I need some help with this.
My electronics is real rusty.
I will start with the trim pot.
Mine has 3 leads and I was told to set it at 500K before making adjustments. I know that some of the leads go to the chip, but which ones?
Thanks, Andy
Turn it to mid-rotation to get 500K. Use the center lead and either of the ends. Ignore the one that's left... you don't need it.
John
Tying the loose end to the wiper reduces the size of the glitch if there's a momentary open. :-)
Cheers! Rich
Tying the loose end to the wiper reduces the size of the glitch if there's a momentary open. :-)
Cheers! Rich
And if you choose that 'loose end' to be the 'counterclockwise' side of the pot, 'blink frequency' will increase with clockwise rotation of the knob. A thing which is devoutly to be desired.
:)
--Winston
-- Looking at the pot from the front, the terminal on the right goes to pin 3 of the chip, and the center and left terminals to either pin 2 or pin 6 of the chip, or you can just short them together. Doing it that way makes the flash frequency increase as you turn the actuator clockwise. Damn fine looking schematic, BTW! Where'd you find it?
It was given to me along with the parts.
Andy
The project is to making a flashlight into one that flashes all the LEDs.
I will use it to act as a high visibility back light for daytime use on my bicycle.
Looks like I will have to get a project board to finish it.
I saw some at Radio Shack the other day.
I may have to use my bench grinder to narrow down the tip to work in those small spaces.
Andy
Later I would like to make a simple LED to act as a fake alarm light.
I would embed it into wood and use a step down transformer or batteries to power it.
Frequency decreases with clockwise rotation, yes?
--Winston
-- No. As the wiper is turned clockwise, looking at it from the front, the resistance btween the wiper and the clockwise end of the track decreases, increasing the frequency.
So "the terminal on the left goes to pin 3 of the chip, and the center and right terminals to either pin 2 or pin 6 of the chip, or you can just short them together (and connect them to either pin 2 or pin 6 of the chip)."
Correct?
--Winston
I've even seen fake surveillance cameras. ;-)
Cheers! Rich
John Fields:
Ah, right.
-- No.
If Andy's trim pot looks like either of the above, why wouldn't the left terminal be the 'clockwise' end?
--Winston
of
That's what I am going for.
Most folks are more careful around blinking lights. :-)
Andy
The asterisks represent the semicircular carbon track. What happens to the resistance between 2 and 3 when you turn the center shaft clockwise?
Ed
It becomes smaller. Hence the 'CW' symbol cast in near pin 3 on the right side. Because we don't know the part number of Andy's trimmer it is impossible to say which is technically the right answer. We all agree that connecting the rotor to the 'CCW' terminal will result in lower resistance with rotation in the CW direction.
That is the important bit.
--Winston
-- No, it isn't. What's important is that Andy know how to wire the thing up properly, and since I sent him the schematic and the parts to build it I knew that it was a single turn pot. Were you not so intent in finding fault you would have realized, from the context of the discussion, that there are other pots in existence (both single and multi-turn) which fit the description of operation given and realized your pot wasn't in that mix.
I did not realized that there was a criticism of the pot used.
I found a broken wireless controller that turns two outlets on/off.
It was broken, but I salvaged quite a bit of parts.
Andy
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