Show Posts
Pages: 1 ... 17 18 [19] 20 21 ... 145
271  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 03:27:34 pm
May be a cheap, go no go, Logic Probe.
272  Using Arduino / General Electronics / Re: Smoothing Capacitor value? on: March 24, 2014, 03:25:40 pm
Quote
these little guys
What guys?
Which capacitor are you referring to?
273  Using Arduino / General Electronics / Re: Small transformer on: March 24, 2014, 03:20:16 pm
May be modify one of these or something similar:
HERE
274  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 03:14:50 pm
Usually you include everything in a schematic (like a block, resistor, lamp etc.) including the load element.
275  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 02:47:53 pm
As a side note, you may want to investigate a ULN2803 driver ( also needs a collector resistor ).
On second hand, the o/p low might be too large.
276  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 02:33:47 pm
Sounds to me a simple NPN or PNP switch will do what you want.
277  Using Arduino / Motors, Mechanics, and Power / Re: Continuous servo rotation without for loop on: March 24, 2014, 02:30:22 pm
If you are asking if you can put your code in setup() which runs once at reset, then yes.
278  Using Arduino / Motors, Mechanics, and Power / Re: Wonder about the arduino output pin power on: March 24, 2014, 02:28:20 pm
USB will supply 5volts to the Arduino.
External voltage to the jack is turned into 5volts.
So the o/p on a pin will be very near 0 to 5 volt transitions.
If you are thinking of the current on the other hand, the Arduino o/ps are safe to support 20ma.
USB from a PC usually is a maximum of 500ma.
If you use external voltage try to keep it low, 7volts is best as the on board regulator may get hot.
279  Using Arduino / General Electronics / Re: basic soldering iron - tips and advice? on: March 24, 2014, 01:21:41 pm
Lead molecule is large for absorption, avoid cuts cover with bandaid, wash hands, use ventilation if concerned.
280  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 01:13:23 pm
A comparator may be a better choice for speed, eg LM339.
With the transistor, incorporate a collector resistor.
For simplicity I would use a transistor.
281  Using Arduino / Project Guidance / Re: Convert BCD to decimal for switch case on: March 24, 2014, 12:46:45 pm
The good thing about software is you can test things out for yourself.
Note: the top bits (6,7) of PORTB, UNO, are not connected to  i/o pins.
PORTB bit 0 is connected to UNO pin 8 while bit 5 is connected to pin 13.
So if you what to use the top 4 "Pins" this is bits 2, 3, 4 and 5.  Bits 6 and 7 are not usable.
val = PINB & 0b11000011;
For this example, switch case changes, you need to be looking at: 4,8,12,16,20,24,28,32,36,40 etc. 60 for the 16 possible combinations.

18000000UL I've got in the habit of adding UL to things that need to be unsigned long.

Edit:
Learn to make delays with the millis() function.
282  Using Arduino / General Electronics / Re: Resistors for 2N3904 Transistors and LED Strips on: March 24, 2014, 12:07:12 pm
Quote
So, I tried the approach without resistors and I was able to run the clock for hours without noticing any ill effects.
Sounds like you know what to do, but refuse to do it.
283  Using Arduino / Programming Questions / Re: programming on: March 24, 2014, 11:58:21 am
Sure, but before you start your project, google, LM34 Arduino, and servo Arduino.
Many examples on the WEB.
Go thru the basic examples that come with the IDE to get  some experience in programming.
284  Using Arduino / General Electronics / Re: basic soldering iron - tips and advice? on: March 24, 2014, 12:00:55 am
I use only 60/40 lead tin.
Never used lead free.
285  Using Arduino / Project Guidance / Re: Convert BCD to decimal for switch case on: March 23, 2014, 11:21:50 pm
Setup is ok

Edit:
Crossroads is the teacher.
Pages: 1 ... 17 18 [19] 20 21 ... 145