Just info I've gleamed from talking to these guys. I think they can
only support 3 or 4 customers per frequency, one tower we're on has 3
separate antennas, so they can support more customers. They refer to
their data transfer as 'chirping data' One of the operators says that
they have to listen to see if a channel is available before starting
transmitting. They're usually using some sort of motor drive antenna to
push the elements in/out to change the antenna frequency.
We provide OOB Management to one operator who goes Chicago <-> Israel.
Another one of them causing us the interference is Chicago<-> Germany.
And the 3rd we've worked with with is Chicago<->Seattle.
There are about 10 other sites that I've found so far scattered within
15 miles of us, all doing this same thing. 6/11/18ghz microwave back to
the tower at the CME datacenter, then Shortwave transmission to
wherever. And these guys all pretend that what they're doing is super
secret. I've heard that the tower at the Datacenter actually has to
make sure the data lines to every radio are equal length, regardless of
where it's at on the tower, so everyone is timed equally.
On 12/19/2020 11:36 AM, Brian Webster wrote:
With some of the DSP methods on amateur radio today using sound cards, you
would be surprised how much fade you can take and still decode data. Modes such
as PSK31, FT8 and others can still decode when you cannot actually hear the
signal from the speaker. They are very spectrally efficient compared to even
SSB voice. As Chuck mentioned if you are sending low bandwidth data it's a
viable option.
Thank you,
Brian Webster
-----Original Message-----
From: AF [mailto:[email protected]] On Behalf Of Chuck McCown via AF
Sent: Saturday, December 19, 2020 11:45 AM
To: Matt Hoppes
Cc: [email protected]; AnimalFarm Microwave Users Group
Subject: Re: [AFMUG] High-Frequency Traders Push Closer to Light Speed With
Cutting-Edge Cables - WSJ
Multi freq diversity, they may be even using some kind of noise modulation
with a fiber backup.
High power CW can almost always hammer through on some freq.
Red cross has a handful of channels that almost always seem to work.
-----Original Message-----
From: Matt Hoppes
Sent: Saturday, December 19, 2020 9:41 AM
To: [email protected]
Cc: AnimalFarm Microwave Users Group
Subject: Re: [AFMUG] High-Frequency Traders Push Closer to Light Speed With
Cutting-Edge Cables - WSJ
I get that. It’s all good until you’ve got a million dollars tied up in a
buy deal you want to dump and you get fade.
On Dec 19, 2020, at 11:39 AM, [email protected] wrote:
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