> >try http://www.sandlabs.com/answers.htm
> >(verified as good before transmission of this note.)
>
> Yes, but there was a reason I specified passive decoding -- I don't
> want to have to power an IC or individual gates at the tower, nor do I
> want to have to protect them against static electricity/lightning EMP.
Right you are Pete.
Anyone can go to databooks or notebooks and copy 3-to-8 line
decoder systems. (Just like anyone can copy Motorola's
schematic of a MRF-150 amp, remove Motorola's name from the
schematic and fail to credit them, and list it under 600W amplifiers
on a certain Web page.)
The problems all come when you apply application note solutions
to the real world!
Using logic circuits is not only wasteful, it is poor engineering in
this application. The bulk of the components, by far, will be in
lighting protection and interface buffering. When you are all done,
you still need to have the same number of (or even more) relays!
You'd not only add fragile parts and components to interface and
protect the unneeded digital parts, you still need all (or more) of the
original relays!
Almost anyone can design (or copy) a complicated and fragile
system. Real engineering involves improving reliability and
simplicity while reducing cost.
73, Tom W8JI
W8JI@contesting.com
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
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