lm 555 and 556 projects?

[pazuzu]

i noticed a write up for these on beavis audio, and i noticed some a pack of them a bunch of 555's and a 556 in my futurelec ic grab bag. any suggestions? i am looking for another project to start. preferably in the next 5 minutes.

[rousejeremy]

Try the Hysteresis Oscillator with the 555 and an Atari Punk Console with the 556.

[pazuzu]

cool. stepped tone generator it is. i was wondering if there was more of a use but i'll go with it. looks easy. a question on the pinout:

if you are looking at the ic so to be able to read it, where is "1" located?

[rousejeremy]

There should be a circle on the top left of the chip by pin one.

[rousejeremy]

There's also a 555 in the Uglyface. It's one of those "must build" effects.

[pazuzu]

ok cool man. i will check that out too.

[CynicalMan]

There's also a 555 in the Uglyface. It's one of those "must build" effects.

The schematic says that the 555 must be CMOS and lm555 isn't. I can't verify this but I doubt it would work

[pazuzu]

well actually it's ne555p. it has what apears to be a texas instruments logo and a part number 89an8nm, but the write up at beavis made it sound like this was the same as the standard lm555.

[CynicalMan]

That's not CMOS either. Datasheet:
http://www.datasheetcatalog.org/datasheet2/c/0hex3d1gxjejda7ur3y2toipkzfy.pdf

[pazuzu]

well there ya go. you know the learning curve on this shit is feckin brutal. 

all joking aside this is an extremely rewarding hobby, and i have already had someone ask me to sell them my altoids tin npn boost, but i turned them down. first project has sentimental value.

[earthtonesaudio]

The 555 is a really good chip to become familiar with.  It can do lots of things. VCO, PWM, pulse stretching/frequency division...

A couple things you can do with it that don't get much mention in the datasheet: R-S latch (using pin 2 and Reset), Inverting Schmitt trigger (tie pin 2 and 6 together, outputs available at pins 3 and 7).

Also, the standard configuration for the monostable is really not that different from the Schmitt trigger inverter-based RC oscillator, if you really look closely at it.

[pazuzu]

ok, thank you. that's a little over my head at th  spoint but i appreciate the response. i have built the atari punk console on the breadboard using the 556 but i am having trouble with the pots. if i am looking at them from the bottom with the terminals pointing left how should they be wired (top to bottom)? i am having trouble reading the schematic.

<edit> i just played with it some more, pulled a noob and just forgot to jumper my +/- over on the breadboard. it works. although i am still unsure of the pot wiring. is one terminal left disconnected? if someone could answer the above question for clarity it would still be appreciated. this is the schematic i am working off of:

[pazuzu]

well, i got it all figured out. not that impressed with the circuit. i have a much more useful noisemaker that cost me 1000$, my guitar. but it was fun to build the circuit.

[runmikeyrun]

a delay after this pedal makes a world of difference.

[Ice-9]

You could use 55 timer to build a monotone piano (aka Rolf Harris Stylophone)!!!

http://www.youtube.com/watch?v=YInxfBILAV8&feature=related

or the same circuit could be used to build an audible guitar tuner.