The UK Home Automation Archive

Archive Home
Group Home
Search Archive


Advanced Search

The UKHA-ARCHIVE IS CEASING OPERATIONS 31 DEC 2024


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: IR over cat5


  • To: ukha_d@xxxxxxx
  • Subject: Re: IR over cat5
  • From: "PatrickLidstone" <patrickl@xxxxxxx>
  • Date: Mon, 18 Feb 2002 20:04:53 -0000
  • Delivered-to: mailing list ukha_d@xxxxxxx
  • Mailing-list: list ukha_d@xxxxxxx; contact ukha_d-owner@xxxxxxx
  • Reply-to: ukha_d@xxxxxxx

--- In ukha_d@y..., "Ian Lowe" <ian@w...> wrote:
> I always thought that if you are using CAT-5, and you use one pair
for TX
> and a pair for RX, and common the grounds, then you can get a bit
of benefit
> from the twisted pairs..
>
> as the ground line and the signal line are exposed to (basically)
the same
> induced noise along the cable path, hence leaving the original
signal
> "untouched" (or less touched at any rate)

Ouch! It will work, but you're not getting any benefit from the
twisted pairs in this scenario. To get real benefit, you need to send
signal down one member of the pair and inverse signal down the other
(ie differential). Induced effects then cancel.

In RS232 land this is satisfied with RS4xx drivers - dead cheap to
knock up if you're handy with a soldering iron, but not at all
necessary in any domestic installation given the huge hysterisis
window.

Patrick



Home | Main Index | Thread Index

Comments to the Webmaster are always welcomed, please use this contact form . Note that as this site is a mailing list archive, the Webmaster has no control over the contents of the messages. Comments about message content should be directed to the relevant mailing list.