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1  Using Arduino / General Electronics / Re: Wiring Capacitors in Series on: September 01, 2014, 06:51:48 pm
The voltage will divide across the capacitors only with AC (alternating current), not DC.
2  Using Arduino / Motors, Mechanics, and Power / Re: Fan only spins when given 255 pwm using TIP120 on: September 01, 2014, 12:15:35 pm
Then something's up here, something dissonant.
3  Using Arduino / General Electronics / Re: Ohm's Law. on: September 01, 2014, 12:10:39 pm
for the arduino has an almost infinite input impedance ...

Not exactly.  That is, not always, not during sampling.

http://forum.arduino.cc/index.php?topic=65134.0

http://www.skillbank.co.uk/arduino/measure.htm

[ I didn't come in till the ADC discussion started. ]
4  Using Arduino / General Electronics / Re: Arduino gets restart when operating 12V Solid State Relay on: September 01, 2014, 10:16:53 am
Is the Arduino connected to the "18V", too?  In other words, are you using that for "V in"?

What is the 7805 being used for? Arduino 5V?

With nothing connected to the relay contacts (C, NO, NC) is there still a "reset"?

(Get rid of that 100Ω resistor between the coil and the FET.)

> > > You could try replacing the relay coil with a resistor & LED to prove that circuit works right (on, off, on, off,...)
It's called troubleshooting.
5  Using Arduino / General Electronics / Re: Arduino gets restart when operating 12V Solid State Relay on: September 01, 2014, 10:08:44 am
i have connected 100R in series with SSR just to limit current flow ...

Haven't seen a picture of your device, but you keep referring to it as an "SSR".
According to the schematic it is simply a relay.
(An SSR and a relay are two different things.)
6  Using Arduino / Motors, Mechanics, and Power / Re: Arduino, 5V relay, 220v: checking I'm not putting myself or others at risks on: September 01, 2014, 09:26:34 am
Here are some pics (attached) of my "SSR in a box."

It's not the last word in anything (and I welcome the hate.)
I can manage with such things, but it's not UL/CE/TUV - not the thing to have around small children or irresponsible adults.

I grew up in the UK late 50s / early 60s and I'm certain my Dad called it LINE.

Jim, I read their folk using "live" here often, there was some scolding and parry and thrust once (can't find it, the Search tool here leaves much to be desired.)
7  Using Arduino / Motors, Mechanics, and Power / Re: Arduino, 5V relay, 220v: checking I'm not putting myself or others at risks on: August 31, 2014, 07:39:51 pm
It's not called "Live". It's called either "Line" or "Hot".

In UK-topia they do call it "Live", that's their term.
8  Using Arduino / General Electronics / Re: Ohm's Law. on: August 31, 2014, 04:05:48 pm
Yes, each represents a range (of possibilities.)
Perhaps the attached will help.

9  Using Arduino / Motors, Mechanics, and Power / Re: Fan only spins when given 255 pwm using TIP120 on: August 31, 2014, 12:11:34 pm
With a "filter" you're smoothing  the PWM into a DC level.
I think that, if this "noise" bothers you, you ought to change the Timer so that it runs at an "ultrasonic" frequency.
Choose an output with a timer other than the one that will affect millis()

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

http://arduino.cc/en/Tutorial/SecretsOfArduinoPWM
10  Using Arduino / General Electronics / Re: Arduino gets restart when operating 12V Solid State Relay on: August 31, 2014, 09:43:26 am
I am using 16x2 LCD (6 pins)...

That's extravagant.  Save some pins --

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

http://www.electronics-lab.com/projects/mcu/015/
11  Using Arduino / General Electronics / Re: Arduino gets restart when operating 12V Solid State Relay on: August 31, 2014, 09:35:45 am
But glad I hadn't missed a trick and that flyback diodes were actually required on SSRs. I have been paying attention these last couple of years....

Just to be clear: they're NOT required (have no use there.)

In the absence of a decent question what can you do?

Jump on them for it?
So often there's less than full disclosure or the omission of salient details, but why the haste to offer a flurry of remedies that anticipate infinity?  
It's not like anyone is going to lose a commission.
12  Using Arduino / General Electronics / Re: Ohm's Law. on: August 30, 2014, 04:16:24 pm
OK.
It should not be seen as a DAC, where "0" would yield 0V.
I understand the error of my ways.

The ADC resulting "0" implies everything in the range of 0 to 1mV (1.024V/1024)
0x3ff is anything between 1.023 and 1.024V

With 5V then "0" is the range of 0 to 4.88mV and 0x3ff is the range of 4.9951 to 5V.



13  Using Arduino / General Electronics / Re: Ohm's Law. on: August 30, 2014, 03:17:15 pm
I'll go with the 1.024V reference.
Assuming that 00 0000 0000 is 0V then the divisor must be 1023.
(Vref / 1023 = volts per step)

If it was a 2-bit ADC then you'd divide the reference by three.

I'm showing my work (see attached.)
14  Using Arduino / Programming Questions / Re: for loop like basic? on: August 30, 2014, 12:26:15 pm
So, are we done here?

15  Using Arduino / Programming Questions / Re: for loop like basic? on: August 30, 2014, 11:56:07 am
It does, I was doing the same

Code:
byte x;
byte a;

const byte blinkpin = 13;

void setup ()
{
  pinMode (blinkpin, OUTPUT);
  Serial.begin(9600);
}

void loop ()
{
  for(x=0; x < 10; x=x+2)
  {
    digitalWrite(blinkpin, HIGH);
    Serial.println(x,DEC);
    delay(500);
    digitalWrite(blinkpin, LOW);
    delay(500);
  }
  delay(2000);
}
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