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1  Using Arduino / Installation & Troubleshooting / Re: Burnt Arduino Uno? on: August 31, 2014, 09:39:09 pm
How you powering the servo?
2  Using Arduino / General Electronics / Re: Ohm's Law. on: August 31, 2014, 06:01:48 am
No no all is good... ohms law was taught to me via the triangle method

V
IR


Cover one to get the other, I've never used Ohms/Volts only Volts/Ohms so that triangle was lying....

Noone's using ohms/volts!  buffer is a pure number ratio, so we have ohms/number.
In other words the resistance ratio is the same as the voltage ratio.
.


Good! I thought I was going mad .....   thank you clearing that up.
3  Using Arduino / Project Guidance / Re: use arduino to control an adjustable boost converter? on: August 30, 2014, 07:08:08 pm
If you can get > 10 amps from two lithium batteries. ..

I'm betting you'll have a few minutes not 10-15... what's the capacity? The best I've seen is around 1a/h unless you spend big bucks.
4  Using Arduino / General Electronics / Re: Ohm's Law. on: August 30, 2014, 06:53:05 pm
{ sad, resigned sigh}
Code:
Vout = (5.0 / 1024.0) * raw;

Not my code, copy and paste job.
5  Using Arduino / Project Guidance / Re: use arduino to control an adjustable boost converter? on: August 30, 2014, 11:47:21 am
2 lithium 4.2v batteries

Adjustable to 10amps at 10v.....

100watts from 2 lithium batteries (before conversion loss)
6  Using Arduino / General Electronics / Re: Ohm's Law. on: August 30, 2014, 11:38:43 am
No no all is good... ohms law was taught to me via the triangle method

V
IR


Cover one to get the other, I've never used Ohms/Volts only Volts/Ohms so that triangle was lying....
7  Using Arduino / General Electronics / Ohm's Law. on: August 30, 2014, 09:00:52 am
Code:
int analogPin = 0;     // potentiometer wiper (middle terminal) connected to analog pin 3
                       // outside leads to ground and +5V
int raw = 0;           // variable to store the raw input value
int Vin = 5;           // variable to store the input voltage
float Vout = 0;        // variable to store the output voltage
float R1 = 10;         // variable to store the R1 value
float R2 = 0;          // variable to store the R2 value
float buffer = 0;      // buffer variable for calculation

void setup()
{
  Serial.begin(9600);             // Setup serial
  digitalWrite(13, HIGH);         // Indicates that the program has intialized
}

void loop()
{
  raw = analogRead(analogPin);    // Reads the Input PIN
  Vout = (5.0 / 1023.0) * raw;    // Calculates the Voltage on th Input PIN
  buffer = (Vin / Vout) - 1;
  R2 = R1 / buffer;
  Serial.print("Voltage: ");      //
  Serial.println(Vout);           // Outputs the information
  Serial.print("R2: ");           //
  Serial.println(R2);             //
  delay(1000);
}

While not strictly a programming question hence why i'm posting it here..

Now, i'm a little confused here...

Code:
  Vout = (5.0 / 1023.0) * raw;    // Calculates the Voltage on th Input PIN
  buffer = (Vin / Vout) - 1;
  R2 = R1 / buffer;


I simplified it down to this...

5v  --------~~~~~100ohms~~~~~----------(2.5v)-----------~~~~(Unknown Resistor)~~~~------------GND

Vout =  (5/2.5)-1 = 1
Unknown Resistor = 100/1 =  100

am i missing something or is that correct?
8  Community / Bar Sport / Gas carrying charged particles on: August 28, 2014, 11:22:13 am
Basically I was thinking 2 balloons full of gas that  carries charge and make balloon capacitors?

I googled found little. .

9  Using Arduino / General Electronics / Re: 240vac Aussie Plug Wiring. on: August 26, 2014, 05:14:08 am
Ugh....

The point of this question is to find out if it matters which way round it goes...

(I'm chopping the plugs off of them all if you must know....)
10  Using Arduino / General Electronics / Re: Laser Woes on: August 25, 2014, 08:19:28 pm
I've seen toy rc cars with capacitors across the motor, i presume it's there to prevent a high voltage from the collapsing magnetic field ?
11  Using Arduino / General Electronics / 240vac Aussie Plug Wiring. on: August 25, 2014, 08:11:08 pm


Active
Neutral
Earth

That's your Aussie Plug 240vac.

Now most of the Xmas lights (10m 100 LED ropes) i'm a little concerned with how i should wire these EU (2 pin) plugs.... does it matter which way it's wired? (since there's no Earth)




Now these cheap LED rope light plugs...
12  Using Arduino / Project Guidance / Re: How to power the Arduino from a UK light switch on: August 23, 2014, 11:21:40 pm
I once used silicon thick gel to keep a 240v face plate attached to the walls lol just ran it across the top of the faceplate where it had come away from the wall as the screws had simply broke away from the walls, was that illegal? Lol
13  Using Arduino / Microcontrollers / Arduino Galileo on: August 23, 2014, 08:20:58 am
http://www.electronics-lab.com/blog/?p=30174

Arduino supported by windows? Win32  api? So it's a mini pc? With external io?
14  Using Arduino / General Electronics / Re: Bread Boards & wishful thinking? on: August 22, 2014, 09:51:44 pm
I think some kind of extension that simply pushes into the breadboard....

Think laptop and battery, slots in....

15  Using Arduino / General Electronics / Re: Base Resistors for 2N5551 from Arduino on: August 22, 2014, 10:33:05 am
Maplin is making quite a profit on these 1 watt leds....   smiley-money
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