[sdiy] rotary switches in general

[Scott Gravenhorst]

music.maker at gte.net wrote:
>"Roy J. Tellason" <rtellason at blazenet.net> wrote:
>>On Tuesday 10 August 2004 06:16 pm, Tim Parkhurst wrote:
>>
>>> One alternative that I've seen used by others is to take a pot, hook it up
>>> as a voltage divider and run the voltage into a simple (2, 3 or 4 bit) A/D
>>> converter. The output of the A/D can then control an analog
>>> switch/multiplexer, transistors, or even relays. You'll need to add some
>>> indicator LEDs to provide user feedback, but this is relatively easy. A
>>> very simple "A/D" solution would be to use the LM3914 bar graph chip (10
>>> outputs = approx 3.5 bit resolution).
>>
>>Now *that* is kinda nifty!  :-)
>>
>>> This gives you the option of "bar" or "dot" modes,
>>
>>I guess the "dot" mode would be more useful in this context,  mostly?
>>
>>> and the outputs can be easily grouped together if you need fewer than 10
>>> positions. Given the cost of quality rotary switches, the A/D setup should
>>> be cost competitive, plus you now have a voltage controlled switch!
>>
>><...>
>>
>>> There are some other examples of how to run +/-10V signal through a 4051,
>>> but I can't find them right now. It can be done however, and I'll dig them
>>> up if you really need it.
>>
>>I'd be a little curious about this since the usual max power supply on those 
>>is 15V,  and +/-10V would appear to need a wider range,  unless I'm 
>>misunderstanding something here?
>
>
>You made me look.  Here it is from our friend René Schmitz:
>
>http://web.lan/wget_sites/www.uni-bonn.de/~uzs159/switch.html

OOFDA!  That URL will NOT work, it points to my local archive of the site.

The REAL URL is here: http://www.uni-bonn.de/~uzs159/switch.html

Crap, now I have to kill you all because you know my secrets...





>---------------------------------------------------------
>- Where merit is not rewarded, excellence fades.
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>- What good are laws that only lawyers understand?
>- The media's credibility should always be questioned.
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>
>-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
>-- Linux Rex         | RedWebMail by RedStarWare
>-- FatMan: home1.gte.net/res0658s/FatMan/
>-- NonFatMan: home1.gte.net/res0658s/electronics/
>-- Autodidactic Master of Arcane and Hidden Knowledge.
>

---------------------------------------------------------
- Where merit is not rewarded, excellence fades.
- Hydrogen is pointless without solar.
- What good are laws that only lawyers understand?
- The media's credibility should always be questioned.
- The only good terrorist is a dead terrorist.
- Governments do nothing well, save collect taxes.

-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
-- Linux Rex         | RedWebMail by RedStarWare
-- FatMan: home1.gte.net/res0658s/FatMan/
-- NonFatMan: home1.gte.net/res0658s/electronics/
-- Autodidactic Master of Arcane and Hidden Knowledge.