The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
From: Roger Johansson
Subject: Re: Reed Switch "dead spot".
Date: Mon, 02 Sep 2002 18:25:10 +0200
NNTP-Posting-Host: dialup4-54.home.se (18.104.22.168)
X-Newsreader: Forte Agent 1.8/32.553
James Meyer wrote:
>>How about this? use two reed switches place in 90 degree offset and
>>electrically in parallel so any one switch on would close the circuit.
> How about this? Place the reed switch vertically at the center of the
>square and use a "normal" magnet with the poles oriented up and down in the
Wouldn't it be a lot simpler using electrostatic sensing, or
Imagine a pcb-board as big as a chess board. Etch circles divided in
the middle on every square. If a chess piece with al-foil in the
bottom is placed over such a pattern it will short the two halves of
the square capacitively, which can be sensed electronically.
The pcb-board can be painted with black and white color, so the
distance between the piece and the copper is the thickness of the
paint, which gives good capacitive coupling.
Mechanically this is a lot simpler than putting magnets in the pieces
and mounting lots of reed switches.
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup