Extending wi-fi

On 07/01/2014 07:01, Geoff Pearson wrote:

OK - how do I plug an iPad into an Ethernet socket?

Scrub the post I just sent, if it appeared on your server, wrong product

--
Mark
Please replace invalid and invalid with gmx and net to reply.

Mark Carver wrote:

On 07/01/2014 07:01, Geoff Pearson wrote:

how do I plug an iPad into an Ethernet socket?

With this ?
http://store.apple.com/uk/product/MC...hernet-adapter

Now all you need is a USB OTG socket for an iPad :-P

In article , Ian Jackson
wrote:


Modern one are supposed to notch out the amateur bands - but it's not
all of the bands. And it's only a matter of time before this requirement
starts to be conveniently forgotten in the interests of increasing the
bandwidth. Also, I think there are proposals to increase the transmit
power levels, which will tend to make any notch filtering inadequate.

Also, the domestic mains plus all the equipment attached to it may well
have nonlinearity, thus causing intermod to shift power into any 'gaps'
that work nicely in a test lab. Also to spray some of it into the band
above the range intended.

The whole idea of devices using RF over the mains under the pretense that
they are "not transmitters" is absurd.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Jim Lesurf wrote:


The whole idea of devices using RF over the mains under the pretense that
they are "not transmitters" is absurd.

Agreed. How does regulation of this compare with regulation of cable
companys, who have cabinets that sometimes leak RF?

Bill

In message , Bill Wright
writes
Jim Lesurf wrote:

The whole idea of devices using RF over the mains under the pretense
that
they are "not transmitters" is absurd.

Agreed. How does regulation of this compare with regulation of cable
companys, who have cabinets that sometimes leak RF?

As I'm sure you will know, cable TV systems have to comply with the
quite stringent specs in BS1510 and BS1520 (and/or whatever the latest
EN successors are).
--
Ian

In article , Bill Wright
wrote:
Jim Lesurf wrote:


The whole idea of devices using RF over the mains under the pretense
that they are "not transmitters" is absurd.

Agreed. How does regulation of this compare with regulation of cable
companys, who have cabinets that sometimes leak RF?

No idea about the cable cabinets. But AIUI OfCom simply classify the home
mains RF systems as "not transmitters" and take no real interest beyond
that.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

On Tue, 07 Jan 2014 09:21:37 +0000 (GMT), Jim Lesurf
wrote:

The whole idea of devices using RF over the mains under the pretense that
they are "not transmitters" is absurd.

No more absurd than the idea of using RF up to the 25m shortwave band
over telephone cables - but I'm able to post this message because it
works.

Rod.

In article , Roderick Stewart
wrote:
On Tue, 07 Jan 2014 09:21:37 +0000 (GMT), Jim Lesurf
wrote:

The whole idea of devices using RF over the mains under the pretense
that they are "not transmitters" is absurd.

No more absurd than the idea of using RF up to the 25m shortwave band
over telephone cables - but I'm able to post this message because it
works.


Not sure that's the same. At least telephone cables are meant to carry
signals. Dont they also have a specified impedance, etc, as transmission
lines? And are there no specs at all on how much of the net signals they
can radiate, etc? If they are as poor as mains home wiring would be at RF
I'm amazed it works at all over such long distances compared to inside a
home.

Whereas home mains wiring has no specs at all for impedance, has many
unbalanced spurs, terminates in unpredicatable nonlinear loads, etc.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

In message , Roderick
Stewart writes
On Tue, 07 Jan 2014 09:21:37 +0000 (GMT), Jim Lesurf
wrote:

The whole idea of devices using RF over the mains under the pretense that
they are "not transmitters" is absurd.

No more absurd than the idea of using RF up to the 25m shortwave band
over telephone cables - but I'm able to post this message because it
works.

And because telephone cables are reasonably well-balanced, it causes
very little interference (if at all) to those listening to RF
transmissions up to the 25m shortwave band. On the other hand, the mains
isn't, and it does.
--
Ian

On 07/01/14 17:26, Ian Jackson wrote:
In message , Roderick
Stewart writes
On Tue, 07 Jan 2014 09:21:37 +0000 (GMT), Jim Lesurf
wrote:

The whole idea of devices using RF over the mains under the pretense
that
they are "not transmitters" is absurd.

No more absurd than the idea of using RF up to the 25m shortwave band
over telephone cables - but I'm able to post this message because it
works.

And because telephone cables are reasonably well-balanced, it causes
very little interference (if at all) to those listening to RF
transmissions up to the 25m shortwave band. On the other hand, the mains
isn't, and it does.

The telephone wires are explicitly balanced, by being made as twisted
pairs. That balances them against environmental asymmetries.

The certifications for mains based data links are done with
unrealistically ideal wiring installations.