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Re: [Amps] rotary switch - shorting/non-shorting

To: <>, <>,<>
Subject: Re: [Amps] rotary switch - shorting/non-shorting
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Fri, 31 Aug 2007 12:53:49 -0400
List-post: <>
> The break-before-make or make-before-break switches define 
> a different switch function.

In the USA they are primarily called "shorting" switches 
when dealing with rotary switches.
This is what messes some people up.

They think "shorting" means progressively shorting but in 
every case I've seen for rotary switches shorting has meant 
either the contact indexing or wafer is adjusted or designed 
to make with the new contact before the connected contact is 
dropped or the index is in the detent area, or the contact 
itself is wider and closer to the next contact.

Either way it lowers the voltage.

What you are calling "break before make" is really called 
non-shorting by rotary manufacturers, while "make before 
break" is called shorting.

I've looked through some off-shore catalogs and they appear 
to follow that guideline also.

So it looks like "pick-up-and-hold" or "progressively 
shorting" is what we generally want.

Drake, Heath, and Ameritron used a non-shorting Centralab 
switch with pick up and hold  rotor configuration in the 
tank inductor area. Ameritron used a shorting style wafer in 
the tuned input to reduce alignment problems.

73 Tom 

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