EIRP.
That is a 100 kW transmitter and a 10 dB antenna.  
Don’t fly your plane too close to those.  I did it once.  

From: Ty Featherling 
Sent: Tuesday, February 24, 2015 9:23 AM
To: af@afmug.com 
Subject: Re: [AFMUG] 711Mhz carrier?

1mil Watts? Whoa! 

-Ty

On Tue, Feb 24, 2015 at 10:07 AM, Bill Prince <part15...@gmail.com> wrote:

  I read somewhere about lots of intermod issues with the transition to DTV a 
few years back.  Probably more pronounced with the kind of power levels they 
are using on some DTV stations.  I know that at least a couple of DTV stations 
are transmitting at 90 dBm up on Sutro in SF.


bp
<part15sbs{at}gmail{dot}com>

On 2/24/2015 6:24 AM, Chuck McCown wrote:

    The inadvertent diode story has been around for a long time.  I think it 
was much more of a problem when you had two broadcasters at a site where the 
difference between their frequencies was on a 2 way FM repeater input 
frequency.  Every active electronic device on the whole site could do the same 
thing.  Remember how everyone used to obsess about intermod products at tower 
sites.  Doesn’t seem to be much of a problem any more.  Or perhaps it is but we 
are all on cell phones now.  

    From: Bill Prince 
    Sent: Monday, February 23, 2015 5:14 PM
    To: af@afmug.com 
    Subject: Re: [AFMUG] 711Mhz carrier?

    Oh I know.  Our tower manager at Black Mt. goes semi-ballistic when he sees 
anything on the tower that is not HDG or stainless or silicon-bronze.  Then 
tells the story of rusting bolts/nuts/washers turning into diodes in the 
presence of higher-power RF.  I don't know how high the power needs to get, but 
we have seen some interesting side-effects on unshielded cable and other 
unshielded components.


bp
<part15sbs{at}gmail{dot}com>

On 2/23/2015 4:04 PM, Jaime Solorza wrote:

      Noise can come from most unexpected places. CQ rag had a story on spark 
plug caused noise on motorcycle knocking out a satellite system on bank 
building.   Chucks advise is good
      And that would be my first step

      Jaime Solorza

      On Feb 23, 2015 3:08 PM, "Peter Kranz" <pkr...@unwiredltd.com> wrote:

        Had an AT&T contractor show up at one of our datacenter sites today and 
claim that one of our radio systems was emitting a carrier at 711Mhz and he 
pointed at where we have a Dragonwave Compact 18Ghz system and Redline AN-80i 
5Ghz system mounted on the building. 



        711Mhz doesn’t sound like an IF of either of these systems to me, but 
I’ve got tickets in with the equipment manuf. It looks like they are some 3rd 
party AT&T has sweeping buildings downtown. Anyone dealt with these guys 
before? He told me he measured a -87 with his directional antenna 10 feet away 
from the equipment and acted like that was a really big deal, sounds like a 
pretty low level to me honestly. Anyone know what the legal limits for spurious 
emissions are in the 700-800Mhz band?



        Peter Kranz
        Founder/CEO - Unwired Ltd
        www.UnwiredLtd.com
        Desk: 510-868-1614 x100
        Mobile: 510-207-0000
        pkr...@unwiredltd.com







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