[SBE16-Seattle] Alert: C-band experimental license

[Lowell Kiesow]

I got a coordination notice for experimental license WL2XSU (file #
0374-EX-CN-2021). It can potentially interfere with satellite reception by
a number of C-band earth stations, also known as downlinks.  AT&T has a
license to put up 60 test transmitters on 3700-3702 MHz, with an ERP of 61
Watts each, all over western Washington.  Because this is for propagation
testing, they likely will be doing this in some other parts of the United
States.  I do not know where else they are doing it.

This should not be a problem for those earth stations that have the
infamous "blue, 5G filter" installed. (The blue filter is a 4000-4200 MHz
bandpass).  However, since the deadline for putting on filters isn't
until *December
5, 2021*, I assume there are many vulnerable systems right now.  Without a
filter ahead of the LNB, a strong terrestrial signal in that frequency
range can overload the LNB, and cause interference.  The frequency
coordinator for WL2XSU told me they could power up test transmitters right
after the window closes for objections.  The window closes *June 28th*.

The only saving grace is the special condition on the FCC license that
requires immediate shutdown in the event of interference to an earth
station.  Supposedly, the one guy, whose cell phone is listed on the
license and located in Texas, can turn the transmitter off here in Tacoma
very quickly, at any hour of the day.

I am filing an objection to operating WL2XSU prior to 12/5/21.  If you have
a licensed earth station, check your email for a coordination notice from
ExperimentalCoordination at radyne.com
You can file objections to that email address, too.  If the earth station
licensee did not get an email from them, you may not have to worry unless
you are in western Washington.  Stay alert for notices for your area and
get those filters installed!

Lowell Kiesow
Chief Engineer
*88* <http://knkx.org/>*.* <http://www.jazz24.org/>*5 FM KNKX*
<http://knkx.org/> ●*  Jazz24.org <http://www.jazz24.org/>*
lkiesow at knkx.org ●
[image: knkx.org] <http://knkx.org>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sea.sbe16.org/pipermail/sbe16-seattle/attachments/20210727/cc9cd091/attachment.html>