HomeMy WebLinkAbout100522 Public Comment for KPTZ radio support________________________________
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To Jefferson County Commissioners:
I know that you have appreciated the Covid virus briefings KPTZ radio has supported since the beginning of the pandemic. You have supported and participated. Now, KPTZ urgently needs
your funding support.
When we experience a natural disaster like or worse than the Covid disaster, I know you will want to turn to KPTZ to help communicate, timely, accurate, unfiltered, information to the
local population.
You may not realize that changes in FCC regulations have negatively impacted local towers and disaster backup possibilities for the radio station. The station is requesting not only
your time in participation but now an approval for funding to help keep the station resilient. I urge you to fully fund that request and even consider adding to it.
I am attaching parts of a conversation with Bill Putney who has the technical knowledge that most of us don’t understand. You may or may not know but I earned my PhD in disaster communications,
and it is why I have been a volunteer supporter of KPTZ from the very beginning and why I understand the seriousness of the station’s need.
From Bill Putney:
“What we had before the FCC removed the allocation was a single antenna at Maynard point with an antenna that had a 120-degree beam width. That antenna was about 6” x 4’ (2 square ft).
In our case that antenna took in all the area from about highway 104 to the tip of the Quimper peninsula. That’s the most populated area in Jefferson County and the most potential
interferers. We didn’t have interference because we were the sole licensee to that spectrum and anyone else who wanted to use that spectrum would have had to come to us to work out
a solution for that co-use. That scheme only requires us to add one antenna and radio at each station and no change or additional cost at Maynard peak.
The new design uses Morgan Hill as a hub. The links are all point to point, but there is no additional ongoing cost per additional antenna. Also, the links are all much shorter. That
will allow us to use new much higher frequencies (an order of magnitude higher than current popular Wi-Fi frequencies) because we can tolerate the atmospheric losses over a short link
at higher frequencies. An antenna of about 10” diameter can achieve beam widths of 1.5 degrees. These frequencies are also lightly used and not in common use in home Wi-Fi. So, all
the new links will be in the 24 GHz and 60 GHz bands.
All this is my attempt to explain that there are a lot of things spinning around that we must deal with to reestablish this simple little network.
Wi-Fi [could be] a solution of sorts. If we were to use unlicensed Wi-Fi, we could never be sure that at some critical moment some other person might start up a Wi-Fi on the same channel
we are using. That would either degrade or block our communication.
Directional antennas help, use they limit the possible interfering stations to those that lay on a line described by the beam width of the antennas at both ends. That sets up a paradigm
in which each connection from the hub site to a connected point requires a pair of radios. If we keep Maynard Peak as the hub, there would be 6 times more antennas and radios there
as we have now. BLM gets a fee per antenna. That cost starts to be an incredibly significant ongoing expense. But we could implement that sort of network. If we wanted to significantly
narrow the possible number of interferers, we need to narrow the antenna beam width. On a long link (~10 miles from Maynard Pk to most of the points in our network) with rain additional
link signal loss use of a lower frequency is better because the signal loss is lower than for higher frequencies. If you use a lower frequency to overcome this problem, the antenna
size to achieve the desired narrow beam width is very big. Typical narrow beam width antennas used in commercial microwave systems at Wi-Fi frequencies are 6’-10’ in diameter (30-80
sq ft). The [currently used] KROH tower could not mechanically support that many of that size antenna.
Bill Putney - WB6RFW
Chief Engineer – KPTZ”
Respectfully Submitted,
Rita Marie Kepner, Ph.D.
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