Right. EIRP. Should have clarified.
I do remember flying near one of the phased array radar installations
(part of the DEW line, I think) somewhere between Anchorage and
Fairbanks way back in 1991. As I approached the radar I started hearing
a "whoop whoop whoop" in my intercom. There was some sort of RF warning
on the sectional, so I decided to turn off my radios. But I still heard
the whoop sound. Hmmm. I then turned off the intercom, and the whoop
sound went away. Wow. At that point I turned off everything until I got
several miles down range.
I don't know if those radars are still in operation or not.
bp
<part15sbs{at}gmail{dot}com>
On 2/24/2015 8:25 AM, Chuck McCown wrote:
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 <mailto:[email protected]>
*Sent:* Tuesday, February 24, 2015 9:23 AM
*To:* [email protected] <mailto:[email protected]>
*Subject:* Re: [AFMUG] 711Mhz carrier?
1mil Watts? Whoa!
-Ty
On Tue, Feb 24, 2015 at 10:07 AM, Bill Prince <[email protected]
<mailto:[email protected]>> 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 <mailto:[email protected]>
*Sent:* Monday, February 23, 2015 5:14 PM
*To:* [email protected] <mailto:[email protected]>
*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" <[email protected]
<mailto:[email protected]>> 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 3^rd 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 <http://www.unwiredltd.com/>
Desk: 510-868-1614 x100 <tel:510-868-1614%20x100>
Mobile: 510-207-0000 <tel:510-207-0000>
[email protected] <mailto:[email protected]>
