing a spectrum analysis, freq decision and installation shortly
after.  

I agree it's only good for a certain amount of time, but if the customer
wants a reliable shot then due diligence is better than chance luck.  

Dustin 

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Bob Moldashel
Sent: Friday, February 10, 2006 9:49 AM
To: WISPA General List
Subject: Re: [WISPA] Flawed Spectrum Analysis (I think!)

AUGH!


This whole thread..

Some have touched on pieces of it but how about this summary..

The Redline is a two piece radio.  It does not send 5 Ghz up the cable. 
It sends an IF frequency which is lower and more forgiving as well as 
power to operate the outdoor unit. The Redline as pointed out does not 
have a spectrum analyzer (in the versions I have worked with).  As such 
they probably just checked for RSL on any or all channels.  This is not 
a spectrum analysis by any means. The Redline equipment is great 
equipment but it is not a spectrum analyzer.

A spectrum analysis is flawed in almost any case really because it is 
only good at the time of the testing and along the path of the test. You 
really will only see stronger signals with an omni. But you can still 
have your signal killed if someone is using directional antennas and 
looking down your path. There is a big difference from 8 dB to 29 dB.

The other case is a 5 Ghz. system in place that only is used at the end 
of the day or does "dumps' at certain times.  Unlike a full duplex radio 
like a Proxim Tsunami that is talking all the time regardless of the 
received signal, you may only see a signal when the associated equipment 
is passing data. 

In my book you can't do "reliable spectrum analysis" with any radio or 
assocaited radio card. Yes, there are systems out there that work really 
well but I would not be willing to bet my reputation on most.  Will they 
get you by in most cases???  Sure.  
But...

To answer your question..Yes, the spectrum analysis was flawed.

Personally...we never do spectrum analysis.  It causes more headaches 
than what it is worth IMHO.  Is it great for finding interference??  Sure.

I have installed links in lower Manhattan (nearly 70 to date on 
unlicensed 5 Ghz), Washington DC and Boston without ever needing a 
spectrum analysis. All these locations are RF hotbeds.

A few things to consider. Use a radio with a very good C/I value. Use 2' 
or larger antennas to keep the beamwidth tight. Use radios that are 
capable of 5 or 10 Mhz. channels.  Use radios with high RF power output. 
If you need to run transmission line to the radio, use the right stuff 
for the job. LMR400 and 5 Ghz. are not my considered options unless the 
cable length is less than 24".  We use LMR600 up to 100' and 5/8" heliax 
after that. make sure the radio has a good receiver threshold. Wherever 
possible we use 5.3 Ghz.

Last and not least consider your neighbors. If there is only one tall 
building in town and everyone is on it use 5 Ghz. you are probably in 
for some challenges. But if you do a spectrum analysis, find a clear 
channel, build on it and then smile and walk away only to have one of 
the existing operators change channels and rain on your parade.

Its a game of chance but with the proper engineering you can move the 
odds more in your favor.

Good Luck!

-B-


-- 
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Bob Moldashel]

AUGH!


This whole thread..

Some have touched on pieces of it but how about this summary..

The Redline is a two piece radio.  It does not send 5 Ghz up the cable. 
It sends an IF frequency which is lower and more forgiving as well as 
power to operate the outdoor unit. The Redline as pointed out does not 
have a spectrum analyzer (in the versions I have worked with).  As such 
they probably just checked for RSL on any or all channels.  This is not 
a spectrum analysis by any means. The Redline equipment is great 
equipment but it is not a spectrum analyzer.


A spectrum analysis is flawed in almost any case really because it is 
only good at the time of the testing and along the path of the test. You 
really will only see stronger signals with an omni. But you can still 
have your signal killed if someone is using directional antennas and 
looking down your path. There is a big difference from 8 dB to 29 dB.


The other case is a 5 Ghz. system in place that only is used at the end 
of the day or does "dumps' at certain times.  Unlike a full duplex radio 
like a Proxim Tsunami that is talking all the time regardless of the 
received signal, you may only see a signal when the associated equipment 
is passing data. 

