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And here it is
(Google "multivibrator tutorial" or similar to get a more in-depth look at them).
Oops, just realized I didn't give the 555 any supply (that's what happen when you get interrupted by mundane stuff like dinner ) - Kicking myself and will change that as well.Won't be any major changes though - I'll update and repost, but its 3 a.m. so it'll be after nap-time
A potentiometer is a "potential divider" (metering out the potentials/voltages).A trimmer can be either a trimming potentiometer, with "trimming" meaning something to adjust once or rarely/from time to time, while a normal potentiometer is something you adjust often (like eg. the volume on a radio/HiFi).A trimmer can also mean a variable resistor, i.e. a resistor which is not used as a potential divider.Some trimmers are made as just variable resistors (to save a bit in large scale production), but they're mostly found in consumer electronics like clock radios, cheap radios and such. Usually, you just use trimmer potentiometers as variable resistors by shorting the wiper to one end (as in this schematic).
Quote from: TheDarkLord on November 19, 2011, 02:21:11 PMWhich of the first three products on this page would be the most suitable?Potentiometer #1 and #3 are regular carbon track potentiometers, so is #2, but with an added on/off switch (all the way counter clockwise the switch is off).
Which of the first three products on this page would be the most suitable?
If you want it to be continually adjustable, you could use something like #1 of course - in that case, use as short leads as possible and connecting the metal encapsulation to either ground or V+ may be a good idea, as it will keep it from picking up noise. If the leads should act as antennas, a small cap (~10..100pF) can be used at the board connection points.
Thank you That circuit looks much more complicated, but I'm always up for a challenge.
Could you just briefly explain what's happening with the timer, in terms of input, trigger, output?
OK, I see what a trimmer is now. For my purposes I'd rather use a potentiometer just so I'm able to have control over how much water gets dumped on me
So, if I use #2, then I won't need to install an additional switch for the entire circuit?
On the schematic you've said "20s - 72s". If I want this range to be slightly lower (maybe from 10s - 60s) what value potentiometer should I use?
I know the equation is there, but I'm having a little trouble converting with all the zeroes
I'll have to do some more reading into how it picks up noise - it's similar to how you told me I couldn't leave the base of Q2 'floating' earlier. It seems interesting, but I'm not able to completely understand the occurrence.And just to clarify, what is "pF" in terms of F? Like "uF" is micro-Farads..
Thank you so much once again I can honestly say that you're my role model - I want to be as knowledgeable as you are in this field. What is your profession anyway?