[TowerTalk] Decoding BCD with passive circuit

Chris BONDE ve7hcb@rac.ca
Fri, 21 Dec 2001 18:27:29 -0800


I would like to learn more.  However, I take umberance with "Binary Coded 
Decimal is same as HEX only it rolls over at "9" "
Decimal Heximal Octanal ae all differnet systems.  I donot know what the 
same as is.  There are differnent base systems.  I remember some of this 
enought to think that the quated part is in error.

However, the gist of the message is good.  I further have not learned the 
"new" stuff and would like to do so.

SO what the heck is a pull up or a pull down risistance. (Not thinking of 
anything sexual)

Chris opr VE7HCB

At 05:40 AM 2001-12-22 -0500, alex wrote:

>BCD or Binary Coded Decimal is same as HEX only it rolls over at "9"
>Thus, you have to decode 9 combinations of 4 bits. Not hard but hardware
>intensive as diodes take a lot of space. You need pull-up and pull-down
>resistors to
>create "AND" and "OR" gates.
>An elegant approach is to use a PIC micro to do the stuff you need. It costs
>a dollar or two and the development environment is free.
>
>If you need help, I can help set you up :)
>
>If you have a FAX, I can send you a diagram for the diode decoder you want
>to have :)
>
>Alex
>
>
>===================================
>If we can accept the notion that GUNS are
>the killers and not the people, why is it that
>we can not accept the idea that CARS are
>the speeders and not the drivers?
>
>Alex, trying to understand the world around.
>
>==================================.
>
>----- Original Message -----
>From: "Pete Smith" <n4zr@contesting.com>
>To: <towertalk@contesting.com>
>Sent: Friday, December 21, 2001 3:15 PM
>Subject: [TowerTalk] Decoding BCD with passive circuit
>
>
> >
> > I'm told that this can be done with a diode matrix to power switching
> > relays.  Can anyone point me to a reference, preferably on the web, for a
> > basic circuit?  Application would be in remote antenna switching.
> >
> > Thanks!
> >
> > 73, Pete N4ZR
> >
> > The revised World Contest
> > Station Database
> > is online at www.pvrc.org
> >
> >
> >
> >
> >
> > AN Wireless Self Supporting Towers are now available!  Windloading tables,
> > foundation diagrams and charts, along with full details are now at the
> > AN Wireless Web site:  http://www.ANWireless.com
> >
> > -----
> > FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
> > Submissions:              towertalk@contesting.com
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> >
>
>
>AN Wireless Self Supporting Towers are now available!  Windloading tables,
>foundation diagrams and charts, along with full details are now at the
>AN Wireless Web site:  http://www.ANWireless.com
>
>-----
>FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
>Submissions:              towertalk@contesting.com
>Administrative requests:  towertalk-REQUEST@contesting.com
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AN Wireless Self Supporting Towers are now available!  Windloading tables,
foundation diagrams and charts, along with full details are now at the
AN Wireless Web site:  http://www.ANWireless.com

-----
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
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