In my book you can't do "reliable spectrum analysis" with any radio or 
assocaited radio card. Yes, there are systems out there that work really 
well but I would not be willing to bet my reputation on most.  Will they 
get you by in most cases???  Sure.  
But...


To answer your question..Yes, the spectrum analysis was flawed.

Personally...we never do spectrum analysis.  It causes more headaches 
than what it is worth IMHO.  Is it great for finding interference??  Sure.


I have installed links in lower Manhattan (nearly 70 to date on 
unlicensed 5 Ghz), Washington DC and Boston without ever needing a 
spectrum analysis. All these locations are RF hotbeds.


A few things to consider. Use a radio with a very good C/I value. Use 2' 
or larger antennas to keep the beamwidth tight. Use radios that are 
capable of 5 or 10 Mhz. channels.  Use radios with high RF power output. 
If you need to run transmission line to the radio, use the right stuff 
for the job. LMR400 and 5 Ghz. are not my considered options unless the 
cable length is less than 24".  We use LMR600 up to 100' and 5/8" heliax 
after that. make sure the radio has a good receiver threshold. Wherever 
possible we use 5.3 Ghz.


Last and not least consider your neighbors. If there is only one tall 
building in town and everyone is on it use 5 Ghz. you are probably in 
for some challenges. But if you do a spectrum analysis, find a clear 
channel, build on it and then smile and walk away only to have one of 
the existing operators change channels and rain on your parade.


Its a game of chance but with the proper engineering you can move the 
odds more in your favor.


Good Luck!

-B-


--
Bob Moldashel
Lakeland Communications, Inc.
Broadband Deployment Group
1350 Lincoln Avenue
Holbrook, New York 11741 USA
800-479-9195 Toll Free US & Canada
631-585-5558 Fax
516-551-1131 Cell

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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[JohnnyO]

I think what you thought was RG6 was actually RG59 - Redline is a pretty clean platform so I don't think too many issues will arise from the deployment of that platform in your area.

JohnnyO

On Fri, 2006-02-10 at 07:31 -0600, Cliff Leboeuf wrote:


Thanks for all of the feedback.

 

For clarification, the LMR400 cable was 140 feet and was the only cable that connected the analyzer to the antenna.

 

I am familiar with the IDU and ODU configuration of the Redline equipment.

 

This test was to see what 5.8 RF was present. The customer plans to deploy a series of P2P and P2Mp radios in the same coverage area as two other towers that have 5.8 deployed.

My climber was familiar with the other tower locations, and wanted to ‘prove’ other RF was in the same area, and that the Redline P2Mp has the potential to affect these other towers adversely.



 

Though I have not seen their conclusion, I am not confident in their methods; and the fact that I believe they just want to install. Once they are functional, they are ‘outta here.’ Then, the customer will be left to mitigate any issues that could easily be avoided, or minimized, by using other frequencies. This is a public safety entity and should be using the 4.9Ghz frequency, but I think Redline has this project wrapped up and since they don’t make 4.9Ghz equipment, they are ‘forcing’ the 5.8Ghz and are resisting my ideas tooth and nail.

 

Why create a potential for problems when you know it can be avoided…That the government though! J

 

- Cliff





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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Cliff Leboeuf]

Thanks for all of the feedback.

 

For clarification, the LMR400 cable was 140
feet and was the only cable that connected the analyzer to the antenna.

 

I am familiar with the IDU and ODU
configuration of the Redline equipment.

 

This test was to see what 5.8 RF was
present. The customer plans to deploy a series of P2P and P2Mp radios in the
same coverage area as two other towers that have 5.8 deployed.

My climber was familiar with the other
tower locations, and wanted to ‘prove’ other RF was in the same
area, and that the Redline P2Mp has the potential to affect these other towers adversely.

