Hello All,
We have a situation in our house. Two years ago our cable system went
Chapter 7. So we signed up with an ISP that provides a wireless Internet
connection. Radio and antenna are 40 feet up in the big tree out front
of the house and operates at 915 MHz. The radio is connected to our
router (in the basement wiring cabinet) via shielded CAT-5. The house is
wired with CAT-5 in every room and all terminate at the wiring cabinet.
The external power supply feeding power to the radio (POE) is located in
the basement wiring cabinet right next to the routers EPS.
We regularly have Internet problems, losing connection, extremely slow
transfer rates, etc. It seems particularly bad between 6 and 10 pm
(usually a few hours in that block of time). It is pretty consistent
(almost daily). Our ISP pings every radio in the system every 15 seconds
and plots the return time. Normally we run in the 10 to 20 msec range.
But when it goes bad, ping times can exceed 3-5 SECONDS! Or sometimes it
just cannot talk at all. Our radio power levels are always quite strong
(-59 to -63 dBm), even when we cannot ping or pass data. The ISP
compares my return response to another radio less than a mile away from
me. Theirs is always rock steady, nary a ping over 30 msec. He showed me
plots of both radio power levels and ping response times and it is very
clear to me that my system is falling down a lot, to the point of not
even being able to use it.
The router is only a year old, the laptop is only 3 months old. We had
these same problems with the old router and the old desktop too. The
mains wiring is all less than 10 years old and mechanically screwed down
rather than stripped and poked into the outlet, etc. I even went around
to check connections and tightened some loose screws in the old part of
the house two years ago. When I wired the house, I took extra care to
keep good routing and separation of AC, CAT-5, and RF. All network and
RF connectors are good quality and poor crimp connections were not
tolerated. Everything is tight and in good order.
The ISP says it is not the radio, but somehow the data is getting hosed
before it can be modulated onto the carrier. He thinks it is something
in my house causing the problem. He said he has seen problems before
with wireless telephones, Blackberry's, motion detectors, and some other
things. We do have a 900 MHz wireless telephone that is 5-7 years old.
After my most recent conversation with the ISP, I decided to disconnect
the 900 MHz wireless phone. I had not told the ISP and tonight he
emailed me and asked what we had done. He said the system graphs had
improved dramatically. Next week we are going to plug the phone back in
and see if the problem repeats.
My question(s) to the list are how do you explain this? Is it radiated
as in two radios beating against each other or your more normal radiated
EMI getting in the system hardware? Is it conducted on the mains or the
network wiring? Where is the ingress occurring? Can the phone make
enough EMI to trash the data getting into the radio? I will also be
looking for a solution (besides trashing the phone).
I have my ideas and opinions but will hold those for now. As always, I
will be looking forward to the interesting comments, ideas, and
solutions that come from you all.
Thanks in advance for your replies.
Best,
Scott
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