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1  Using Arduino / General Electronics / Re: Inverse multiplexer? on: April 18, 2014, 10:25:54 pm
Analog or digital demultiplexer?
2  Using Arduino / General Electronics / Re: can I use duct tape on this project? on: April 18, 2014, 05:47:27 am
Yeah, one of my pet peeves is people treating WD-40 as if it were an oil, and duck tape as if it were permanent. And both as if they were panaceas.
3  Using Arduino / General Electronics / Re: can I use duct tape on this project? on: April 17, 2014, 06:20:02 pm
I vote for heat shrink. Duck tape (the fabric stuff) is a temporary thing. The glue dries out, the fabric falls apart. Electrical tape is not good for something this tiny, it is difficult to wrap around very small wires. Both tapes can creep under stress and expose wires.

Heat shrink.

Actual -duct- tape is aluminum tape, which is conductive.

If you hire someone to work on your furnace/ductwork and you see them using fabric tape, fire them. It falls apart quickly when exposed to heat, they should be using aluminum duct tape.
4  Using Arduino / General Electronics / Re: High Voltage Regulation on: April 17, 2014, 06:16:56 pm
Read up on how light dimmers work.

Line voltage and currents are very dangerous. No offense meant, but it is clear from your questions that you have very little knowledge of electronics. Perhaps it would be wise to first learn with projects that are not easily fatal.
5  Using Arduino / Project Guidance / Re: Blocking -VDC on: April 17, 2014, 05:59:33 pm
retrolefty: I'm going to identify the motor terminals by negative and positive, so-called because they are negative and positive with reference to each other when the motor is being turned in the "forward" direction.

Connect a couple of 1k resistors in series from 5V to ground. 10uF capacitor from the center point to ground.

Connect the negative terminal of the generator to the center point of the resistors. That is at 2.5V.

Connect a 100 ohm resistor across the motor, from positive to negative. Connect a 0.1uF capacitor also across the motor positive to negative.

Connect the positive lead of the motor to a 1k resistor, the other end of the 10k resistor goes to a 0.1uF capacitor, other lead of the 0.1uF capacitor to ground. Connect the end of that 10k resistor to an Analog input pin on the Arduino.

Now when the motor does not spin, it is at 2.5V. Motor spins "forward", it adds to that voltage. Motor spins "backwards", it subtracts.

I might also connect shottky diodes across that Analog input pin such that they are forward biased if that voltage goes outside the bounds of ground or 5V.

Play with the values. This is all off-the-cuff.
6  Using Arduino / Project Guidance / Re: How to increase the dc motor's speed(andFrequency)value more than255(and64KHZ)? on: April 17, 2014, 03:24:15 pm
Read all the button states at the beginning of your code, then perform all tests.
7  Using Arduino / Project Guidance / Re: Blocking -VDC on: April 17, 2014, 03:22:31 pm
Sort of a Wheatstone bridge reversed.
8  Using Arduino / General Electronics / Re: criticism over my circuit.. on: April 17, 2014, 03:21:36 pm
Yes, missed the point of extremely low power draw from the 5V line, and that it isn't an output pin but the 5V supply itself.

Naturally, the most clueless are also the most violently insulting.

But then, was there any more description than that?
9  Using Arduino / Project Guidance / Re: Blocking -VDC on: April 17, 2014, 02:08:26 pm
I turned the box inside-out.
10  Using Arduino / Project Guidance / Re: Blocking -VDC on: April 17, 2014, 02:08:02 pm
A rotary encoder is just two switches. It works by having the switches get activated in quadrature.

If you look at the output:



http://playground.arduino.cc/Main/RotaryEncoders

You can set up your own quadrature rotary encoder. Two optical disks rotated so as to be 90 degrees out of phase with each other.
11  Using Arduino / General Electronics / Re: Will this voltage doubler works with DC input? on: April 17, 2014, 01:58:27 pm
How much current? That IC will work to generate -3V from +3V, which  you could then connect the -3V to the common (ground) of your circuit ONLY IF the battery is not connected anywhere else but to the ICL7660 and the ground of the ICL7660 MUST NOT be connected to your circuit ground.

But this won't supply much current. The equivalent series resistance goes up as the input voltage goes down.
12  Using Arduino / Project Guidance / Re: How to increase the dc motor's speed(andFrequency)value more than255(and64KHZ)? on: April 17, 2014, 01:51:14 pm
Go, Grumpy_Mike.

This is why I'll continue to say that delay() is one of the worst things to teach a newbie as a first lesson. It has its uses.
13  Using Arduino / Project Guidance / Re: Blocking -VDC on: April 17, 2014, 01:48:28 pm
Just commenting on the idea of using a motor as a generator to determine direction:

Connect one terminal of the motor to a voltage divider at Vcc/2. Connect the other, through the appropriate resistors and diodes to protect the Arduino and capacitor to smooth the signal, to an Analog input pin.

Motor spins one way, voltage>2.5V. Motor spins the other way, voltage<2.5V. You could connect a second Analog input to the voltage divider to get an accurate read of zero speed voltage.

Load the motor down with the right resistor across it, and you can probably get a reasonable indication of speed, too. The resistor should go right across the motor.
14  Using Arduino / Project Guidance / Re: [ Guidance Needed ] How to make my own Arduino. (for USB com) on: April 17, 2014, 01:38:16 pm
ATMega8, sure. This page covers using it:

http://playground.arduino.cc/Learning/AtmegaStandalone
15  Using Arduino / General Electronics / Re: How do I replace a moral rectifier part? on: April 17, 2014, 12:02:30 pm
If you can get more Magic Smoke, you can repair it.
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