 

Though I have not seen their conclusion, I
am not confident in their methods; and the fact that I believe they just want
to install. Once they are functional, they are ‘outta here.’ Then,
the customer will be left to mitigate any issues that could easily be avoided,
or minimized, by using other frequencies. This is a public safety entity and
should be using the 4.9Ghz frequency, but I think Redline has this project
wrapped up and since they don’t make 4.9Ghz equipment, they are ‘forcing’
the 5.8Ghz and are resisting my ideas tooth and nail.

 

Why create a potential for problems when
you know it can be avoided…That the government though! J

 

- Cliff








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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Tom DeReggi]




Agreed if that is what they did, send RF straight 
up.. However if the cable going up the tower was a redline cable between indoor 
and outdoor unit, its not straight RF signal going up the tower, it s the 
redline signal between the two compnents. Depends what they were 
doing.
 
Tom DeReggiRapidDSL & Wireless, IncIntAirNet- Fixed Wireless 
Broadband
 
 

  - Original Message - 
  From: 
  Blair Davis 

  To: [EMAIL PROTECTED] ; WISPA General 
  List 
  Sent: Thursday, February 09, 2006 2:32 
  PM
  Subject: Re: [WISPA] Flawed Spectrum 
  Analysis (I think!)
  With 140 ft of LMR-400 at 5.8GHz, the loss is about 15db.  
  With a good antenna topside, you might get some usable results, but not good 
  onesFor the RG6, I can't find any loss specs for freq. above 
  900MHz.  At 900MHz, the loss is about 10db for 140 ft.  
  Extrapolating that to 5.8GHz, I estimate the loss would exceed 30db at 
  5.8GHz!  Not gonna see much of anything!!!If you connect RG-6 
  cable directly to LMR-400 or to N-connector antennas or equipment, you have an 
  impedance mis-match.  I'd expect to loose 6db or more with that mis-match 
  (at each connection!).  This is on top of the cable loss with the 
  RG6.  If they did not use a balun to match the RG6 cable to the N based 
  equipment, then the total loss on the RG6 'test' would exceed 42db!!!  
  Not gonna work.This 'test' was a waste of time.  JohnnyO 
  wrote:
  There was no noise 
detected b/c there was no signal going into the SPEC-AN ! - This sounds like 
something you would do Cliff - sure this guy wasn't related to you ? JohnnyOOn Thu, 2006-02-09 at 10:07 -0600, Cliff 
Leboeuf wrote: 
We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
	a. the analyzer remained in their truck
	b. the antenna from a 5.8Ghz Redline system was hauled about
140'
	c. the original RF cable used was RG6 for 140'(duh?)
	d. the next 140' of RF cable used was LMR400
	e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
	f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna. 

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff



No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.375 / Virus Database: 267.15.3/254 - Release Date: 2/8/2006
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AOL IM Screen Name --  Theory240

West Michigan Wireless ISP
269-686-8648

A division of:
Camp Communication Services, INC

  
  

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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Tom DeReggi]

Redline itself, does not have spectrum analasys capability, from what I 
understood.
Generally Redline user can use it to see if their radio can work well on a 
channel, by looking for loss, and what channel worksbest. but the fact that 
the Redline smashes through 5.8G fine does not mean that others are not 
hammered by it.


Using the Long coax is not that big a deal, as the loss can be factored in. 
However, if using Redline, the coax was probably the cable used to connect 
the indoor and outdoor equipment, which is spec'd to easilly do 150 feet. it 
is not used to carrt the RF signal like a standard radio, the transmitter is 
actually up at the top of the tower with the antenna. The Redline design is 
actually a preferred design because you can get away from CAt5 jacks 
(easilly soiled by weather and electricity), but not have large singal loss 
like with typical COAX carrying the RF signal to antenna.


I think you need to bring connection to "f". They say no interference, and 
you know there is. Therefore that conclusion is false. however maybe you 
should just get better clarification on wether the finding was really, zero 
interference. maybe they meant that some channels are free, so 5.8Ghz will 
be a good option. Its also possible that the polarity used was opposite. Was 
the purpose to test that the Redline would work above noise floor, or to 
determine what the noise floor was in completeness?


