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31  Using Arduino / Project Guidance / Re: Need Help controlling 4 DC Motors, 5000 RPM, 115 V. 1/15hp on: April 11, 2014, 10:23:00 am
1/15HP is only about 50W. That's a pretty weak motor compared to the typical brushless motors used in RC.

I wouldn't say that brushed, 115V DC motors are uncommon but the motor controls available typically need 120V AC input. Finding a control for a battery application is going to be a problem -- I've never seen one. Also, brushed DC motors of this type are typically biased to spin faster in one direction than the other so if you do need to get that kind of speed balance you're probably looking at the wrong type of motor.
32  Using Arduino / Motors, Mechanics, and Power / Re: Arduino Micro - driving relays for seat warmer on: April 11, 2014, 09:26:31 am
See http://arduino-info.wikispaces.com/ArduinoPower#OI for help on wiring it using the optical isolation. With that scheme you're powering the relays with the car's 12V and it only needs ~2ma from the Arduino, per relay.
33  Development / Other Hardware Development / Re: List of tools for surface mount work on: April 10, 2014, 08:50:41 am
I don't like those vacuum pickup pens either. Much easier to use a tweezers.

The really small tips for soldering irons aren't that easy to use. Unless you're working with very small pins like on a TSSOP (smaller than SOIC) you should stick with the "normal" sizes.

Someday I hope to build a custom "hot plate", about 15cm square, for doing reflow. A toaster oven sounds like a good idea if you're using solder paste/stencils but I'd like to have something that I can reflow on and still be able to manipulate the parts by hand.
34  Using Arduino / General Electronics / Re: Running super bright IR LEDs at 38khz off PN2222 on: April 09, 2014, 02:10:31 pm
PN2222 is plenty fast (any transistor is). Not even a consideration until you're in the MHz range.

Can you provide details on what LEDs, resistors, voltages you're dealing with? A schematic of precisely what you're using is what is needed.
35  General Category / General Discussion / Re: Are you legally allowed to edit your own homes wiring? on: April 09, 2014, 10:12:33 am
In the US the National Electric Code disallows an individual to adjust mains wiring unless they are a licensed electrician. I'm not sure how strict that rule is, e.g. if it disallows replacing a light fixture or such, but y'know.
36  Using Arduino / Sensors / Re: can I run 2 rotary encoders at the same time? on: April 09, 2014, 01:14:17 am
AdaEncoder will do it.

https://code.google.com/p/adaencoder/wiki/Usage
37  Using Arduino / General Electronics / Re: Battery charger on: April 08, 2014, 07:17:49 pm
3.7V (or 3.6V) is the "nominal" voltage of the battery. Lithium batteries are charged to 4.2V, and that peak voltage spec if the one you need to concern yourself with. I'm not going to flat out guarantee it's 4.2V for this particular battery, but more than likely it is and the charger should work with it fine.
38  Using Arduino / Motors, Mechanics, and Power / Re: Advice for ESC's on: April 07, 2014, 11:47:46 am
Scroll down on the page.

Quote
Note: A user manual is available under the files tab, these are no ordinary ESCs! Please take the time to read the manual before using them.
39  Using Arduino / Sensors / Re: Weight Reading Code for 2 Scales on: April 07, 2014, 10:38:16 am
You want to avoid performing analogRead() on multiple pins in quick succession, because, yes, the readings from one pin will be noticeable on other pins. The simplest solution is to perform two analogReads() on a given pin and discard the first result.
40  Using Arduino / Motors, Mechanics, and Power / Re: Advice for ESC's on: April 07, 2014, 10:27:39 am
Try the AfroESC at hobbyking.com. It's important to have documentation on how to program the ESC, or if nothing else at least you get the connectors with it.
41  Using Arduino / LEDs and Multiplexing / Re: Using LED driver with Arduino on: April 05, 2014, 11:57:48 am
The CAT4137 is a switching driver. It will boost the input voltage to light the 5 LEDs when placed in series. It's a bit more complex of a circuit with the inductor and schottky diode being something most people don't have on hand, but it'll do what you want.

If you're worried about the varying voltage from the LiPo, why not just monitor the battery voltage with the Arduino and adjust output appropriately?
42  Using Arduino / General Electronics / Re: Where can I buy an Electro-Permanent Magnet? on: April 05, 2014, 11:38:55 am
http://copter.ardupilot.com/wiki/common-electro-permanent-magnet-gripper/
43  Using Arduino / Sensors / Re: How to determine GPS accuracy? on: April 05, 2014, 11:25:59 am
Quote
Again it wanders off. The data shows i was using between 50 and 85 satellites all the time.

Really? I wouldn't think that there are that many sats in view at any given time?

There's not even that many satellites in orbit (around 27 right now).
44  Using Arduino / Motors, Mechanics, and Power / Re: nema17 stepper window shades, 150mAh LiPo? on: April 04, 2014, 06:46:20 pm
how about a AA lithium ion like this?  it says 50w circuit max?  if that's even close to accurate, I'm sold on the battery size of AA.

Those specs are overly generous; that would be a 13A discharge. Compare to: http://www.all-battery.com/li-ion14500rechargeableaasize37v900mah.aspx which is rated at just 160ma discharge.
45  Topics / Robotics / Re: Arduino and complex robots? Possible? on: April 04, 2014, 05:53:37 pm
I'm not saying that you can't build a pretty complex robot on an Arduino. As an example, the Ardupilot guys have done a really impressive job jamming full autonomous control into an ATMega2560. Personally, though, my programming is very unimpressive and I could never cram so much into so little space, especially with all the time-critical tasks involved. It's from that perspective that I would recommend something like a Pi to act as the brains of the operation.
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