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961  Using Arduino / General Electronics / Re: Relays not resetting on: July 09, 2013, 06:48:09 pm
Thanks for the help.  I didn't even think about the SSRs being AC only.

When in doubt, ask your friends here (first.)
962  Using Arduino / General Electronics / Re: Relays not resetting on: July 09, 2013, 06:20:50 pm
They are AC solid-state relays.
Mechanical relays outputs don't care AC/DC, but SSRs are that way.
There are DC SSRs, but those in this board of yours are AC (AC only.)

You can switch the power to the power supply (assuming its powered from AC), but not the DC output/s.
963  Using Arduino / General Electronics / Re: Relays not resetting on: July 09, 2013, 06:09:33 pm
Are you switching AC with them, > 100ma?

[The spec states --  Load current: 0.1 to 2 AMP.]

> > >  You can't have "no load" and stick your voltmeter on the output/s and look for "120 or 0". 
964  Using Arduino / Motors, Mechanics, and Power / Re: Can I control these 2 coolers via PWM??? on: July 09, 2013, 06:04:07 pm
The only place for a Darlington, these days, is in a museum.
Their excessive VCE robs the load of voltage, they are encumbrances.
Find a better quality transistor, a "general purpose amplifier" with an IC > 200mA, as I recommended earlier.

I think the capacitor in parallel with the motor is rounding the edges to some effect.
If you don't have that diode in place then the capacitor (being a polarised device) is getting some rough-handling for it.
965  Using Arduino / Motors, Mechanics, and Power / Re: Can I control these 2 coolers via PWM??? on: July 09, 2013, 02:50:03 pm
The sound is the result of the PWM frequency (approx 500Hz).
Capacitors will not change that.

To get rid of that you will have to change the timer sourcing the PWM for a frequency higher than human hearing.
playground.arduino.cc/Main/TimerPWMCheatsheet.
966  Using Arduino / General Electronics / Re: Bluetooth (module) hardware question... on: July 09, 2013, 12:08:35 pm
Casually looking at it, Riva, that looks like the best write up I've ever seen.
967  Using Arduino / General Electronics / Re: LED bar Voltage visualiser on: July 09, 2013, 12:04:45 pm
A microcontroller isn't necessary.
Barring that... a bargraph driver IC or other semiconductors will be necessary.
968  Using Arduino / Project Guidance / Re: Adressing Led Strip on: July 08, 2013, 05:29:28 pm
The datasheet --
www.adafruit.com/datasheets/WS2811.pdf

The 8 bits of Red data, 8 bits of Green data, and 8 bits of Blue data get sent in msbfirst.
There's no clock.
A "0" is sent as a pulse of 0.5usec High followed by 1.2usec Low; a "1" is sent as a pulse of 2usec High followed by 1.3usec Low.
That's in "low speed mode".
A Reset is a Low held for at least 50usec (esp. between "frames".)

The tolerance for the waveforms is +/-  0.15usec.  Seems rigid.
You can't do that with digitalWrite and delayMicroseconds.
I'm guessing a little, but this probably involves dickering with one of the Timers.

So, there you have it - your work's cut out for you.
969  Using Arduino / Programming Questions / Re: Infrared Diode Wont work on: July 08, 2013, 11:14:21 am

Well, they don't "require" it; many can do with 100mA, but that's the outer limit (it's a max not a min.)
970  Using Arduino / Project Guidance / Re: Bluetooth? Robotics controller on: July 07, 2013, 09:56:17 pm
http://www.instructables.com/id/Andruino-A-Simple-2-Way-Bluetooth-based-Android-C/
971  Using Arduino / Motors, Mechanics, and Power / Re: DC motor effecting all pin voltages on: July 07, 2013, 04:36:14 pm
Those long wires to the ultrasonic aren't such a great idea (aerials).
972  Using Arduino / General Electronics / Re: 555 timer - failed at the first hurdle on: July 07, 2013, 04:32:15 pm
Pin 4 should be = supply volts
Pin 8 should be = supply volts
or there's a problem.

You should jumper the Gnd bus on the one side over to the one on the other side.
Then ground your caps on that rail/bus instead of running the jumper leads as you are.

If this is a CMOS 555 (7555 or LMC555) then it should run from a 9V battery OK.
If it's an LM555, a bipolar device, then it will suck (big transients on transitions) and will get hot depending on the load.

Placate the bypass crowd by placing a 0.1uF, from +V to Gnd on your power bus.
973  Using Arduino / General Electronics / Re: 555 timer - failed at the first hurdle on: July 07, 2013, 04:06:48 pm
Have some load on the output. 

  got "2K"?
974  Using Arduino / General Electronics / Re: 555 timer - failed at the first hurdle on: July 07, 2013, 04:04:46 pm
I think that an 8Ω speaker on the output is not a great idea.
I'd put a resistor in series; 100Ω, 220Ω, something like that.
975  Using Arduino / LEDs and Multiplexing / Re: 4 Chars 7-Segment with 74HC595 on: July 07, 2013, 04:02:15 pm
P.S.
What are milis?  smiley-roll

millis ()

Spend much time with the Arduino Reference do you?

http://arduino.cc/en/Reference/Millis
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