Tom DeReggi
RapidDSL & Wireless, Inc
IntAirNet- Fixed Wireless Broadband


- Original Message - 
From: "Cliff Leboeuf" <[EMAIL PROTECTED]>

To: "WISPA General List" 
Sent: Thursday, February 09, 2006 11:07 AM
Subject: [WISPA] Flawed Spectrum Analysis (I think!)


We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
a. the analyzer remained in their truck
b. the antenna from a 5.8Ghz Redline system was hauled about
140'
c. the original RF cable used was RG6 for 140'(duh?)
d. the next 140' of RF cable used was LMR400
e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna.

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff


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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[George]

Another thought is maybe it was alvarion gear or some thing similar that 
 uses a frequency converter at the antenna.

I think they get fed with a small cable.

George
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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Brian Webster]

Cliff,
Are you sure the first 140' was RG6? I think that is 75 ohm cable so 
that
may be a problem, if it was something else it still might have too much loss
at 5.8 GHz to get any signal to the SA. You may be on to something with the
adapters, if they were just using good quality N-Type for all the
connections it should not be a big deal, but if they were going from an N to
BNC or PL259 or any other type of connector not rated for 5.8 GHz that could
introduce big losses. I would have them inquire about the calibration (and
date) of the SA and it's rated sensitivity for 5.8 GHz. Operator skill might
come in to play, if they had too much attenuation switched in to the SA at
the time of the readings it could give the results you state. As far as
seeing your PTP signal, depending on how well you were doing the swing test
and/or the alignment of any nulls on the pattern it is possible that your
link signal would be low enough not to be detected with any of the above
situations. If your link has high gain antennas on both ends the beam width
of your signal could be narrow enough that it might not pass as close to
this tower as you would assume, the best way to check that is to draw a line
on the map between your sites and see if it really does cross this site in
the main beam.



Thank You,
Brian Webster
www.wirelessmapping.com 



-Original Message-
From: Cliff Leboeuf [mailto:[EMAIL PROTECTED]
Sent: Thursday, February 09, 2006 11:07 AM
To: WISPA General List
Subject: [WISPA] Flawed Spectrum Analysis (I think!)


We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
a. the analyzer remained in their truck
b. the antenna from a 5.8Ghz Redline system was hauled about
140'
c. the original RF cable used was RG6 for 140'(duh?)
d. the next 140' of RF cable used was LMR400
e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna.

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff


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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Blair Davis]

With 140 ft of LMR-400 at 5.8GHz, the loss is about 15db.  With a good
antenna topside, you might get some usable results, but not good
ones

For the RG6, I can't find any loss specs for freq. above 900MHz.  At
900MHz, the loss is about 10db for 140 ft.  Extrapolating that to
5.8GHz, I estimate the loss would exceed 30db at 5.8GHz!  Not gonna see
much of anything!!!

If you connect RG-6 cable directly to LMR-400 or to N-connector
antennas or equipment, you have an impedance mis-match.  I'd expect to
loose 6db or more with that mis-match (at each connection!).  This is
on top of the cable loss with the RG6.  If they did not use a balun to
match the RG6 cable to the N based equipment, then the total loss on
the RG6 'test' would exceed 42db!!!  Not gonna work.

This 'test' was a waste of time.

  JohnnyO wrote:

  
  
There was no noise detected b/c there was no signal going into the
SPEC-AN ! - This sounds like something you would do Cliff - sure this
guy wasn't related to you ? 
  
JohnnyO
  
On Thu, 2006-02-09 at 10:07 -0600, Cliff Leboeuf wrote:
  
We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
	a. the analyzer remained in their truck
	b. the antenna from a 5.8Ghz Redline system was hauled about
140'
	c. the original RF cable used was RG6 for 140'(duh?)
	d. the next 140' of RF cable used was LMR400
	e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
	f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna. 

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff



  
  

No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.375 / Virus Database: 267.15.3/254 - Release Date: 2/8/2006
  



-- 
Blair Davis

AOL IM Screen Name --  Theory240

West Michigan Wireless ISP
269-686-8648

A division of:
Camp Communication Services, INC



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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Cliff Leboeuf]

I knew that I PAID my dues for a reason….!
:) I wasn’t treated this way before.

