Path: utzoo!attcan!uunet!ncrlnk!ncrcae!hubcap!gatech!rutgers!att!alberta!calgary!amc-vlsi!dale
From: dale (Dale Wlasitz)
Newsgroups: sci.electronics
Subject: Re: 1Hz signals
Message-ID: <582@amc-vlsi.UUCP>
Date: 17 Oct 88 14:46:29 GMT
References: <2006@lll-lcc.llnl.gov>
Sender: news@amc-vlsi.UUCP
Distribution: na
Lines: 30
In-reply-to: rzh@lll-lcc.llnl.gov's message of 13 Oct 88 00:05:39 GMT


>......I'd like to use the 60Hz signal on the
>power transformer, and a MINIMUM of components to condition it and
>divide it down. 
>....

Since you are using the 4566 you're off and running! Just before we
get to that point though an easy method (cheap too) to isolate, drop
voltages etc and get a nice clean sharp edged signal as input to the 
4566 is as follows:

	1. Use an opto-isolator tied to your signal source. The bias
	   for the diode can be checked from your spec. books. On the
	   output tie the collector with a pullup to your +5v or
	   whatever your interface circuitry runs on.

	2. Square it up! use the output off the collector of the opto
	   as input to a 4093 or similar schmitt device to create nice
	   squared edges.

	3. Drive this to your 4566 and your off!!


It's only a couple of parts.........

Dale

Oh sorry, I've used Motorola opto's with the greatest of success,
that's not to say the HP or other brands are not as good or better.
The Motorola publication is #DL118R1.