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  1. Feb 27, 2009 #1


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    I need to make a pulse of varing length. Either I need a VCR/VDR to control the length of a momo stable pules, or a VCO to trigger a preset monostable at different times.

    I have been trying to find some thing to do the job for me but havn't had any luck. The VCR2N/4N/7N made by Siliconix are no longer made, and I can't find any where that stock them or any thing similar.

    Can any one tell me where to get hold of something which will work?
  2. jcsd
  3. Feb 27, 2009 #2


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    Triangle wave fed into a comparator with an adjustable reference.
  4. Feb 27, 2009 #3


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    Staff: Mentor

    or a 74HC4060 with Xtal and a little decode logic...
  5. Feb 27, 2009 #4


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    Thanks for the help guys. I found a way to make a VCO from a 4046B.
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