I guess I get what I paid for…Is there a
money-back policy?

- Cliff

 









From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf
Of JohnnyO
Sent: Thursday, February 09, 2006
12:49 PM
To: WISPA
 General List
Subject: Re: [WISPA] Flawed
Spectrum Analysis (I think!)



 

There was no noise detected b/c there was no signal going into the
SPEC-AN ! - This sounds like something you would do Cliff - sure this guy
wasn't related to you ? 

JohnnyO

On Thu, 2006-02-09 at 10:07 -0600, Cliff Leboeuf wrote: 

 We proposed a spectrum analysis for a client. This analysis was to beperformed with a hand-held spectrum analyzer at the height that theequipment was to be mounted. Our offer was rejected. However, we were asked to provide the climber for the other party'sanalysis.  Their analysis was performed as follows:1. Using a 'nice' spectrum analyzer    a. the analyzer remained in their truck    b. the antenna from a 5.8Ghz Redline system was hauled about140'    c. the original RF cable used was RG6 for 140'(duh?)    d. the next 140' of RF cable used was LMR400    e. we know that we shoot directly through one of the sitessurveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two otherlocations surveyed    f. all analysis showed no RF interference (go figure!) I'm not an RF engineer, so would someone help me to explain why therewas no 5.8Ghz interference shown at these locations even though I knowthere to be other 5.8Ghz equipment hitting the towers tested. What is the RF cable loss at 140' of using LMR400 as described above?Also factor in about 4 connectors to adapt the RF cable from theanalyzer to the antenna.  Is this a valid analysis, or am I wrong to comment to this customer thatI feel this analysis if flawed? "Ammunition" that anyone is willing to supply would be appreciated aswell as advice for me to keep my mouth shut. :) - Cliff  




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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[JohnnyO]

There was no noise detected b/c there was no signal going into the SPEC-AN ! - This sounds like something you would do Cliff - sure this guy wasn't related to you ? 

JohnnyO

On Thu, 2006-02-09 at 10:07 -0600, Cliff Leboeuf wrote:


We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
	a. the analyzer remained in their truck
	b. the antenna from a 5.8Ghz Redline system was hauled about
140'
	c. the original RF cable used was RG6 for 140'(duh?)
	d. the next 140' of RF cable used was LMR400
	e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
	f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna. 

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff






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Re: [WISPA] Flawed Spectrum Analysis (I think!)

[Marlon K. Schafer (509) 982-2181]

www.timesmicrowave.com

Go to the online calculator and figure up the losses on your cable.  Be sure 
to set the freq at 5800 mhz.


I'd not even count the connectors as loss, they are usually in the .1 to .5 
range.  But for a survey adding 1dB of loss per connector is safe.


As I read this they had a total of 250ish feet of coax?  Certainly there's 
gonna be basically no signal on the ground.


Here's what I'd do

Go up there with your tools and take pics of what you see.  Tell them that 
something just didn't feel right about the methodology employed and you 
wanted to check your methods against theirs.  Then show them what you found. 
This way it's non offensive to anyone and you should gain a customer for all 
future work.


Good luck,
Marlon
(509) 982-2181   Equipment sales
(408) 907-6910 (Vonage)Consulting services
42846865 (icq)And I run my own wisp!
64.146.146.12 (net meeting)
www.odessaoffice.com/wireless
www.odessaoffice.com/marlon/cam



- Original Message - 
From: "Cliff Leboeuf" <[EMAIL PROTECTED]>

To: "WISPA General List" 
Sent: Thursday, February 09, 2006 8:07 AM
Subject: [WISPA] Flawed Spectrum Analysis (I think!)


We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
a. the analyzer remained in their truck
b. the antenna from a 5.8Ghz Redline system was hauled about
140'
c. the original RF cable used was RG6 for 140'(duh?)
d. the next 140' of RF cable used was LMR400
e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna.

