Family complaining about poor internet wireless reception around the castle.
A quick search and I see the first thing to try before boosters and
repeaters is simply a bigger aerial on the router (currently 3" long) at a
cost of around £20. Being a tight wad I thought I might test a home made
aerial first - an aerial is just a length of metal I think - and am
considering how to do it.

Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something? I am guessing the aerial can be
thin - a coat hanger not necessary here - but is solid copper better than
strands?

Tim W

On Mon, 13 Jun 2011 08:26:40 +0100, Tim W wrote:

Am I right in thinking I can leave the insulation on a length of copper
wire and use that?

Yes.

Will the length I cut it at make a difference?

Yes, critical.

I mean obviously it will be longer, maybe 30" instead of 3" but does it
have to be a multiple of a wavelength or something?

Yes, but it's not quite that simple.

Connecting it to the router with low enough loss coax and the small
connectors will be the tricky bit. Far less bother to move the
wireless AP to a better location. What it's built into the same box
as the ADSL modem and that can't be moved easily. Bit stupid rarerly
is the best place for the ADSL modem the best place for a wireless
AP.

The wireless AP needs to be located away from things as much as
possible, stuffed down the back of a desk surrounded by monitors and
PC's is not, erm, ideal. You can buy aerials and TBH that is probably
the better choice as it should come with suitable cable and
connectors etc.

--
Cheers
Dave.

Tim W wrote:

an aerial is just a length of metal I think

Sometimes with embedded voodo, the ones embedded within laptop screens
especially so.

Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something?

Usually 1/4 or 1/2 wavelength, but that'll be what you already have

http://www.fpvuk.org/forum/index.php?topic=1391.0

I am guessing the aerial can be
thin - a coat hanger not necessary here - but is solid copper better than
strands?

What's the velocity factor of a coathanger?

If you want to make existing access point more directional, you could
try this

http://www.freeantennas.com/projects/Ez-10/

On Jun 13, 8:48*am, Andy Burns wrote:
Tim W wrote:
an aerial is just a length of metal I think

Sometimes with embedded voodo, the ones embedded within laptop screens
especially so.

Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something?

Usually 1/4 or 1/2 wavelength, but that'll be what you already have

http://www.fpvuk.org/forum/index.php?topic=1391.0

I am guessing the aerial can be
thin - a coat hanger not necessary here - but is solid copper better than
strands?

What's the velocity factor of a coathanger?

If you want to make existing access point more directional, you could
try this

http://www.freeantennas.com/projects/Ez-10/

I get similar moans from my son whose pc is at the other end of the
house and having been in electronics, though not RF, can at least do
all the making part.

I read through the links and was rewarded at least in understanding
why a coat hanger might have a velocity factor :) - no doubt this
factor was mentioned in my training all too many years ago now.

Two questions - why does the designer of the aerial on the FPV forum
not take the velocity factor into account, and why does it only apply
to the 'folded' back section - I can't see that the 'bazooka'
configuration is any different electrically?

Rob

On Mon, 13 Jun 2011 08:26:40 +0100, "Tim W"
wrote:


Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something? I am guessing the aerial can be
thin - a coat hanger not necessary here

?? Thin implies sharply tuned. It's unlikely to be anything like
right.

For a Yagi type beam think in terms of elements at least the diameter
of a pencil. Microbore copper tubing would spring to mind.

I do possess a comercially made beam. If anybody wants the dimensions
email me.

Derek G.

- but is solid copper better than
strands?

Tim W

On Mon, 13 Jun 2011 08:26:40 +0100, Tim W wrote:

Family complaining about poor internet wireless reception around the
castle. A quick search and I see the first thing to try before boosters
and repeaters is simply a bigger aerial on the router (currently 3"
long) at a cost of around £20. Being a tight wad I thought I might test
a home made aerial first - an aerial is just a length of metal I think -
and am considering how to do it.

Am I right in thinking I can leave the insulation on a length of copper
wire and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to
be a multiple of a wavelength or something? I am guessing the aerial can
be thin - a coat hanger not necessary here - but is solid copper better
than strands?



A bigger aerial doesn't help on a transmitter, only on a receiver. That
makes it useless on a wireless router. The electrical length of the
aerial is fairly critical to it's performance (and isn't usually the same
as the mechanical length!). Also, many router aerials are actually a
solid or flexible core with the aerial wire wound around it. The whole
thing is then covered with insulation. If you want to try a mod then go
ahead, but I doubt very much if it will make things better - probably
much worse so make sure that your mod is easily reversible! As the
original is almost certainly tuned to 1/4 wavelength you could try
something exactly twice the length to make it 1/2 wave or even work out a
length for 5/8 wavelength (which is probably better than either but not
legal as it has gain).

