Show Posts
Pages: 1 ... 211 212 [213] 214 215 ... 260
3181  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Input on this oscilloscope please on: November 10, 2009, 12:37:15 pm
its about 704$ more expensive than mine

Its a nice unit, but I guess my question is,...  are you in a position where you would get good use out of such a machine?

TBH I really don't use mine a whole bunch, Its darn handy when I do so I am glad I have it, but also I got it for free (with the horrible repair task of plugging the crt back in), so its not a 700$ chunk of equipment collecting dust
3182  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Using LEDs question on: November 13, 2009, 12:47:12 am
ah! but dimmer is not the question, its how to reduce component count and still be safe!

ive got 16 right now running off of 4 resistors in a matrix, and the visible difference is negligible, its also running tru a 74164, that for testing that was set with 8 bits of data (1 nibble anode control, 1 nibble cathode) and never clocked or fiddled with again so all 16 are on at once with no cycling, voltages are fine and total current per row is as expected, individual currents on the led's haven't been measured but i am stubborn and will do it if need be
3183  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Using LEDs question on: November 12, 2009, 05:55:10 pm
so how does it work when making a matrix, i see it all the time where only a row is connected to 1 resistor and its peachy

but now today NO! every led needs a resistor no if's and's or but's
3184  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Using LEDs question on: November 12, 2009, 05:32:17 pm
here is another thread with the same topic

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1235523353

short answer is yes you can if the resistor can handle the wattage, but no you really don't want to
3185  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Pins and Resistor on: November 10, 2009, 06:36:47 pm
I know its not a led :smiley , but just goes to show always read the data sheet

3186  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Pins and Resistor on: November 10, 2009, 06:04:12 pm
i havent tried one on arduino, but the last time i hooked one of these things up directly to 5v it started to go, I caught it before it burned out and it still worked (all be it at diminished performance)

while it is true the basic setup schematic on this particular parts datasheet only shows a small r/c filter to smooth power
3187  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Pins and Resistor on: November 10, 2009, 05:54:53 pm
5 /0.005 = 1000 (not accounting for the device just looks like you were 1 0 off)

the datasheet i pulled for this part shows the standard config as G V O, if the dome is facing towards you

http://www.datasheetcatalog.org/datasheets/208/301092_DS.pdf

IR can be fun, so good luck!
3188  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Controlling 110V lamp using Arduino on: October 18, 2009, 01:11:10 am
relays are electromagnetic switches

http://courses.cs.vt.edu/~cs1104/CircuitDesign/Mechanical.2.html

solid state means it performs the same action with no moving parts
3189  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Swapping the voltage regulator on the arduino? on: November 03, 2009, 11:18:07 pm
dont be surprised when you do then.

and i too think your speed is a bit unthoughtful, shortcuts are ok when you understand why, but gun ho! fk that im not dumb at best can fry alot of work or money

at worse it could catch fire, stuff happens

crack open the oldest clock radio you can find at the thrift store and you will probally see some fat nasty diodes + a "ton o junk" for a couple bucks

I just got one last week for 1.25$, had 4 chunky diodes as a rectifier, a TI clock chip and a 4 digit 2 inch 7 seven segment display

+ screws, switches, 120v to 5 v low amp transformer w ac plug and some radio junk  smiley-razz
3190  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: SMD soldering practice? on: November 03, 2009, 12:12:49 pm
Quote
I find SMD soldering much quicker than TH. No leads to clip. No flipping of the
board to solder.

so do i, but i kinda go hybrid, surface mounting TH components to a piece of perfboard (well or pcb if i ever made any)

I always get mixed up fipping the board over and thinking of stuff in mirror
3191  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Arduino 5v motor on: October 31, 2009, 04:51:09 pm
I would not keep it directly hooked directly up to the chip, adding any load to the motor will probably cause it to draw more amperage than the pin can source causing damage

using a transistor like a switch you can turn the motor on or off with a digital pin, or control its speed with the pwm



(image from here, and the resistor on the base can be 1k)
3192  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Help with RGB LED Fire Effect on: October 30, 2009, 08:11:31 pm
sorry, i am doing a "head scratching" session myself and did not see that part or fully understand the question  :-[

the quickest thing that comes to mind is

sudo
Code:
int yellow = random(120) + 135);

analogWrite(ledPin1, random(120)+135); // RED
analogWrite(ledPin4, yellow);
analogWrite(ledPin5, yellow);

so that green and red can't over-mix each other

I dont have any rgb led's (oddly enough i do have a couple dual color red / yellow ones) or i would try it
3193  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Help with RGB LED Fire Effect on: October 30, 2009, 06:32:23 pm
well for a starter ...

yellow is a mix tween Red and green
3194  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Control a pager motor with Arduino on: October 29, 2009, 06:14:23 pm
to control direction you will need a H bridge

http://en.wikipedia.org/wiki/H-bridge
3195  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Arduino + Vacuum Tubes as a transistor on: October 19, 2009, 06:24:15 pm
1) amperage?
2) yes
3) tubes take considerable voltage to use
Pages: 1 ... 211 212 [213] 214 215 ... 260