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff


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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[G.Villarini]

140" are 15 db loss plus 2 for the connectors.. the effective gain on the
antenna would be 11 db ... run your calcs

Gino A. Villarini, 
Aeronet Wireless Broadband Corp.
[EMAIL PROTECTED]
www.aeronetpr.com
787.273.4143


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Cliff Leboeuf
Sent: Thursday, February 09, 2006 12:29 PM
To: WISPA General List
Subject: RE: [WISPA] Flawed Spectrum Analysis (I think!)

Gino,
It was Redline's 2' panel.
- Cliff

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of G.Villarini
Sent: Thursday, February 09, 2006 10:15 AM
To: 'WISPA General List'
Subject: RE: [WISPA] Flawed Spectrum Analysis (I think!)

What redline antenna was used? A sector a panel ?

Gino A. Villarini, 
Aeronet Wireless Broadband Corp.
[EMAIL PROTECTED]
www.aeronetpr.com
787.273.4143


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Cliff Leboeuf
Sent: Thursday, February 09, 2006 12:07 PM
To: WISPA General List
Subject: [WISPA] Flawed Spectrum Analysis (I think!)

We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
a. the analyzer remained in their truck
b. the antenna from a 5.8Ghz Redline system was hauled about
140'
c. the original RF cable used was RG6 for 140'(duh?)
d. the next 140' of RF cable used was LMR400
e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna. 

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff


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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[Cliff Leboeuf]

Gino,
It was Redline's 2' panel.
- Cliff

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of G.Villarini
Sent: Thursday, February 09, 2006 10:15 AM
To: 'WISPA General List'
Subject: RE: [WISPA] Flawed Spectrum Analysis (I think!)

What redline antenna was used? A sector a panel ?

Gino A. Villarini, 
Aeronet Wireless Broadband Corp.
[EMAIL PROTECTED]
www.aeronetpr.com
787.273.4143


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Cliff Leboeuf
Sent: Thursday, February 09, 2006 12:07 PM
To: WISPA General List
Subject: [WISPA] Flawed Spectrum Analysis (I think!)

We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
a. the analyzer remained in their truck
b. the antenna from a 5.8Ghz Redline system was hauled about
140'
c. the original RF cable used was RG6 for 140'(duh?)
d. the next 140' of RF cable used was LMR400
e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna. 

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff


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RE: [WISPA] Flawed Spectrum Analysis (I think!)

[G.Villarini]

What redline antenna was used? A sector a panel ?

Gino A. Villarini, 
Aeronet Wireless Broadband Corp.
[EMAIL PROTECTED]
www.aeronetpr.com
787.273.4143


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Cliff Leboeuf
Sent: Thursday, February 09, 2006 12:07 PM
To: WISPA General List
Subject: [WISPA] Flawed Spectrum Analysis (I think!)

We proposed a spectrum analysis for a client. This analysis was to be
performed with a hand-held spectrum analyzer at the height that the
equipment was to be mounted. Our offer was rejected.

However, we were asked to provide the climber for the other party's
analysis.


Their analysis was performed as follows:
1. Using a 'nice' spectrum analyzer
a. the analyzer remained in their truck
b. the antenna from a 5.8Ghz Redline system was hauled about
140'
c. the original RF cable used was RG6 for 140'(duh?)
d. the next 140' of RF cable used was LMR400
e. we know that we shoot directly through one of the sites
surveyed with 5.8Ghz P2P link, and have 5.8 P2Mp links at two other
locations surveyed
f. all analysis showed no RF interference (go figure!)

I'm not an RF engineer, so would someone help me to explain why there
was no 5.8Ghz interference shown at these locations even though I know
there to be other 5.8Ghz equipment hitting the towers tested.

What is the RF cable loss at 140' of using LMR400 as described above?
Also factor in about 4 connectors to adapt the RF cable from the
analyzer to the antenna. 

Is this a valid analysis, or am I wrong to comment to this customer that
I feel this analysis if flawed?

"Ammunition" that anyone is willing to supply would be appreciated as
well as advice for me to keep my mouth shut. :)

- Cliff


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