[aprssig] Timer Circuit Needed

[Dave Baxter]

For that sort of time period, best to avoid 555's and the like.  Do it digitaly with a counter and faster clock gen, even if that "counts" once every few seconds, it's going to be a lot easier to implement, and a lot more stable and reliable.   Even the simplest PIC (or AVR) could do the job with minimal code.  But still needs carefull design etc.
 
Good luck.
 
Dave G0WBX.
 

________________________________

From: Chris Kantarjiev [mailto:cak at dimebank.com]
Sent: Fri 25/05/2007 17:51
To: aprssig at lists.tapr.org
Subject: Re: [aprssig] Timer Circuit Needed




There's a nice collection of 555/556 applications at

http://home.cogeco.ca/~rpaisley4/LM555.html

The three-stage cycling timer circuit is something like
what you're after (with an extra cycle).

73 de chris K6DBG




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