They let you get that close in Class B? Hmmm...
On 02/24/2015 09:00 AM, Chuck McCown wrote:
Probably 300 feet but probably right in the center of the lobe too.
*From:* Ty Featherling <mailto:[email protected]>
*Sent:* Tuesday, February 24, 2015 9:40 AM
*To:* [email protected] <mailto:[email protected]>
*Subject:* Re: [AFMUG] 711Mhz carrier?
Cool. How far from it did you get?
-Ty
On Tue, Feb 24, 2015 at 10:38 AM, Chuck McCown <[email protected]
<mailto:[email protected]>> wrote:
All the aircraft radios noised up and became unusable and I was in
class B airspace at the time flying with a clearance.
*From:* Ty Featherling <mailto:[email protected]>
*Sent:* Tuesday, February 24, 2015 9:28 AM
*To:* [email protected] <mailto:[email protected]>
*Subject:* Re: [AFMUG] 711Mhz carrier?
What happened?
-Ty
On Tue, Feb 24, 2015 at 10:25 AM, Chuck McCown <[email protected]
<mailto:[email protected]>> 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]>
!DSPAM:2,54ecae1d282581898217438!
