parabolic reflector for WiFi

N

Norm X

Hi,

I'm interested in any feedback I can get regarding use of a parabolic
reflector for distance reception of WiFi, in the 2.5 GHz band. Encryption is
not a problem for me, nor the NSA. I am adverse to spending any money.

https://www.google.ca/search?q=para...v&sa=X&ei=5LXcUvDRKsrFoASWo4DoCw&ved=0CCwQsAQ

shows a number of ideas. One idea appears to use a wire mesh colander, which
I could pick up used, at a thrift store. Or a tin can. Comments?

At one time I was interested in DIY projects for UHF. In Canada, terrestrial
HD television is carried at 470-806 MHz. However, I abandoned DIY and was
lucky to find a 15 dB gain directional, polarized UHF antenna from Israel
for $20 and $12 postage. My model is better than this one here:

http://www.cuscus.us/upload/Ebay/MCM/30-2071.jpg

I also use a 15dB gallium arsenide cable amp. My rig is highly directional
and picks up all the signals from one broadcast tower on the other side of
the Salish Sea. However, it is a painfully tedious to point to US broadcast
towers.

High directional gain would not be a problem with 2.5 GHz WiFi. 2.5 GHz RF
is reflected easily off clouds and some surfaces and would lose any
polarization. Comments?

One can buy some really good hardware for the price that is charged by
service providers.

X
 
P

philo 

Hi,

I'm interested in any feedback I can get regarding use of a parabolic
reflector for distance reception of WiFi, in the 2.5 GHz band. Encryption is
not a problem for me, nor the NSA. I am adverse to spending any money.

https://www.google.ca/search?q=para...v&sa=X&ei=5LXcUvDRKsrFoASWo4DoCw&ved=0CCwQsAQ

shows a number of ideas. One idea appears to use a wire mesh colander, which
I could pick up used, at a thrift store. Or a tin can. Comments?

At one time I was interested in DIY projects for UHF. In Canada, terrestrial
HD television is carried at 470-806 MHz. However, I abandoned DIY and was
lucky to find a 15 dB gain directional, polarized UHF antenna from Israel
for $20 and $12 postage. My model is better than this one here:

http://www.cuscus.us/upload/Ebay/MCM/30-2071.jpg

I also use a 15dB gallium arsenide cable amp. My rig is highly directional
and picks up all the signals from one broadcast tower on the other side of
the Salish Sea. However, it is a painfully tedious to point to US broadcast
towers.

High directional gain would not be a problem with 2.5 GHz WiFi. 2.5 GHz RF
is reflected easily off clouds and some surfaces and would lose any
polarization. Comments?

One can buy some really good hardware for the price that is charged by
service providers.

X
Click to expand...




http://www.freeantennas.com/projects/template2/
 
J

John McGaw

Hi,

I'm interested in any feedback I can get regarding use of a parabolic
reflector for distance reception of WiFi, in the 2.5 GHz band. Encryption is
not a problem for me, nor the NSA. I am adverse to spending any money.

https://www.google.ca/search?q=para...v&sa=X&ei=5LXcUvDRKsrFoASWo4DoCw&ved=0CCwQsAQ

shows a number of ideas. One idea appears to use a wire mesh colander, which
I could pick up used, at a thrift store. Or a tin can. Comments?

At one time I was interested in DIY projects for UHF. In Canada, terrestrial
HD television is carried at 470-806 MHz. However, I abandoned DIY and was
lucky to find a 15 dB gain directional, polarized UHF antenna from Israel
for $20 and $12 postage. My model is better than this one here:

http://www.cuscus.us/upload/Ebay/MCM/30-2071.jpg

I also use a 15dB gallium arsenide cable amp. My rig is highly directional
and picks up all the signals from one broadcast tower on the other side of
the Salish Sea. However, it is a painfully tedious to point to US broadcast
towers.

High directional gain would not be a problem with 2.5 GHz WiFi. 2.5 GHz RF
is reflected easily off clouds and some surfaces and would lose any
polarization. Comments?

One can buy some really good hardware for the price that is charged by
service providers.

X
Click to expand...
If you are not irrevocably wedded to the idea of DIY then there are any
number of easy and relatively inexpensive off-the-shelf solutions with up
to 24dbi gain that should give great signals over several kilometers. The
big thing is to have a router and antenna which have compatible connectors
or really good adapters since so many commercial antennas seem to have 'N'
connectors and thick coax (to minimize losses).
 
N

Norm X

If you are not irrevocably wedded to the idea of DIY then there are any
number of easy and relatively inexpensive off-the-shelf solutions with up
to 24dbi gain that should give great signals over several kilometers. The
big thing is to have a router and antenna which have compatible connectors
or really good adapters since so many commercial antennas seem to have 'N'
connectors and thick coax (to minimize losses).
Click to expand...

Goodness. I don't want to encourage anyone to bid against me, but I see a
number of directional WiFi antennae from China for just over $1 on eBay.
Population density dictates that Chinese hackers are more highly evolved
than we.
 
N

Norm X

"philo " wrote
http://www.freeantennas.com/projects/template2/
Click to expand...

Thanks. I got some plastic from a local supplier.

This is a good place to report improvements in WiFi signal quality that can
be had by using a powered USB hub. I have a dual band USB WiFi adapter
hanging from a hook on the apartment balcony rafters. I had three lengths of
USB cable daisy chained. Then I started to worry about USB cable length.
Google research says to use a USB hub to stretch USB cable reach. Maybe up
to five USB hubs can be used in series as repeaters to extend reach to 50
meters. When I replaced one length of USB cable with a USB hub I got a very
good improvement in WiFi Internet signal quality and speed. All this is done
with parts from recycled e-waste.