The very best way to get more range is to move the unit to a central
location in the house. If that doesn't work very well for keeping the ADSL
lead short then you could add a separate non-wireless ADSL router and
connect it to the wireless one using CAT5, effectively putting them on
their own wired network.

--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info
Filtering everything posted from googlegroups to kill spam.

In article , Andy
Burns scribeth thus
Tim W wrote:

an aerial is just a length of metal I think

Sometimes with embedded voodo, the ones embedded within laptop screens
especially so.

Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something?

Usually 1/4 or 1/2 wavelength, but that'll be what you already have

http://www.fpvuk.org/forum/index.php?topic=1391.0

I am guessing the aerial can be
thin - a coat hanger not necessary here - but is solid copper better than
strands?

What's the velocity factor of a coathanger?

If you want to make existing access point more directional, you could
try this

http://www.freeantennas.com/projects/Ez-10/

You'd be better off getting another Access point and relaying the one
you have. Unless you want to improve the range of this existing system
in -One- direction i.e. focusing the power you have rather than
broadcasting it then any additional aerial you add onto the existing
ones isn't likely to make it any better..


BTW .. Aeriel is spelt Aerial ;!...
--
Tony Sayer

In article
s.com, robgraham scribeth thus
On Jun 13, 8:48*am, Andy Burns wrote:
Tim W wrote:
an aerial is just a length of metal I think

Sometimes with embedded voodo, the ones embedded within laptop screens
especially so.

Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something?

Usually 1/4 or 1/2 wavelength, but that'll be what you already have

http://www.fpvuk.org/forum/index.php?topic=1391.0

I am guessing the aerial can be
thin - a coat hanger not necessary here - but is solid copper better than
strands?

What's the velocity factor of a coathanger?

If you want to make existing access point more directional, you could
try this

http://www.freeantennas.com/projects/Ez-10/

I get similar moans from my son whose pc is at the other end of the
house and having been in electronics, though not RF, can at least do
all the making part.

I read through the links and was rewarded at least in understanding
why a coat hanger might have a velocity factor :) - no doubt this
factor was mentioned in my training all too many years ago now.

Two questions - why does the designer of the aerial on the FPV forum
not take the velocity factor into account, and why does it only apply
to the 'folded' back section - I can't see that the 'bazooka'
configuration is any different electrically?

Rob


The velocity factor is the slowing of a Radio frequency signal in a
metal as In metals they travel slower than free space...

Its all there on goggle...

--
Tony Sayer

In article , Derek G.
scribeth thus
On Mon, 13 Jun 2011 08:26:40 +0100, "Tim W"
wrote:


Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something? I am guessing the aerial can be
thin - a coat hanger not necessary here

?? Thin implies sharply tuned. It's unlikely to be anything like
right.

Diameter of the radiating elements has a function on bandwidth..


For a Yagi type beam think in terms of elements at least the diameter
of a pencil. Microbore copper tubing would spring to mind.

Useful stuff..


I do possess a comercially made beam. If anybody wants the dimensions
email me.

Derek G.

- but is solid copper better than
strands?

Not in this instance at those frequencies .. conduction is on the
surface of the metal, look up "skin effect"...

Tim W




--
Tony Sayer

On Jun 13, 9:38*am, tony sayer wrote:
In article
s.com, robgraham scribeth thus









On Jun 13, 8:48*am, Andy Burns wrote:
Tim W wrote:
an aerial is just a length of metal I think

Sometimes with embedded voodo, the ones embedded within laptop screens
especially so.

Am I right in thinking I can leave the insulation on a length of copper wire
and use that? Will the length I cut it at make a difference? I mean
obviously it will be longer, maybe 30" instead of 3" but does it have to be
a multiple of a wavelength or something?

Usually 1/4 or 1/2 wavelength, but that'll be what you already have

http://www.fpvuk.org/forum/index.php?topic=1391.0

I am guessing the aerial can be
thin - a coat hanger not necessary here - but is solid copper better than
strands?

What's the velocity factor of a coathanger?

If you want to make existing access point more directional, you could
try this

http://www.freeantennas.com/projects/Ez-10/

I get similar moans from my son whose pc is at the other end of the
house and having been in electronics, though not RF, can at least do
all the making part.

I read through the links and was rewarded at least in understanding
why a coat hanger might have a velocity factor :) - no doubt this
factor was mentioned in my training all too many years ago now.

