Towertalk
[Top] [All Lists]

[TowerTalk] Decoding BCD with passive circuit

To: <towertalk@contesting.com>
Subject: [TowerTalk] Decoding BCD with passive circuit
From: VE6JY Don Moman" <ve6jy@freenet.edmonton.ab.ca (VE6JY Don Moman)
Date: Fri, 21 Dec 2001 23:53:06 -0000
Hi Pete

If you're looking to minimize the number of control cables, then a BCD
format like I built some time ago to switch up to 16 beverages from a 4 wire
system would work.  You "encode" it at the switch with diodes.  You need a 4
deck 16 position rotary switch  or some BCD thumbwheel types.  Or something
as simple as 4 toggle switches - but  then it's hard to scan thru the
positions.  At the far end you build a number of SPDT antenna relays,
arranged in a "Christmas tree" style fan out to handle the "decoding".  In a
4 line BCD arrangement, the signal will go thru 4 relays.  For a receive
only situation, - my situation - this was quite simple and cheap to build
using inexpensive sealed relays..  If you are dealing with high power
transmitting, more attention and cost would have to go into to the relay
design.

I don't have a sketch or a web site, but I'll draw it on a napkin for you at
Dayton next year, hi!

73 Don
VE6JY
>
> 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
>



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
Problems:                 owner-towertalk@contesting.com


<Prev in Thread] Current Thread [Next in Thread>