Maker Pro
Maker Pro

Looking for a small project to fill void

Wiginometry

Nov 29, 2017
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Nov 29, 2017
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Does anyone know a good small project that can be shoved onto a small (1 1/2" by 1 3/4") board

Preferably something involving 555, 556, or 358 chips if not that cool too just trying to use up old stock.
 

Wiginometry

Nov 29, 2017
40
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Nov 29, 2017
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I thought about that but i cant seem to think of a good practical use for one.
Other than entertaining the kiddos.
 

Wiginometry

Nov 29, 2017
40
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Nov 29, 2017
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Intercom.
Now that's something I can get on 'board' with...
Haha.... Ok so my humor is a bit dry but
"Now for something completely different" !!!!!

You wouldn't happen to have a schematic for the intercom in question would you?
 

AnalogKid

Jun 10, 2015
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https://images.search.yahoo.com/sea...ZWMDcGl2cw--?p=Intercom+schematic&fr2=piv-web

Many intercom circuits are a simple microphone amplifier with a switching arrangement to swap the inputs and outputs. More fun is a switchless, hands-free circuit:

Intercom.GIF

Q1 is operating as a variable current sink driver. It's output impedance is high enough for 2 or 3 stations. The next step beyond this is to replace Q1 with a Howland current source. With that, you can have many (and a varying number of) stations on a single intercom bus. Many TV, stage, and film productions sets use that type.

ak
 
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Wiginometry

Nov 29, 2017
40
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Sweet that looks like it'll keep me occupied for an afternoon or late night if insomnia hits...
 

Wiginometry

Nov 29, 2017
40
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I'm always game for more ideas or things that will help improve my skills.

Sometimes you have to fail to succeed.
 

73's de Edd

Aug 21, 2015
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Sir Wiginometry . . . . .

Just in case some . . . or ALL . . . . of that circuits Resistor /Capacitor values have slipped your mind . . . . . .

The rest of the story . . . . . .

https://www.eeweb.com/extreme-circuits/full-duplex-intercom

BTW with that stage being nulled out with R7 pot, I see that designs circuitry treatment of
C4 electrolytic polarity, being correct, as it is shown.


73's de Edd
 
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