Two questions - why does the designer of the aerial on the FPV forum
not take the velocity factor into account, and why does it only apply
to the 'folded' back section - I can't see that the 'bazooka'
configuration is any different electrically?

Rob

The velocity factor is the slowing of a Radio frequency signal in a
metal as In metals they travel slower than free space...

Its all there on goggle...

--
Tony Sayer

Yep, Tony - been to Google and read that. Google might answer my
exact questions if I could find the right search terms but then that
doesn't help anyone else. It's the exact questions that require the
answer.

Rob

On 13 Jun 2011 08:32:13 GMT, mick wrote:

A bigger aerial doesn't help on a transmitter, only on a receiver.

Rubbish.

That makes it useless on a wireless router.

A wireless router also recieves how else does it provide a
bidirectional link?

--
Cheers
Dave.

In message on Mon, 13 Jun 2011 09:35:47 +0100
tony sayer wrote:

In article , Andy
Burns scribeth thus

If you want to make existing access point more directional, you could
try this

http://www.freeantennas.com/projects/Ez-10/

You'd be better off getting another Access point and relaying the one
you have. Unless you want to improve the range of this existing system
in -One- direction i.e. focusing the power you have rather than
broadcasting it then any additional aerial you add onto the existing
ones isn't likely to make it any better..


BTW .. Aeriel is spelt Aerial ;!...

If, as Tony says, you can live with a uni-directional aerial - depends, of
course, on the location of all receivers wrt to the transmitter - the corner
director in Andy's link should do the trick and costs virtually nothing.

Forget about velocity factors and coat hangers - anything you come up with will
be worse than you've already got, unless you built a well designed multi
element directional aerial at considerable expense ...

Note the important words the 'well designed' 'directional' 'expense' and
compare with about fourpence for the much better corner reflector with proven
performance ...

Otherwise follow Tony's advice ...

--

Terry

"robgraham" wrote in message
...


Yep, Tony - been to Google and read that. Google might answer my
exact questions if I could find the right search terms but then that
doesn't help anyone else. It's the exact questions that require the
answer.

The velocity factor affects the length required to be a wavelength.
It affects the matching, etc and hence the performance at the required
frequency.
E.g. a quarter wave isn't the same in free air as it is in coax or on a yagi
for the same frequency.

I would move the router about before touching the aerials.
A move of a few inches can make a big difference.

"Tim W" wrote in message
...

Family complaining about poor internet wireless reception around the
castle. .... bigger aerial on the router
....tight wad ....home made ...


Thanks for replies.

We won't mess with the aerial for the minute. We will start with a tinfoil
reflector on the router aerial. Then a colander/seive dish on the usb dongle
thing on the PC upstairs. Kids won't thank me for that, they want technology
that costs money.

Tim w

In message m, mick
writes
A bigger aerial doesn't help on a transmitter, only on a receiver.
Don't transmitters have antennae?
--
hugh
"Believe nothing. No matter where you read it, Or who said it, Even if
I have said it, Unless it agrees with your own reason And your own
common sense." Buddha

The velocity factor is the slowing of a Radio frequency signal in a
metal as In metals they travel slower than free space...

Its all there on goggle...

--
Tony Sayer

Yep, Tony - been to Google and read that. Google might answer my
exact questions if I could find the right search terms but then that
doesn't help anyone else. It's the exact questions that require the
answer.

Rob

So what exactly do you want to know then?...
--
Tony Sayer

hugh wrote:
In message m, mick
writes
A bigger aerial doesn't help on a transmitter, only on a receiver.
Don't transmitters have antennae?

course the do, and that's why they put a couple of inches on Droitwich
instead of the 200 meter tall towers and ground planes they thought they
needed before mick told them they had been wasting their time for 60 years.

"Tim W" wrote in message
...

"Tim W" wrote in message
...

Family complaining about poor internet wireless reception around the
castle. .... bigger aerial on the router
....tight wad ....home made ...


We won't mess with the aerial for the minute. We will start with a tinfoil
reflector on the router aerial. Then a colander/seive dish on the usb
dongle thing on the PC upstairs. Kids won't thank me for that, they want
technology that costs money.

And reporting that they both make a significant difference. Problem
solved.Cost nil

Tim W

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Tim W"
saying something like:

We won't mess with the aerial for the minute. We will start with a tinfoil
reflector on the router aerial. Then a colander/seive dish on the usb
dongle thing on the PC upstairs. Kids won't thank me for that, they want
technology that costs money.

And reporting that they both make a significant difference. Problem
solved.Cost nil

I found that out a few years ago after discovering the New Zealand site.
http://www.usbwifi.orconhosting.net.nz/