Indoors I have an Ethernet switch to connect five computers. A $20 Ethernet
switch is a big improvement from an Ethernet hub that can be had by
configuring a cheap router.

There is far too much RF noise at 2.5 GHz. This frequency is a (small)
contributor to the risk of cancer.


X
 
P

Paul

Norm said:
"philo " wrote


Thanks. I got some plastic from a local supplier.

This is a good place to report improvements in WiFi signal quality that can
be had by using a powered USB hub. I have a dual band USB WiFi adapter
hanging from a hook on the apartment balcony rafters. I had three lengths of
USB cable daisy chained. Then I started to worry about USB cable length.
Google research says to use a USB hub to stretch USB cable reach. Maybe up
to five USB hubs can be used in series as repeaters to extend reach to 50
meters. When I replaced one length of USB cable with a USB hub I got a very
good improvement in WiFi Internet signal quality and speed. All this is done
with parts from recycled e-waste.

Indoors I have an Ethernet switch to connect five computers. A $20 Ethernet
switch is a big improvement from an Ethernet hub that can be had by
configuring a cheap router.

There is far too much RF noise at 2.5 GHz. This frequency is a (small)
contributor to the risk of cancer.


X
Click to expand...

Who needs WiFi radiation, when you can get a radio signal
off USB3 cables. I found this yesterday.

http://www.intel.com/content/dam/ww...-papers/usb3-frequency-interference-paper.pdf

Paul
 
N

Norm X

"philo " wrote

http://www.freeantennas.com/projects/template2/

Thanks again for the project schematics. I constructed the project using PVC
film, scotch tape and tin foil, mounted it outside and directed it in the
general direction of a target AP. Now I have a connection to the Internet of
about equal quality to that of wired Ethernet. My Xbox 360 is very happy.

X
 
P

Paul

Norm said:
"Paul" wrote


Paul, do you think ferrite will help? A lot of USB 2.0 cables have built in
ferrite chokes. My Sony HDTV came with a lot of ferrite chokes. I have
become somewhat religious about wrap around ferrite chokes. Is my faith
misplaced?
Click to expand...

There's no question ferrite works. I used to use it in
my designs, for electrical filter circuits. It's a
resistive dissipater at high frequencies. You have
to select a ferrite type, for the frequency of interest.
Then the question would be, do they make a ferrite
composition for 2.5GHz. Going from memory, the highest
I might have seen, is one peaking at 1GHz.

What's peculiar, is finding that document on the Intel
site, of all places. You'd think I'd be finding it
on usb.org :)

I don't see a reason why Intel Thunderbolt would not be
as bad. If that was the intention of putting the document
on the Intel site (Intel promoting Thunderbolt over USB3).

I'd rather the people who did that series of experiments,
put a ferrite on the USB3 cable and retest. Rather than
us doing it out here, with no equipment to use. There must
be a reason that ferrite wasn't applied in that report. My
RF guy at work, who purchased the gear for emissions work,
also purchased ferrite kits (probably a thousand dollars worth),
so those guys know all about it. It's not a secret or anything.

Paul


Paul
 
N

Norm X

I discovered a new source of WiFi interference, broadband RF from
fluorescent lighting ballast. I was surprised at the change in WiFi speed
when I turned off my fluorescent lights. My WiFi parabolic reflector is
directed _away_ from my apartment. Further research revealed that the
mechanism of interference is through unshielded USB cabling.

Internally I have an Ethernet switch and a network of five computers. For
peak performance I need to not only graduate to shielded USB but also from
unshielded Cat 5e to shielded Cat 6 Ethernet cabling. With all the money I
save not paying ISP costs, this is attainable.

"Norm X" wrote in message
"philo " wrote

http://www.freeantennas.com/projects/template2/

Thanks again for the project schematics. I constructed the project using PVC
film, scotch tape and tin foil, mounted it outside and directed it in the
general direction of a target AP. Now I have a connection to the Internet of
about equal quality to that of wired Ethernet. My Xbox 360 is very happy.

X
 
N

Norm X

I discovered a new source of WiFi interference, broadband RF from
fluorescent lighting ballast. I was surprised at the change in WiFi speed
when I turned off my fluorescent lights. My WiFi parabolic reflector is
directed _away_ from my apartment. Further research revealed that the
mechanism of interference is through unshielded USB cabling.

Internally I have an Ethernet switch and a network of five computers. For
peak performance I need to not only graduate to shielded USB but also from
unshielded Cat 5e to shielded Cat 6 Ethernet cabling. With all the money I
save not paying ISP costs, this is attainable.

"Paul" wrote in message
Norm said:
"Paul" wrote


Paul, do you think ferrite will help? A lot of USB 2.0 cables have built
in ferrite chokes. My Sony HDTV came with a lot of ferrite chokes. I have
become somewhat religious about wrap around ferrite chokes. Is my faith
misplaced?
Click to expand...

There's no question ferrite works. I used to use it in
my designs, for electrical filter circuits. It's a
resistive dissipater at high frequencies. You have
to select a ferrite type, for the frequency of interest.
Then the question would be, do they make a ferrite
composition for 2.5GHz. Going from memory, the highest
I might have seen, is one peaking at 1GHz.

What's peculiar, is finding that document on the Intel
site, of all places. You'd think I'd be finding it
on usb.org :)

I don't see a reason why Intel Thunderbolt would not be
as bad. If that was the intention of putting the document
on the Intel site (Intel promoting Thunderbolt over USB3).

I'd rather the people who did that series of experiments,
put a ferrite on the USB3 cable and retest. Rather than
us doing it out here, with no equipment to use. There must
be a reason that ferrite wasn't applied in that report. My
RF guy at work, who purchased the gear for emissions work,
also purchased ferrite kits (probably a thousand dollars worth),
so those guys know all about it. It's not a secret or anything.

Paul


Paul
 
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