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166  Using Arduino / General Electronics / Re: Homemade button to test how hard it was hit on: November 28, 2012, 09:15:06 am
If you want to tell how hard a hit is you need to set some kind of range. You can use a spring and a pot to tell how hard the hit is
167  Using Arduino / General Electronics / Re: Best way to get a general electronics education. on: November 26, 2012, 11:36:44 pm
There one thing for sure learn the basics first and then try to keep up with the rest by reading. This stuff changes so fast you could waste 4 years learning about stuff you'll never see agin. I remember when I made a tube radio and radio shack sold the tubes. Point to point wiring those was the days. But it was like a year later that I started reading about transistors and then by the time i got up to speed what happen? Well what you think dang here come's IC with lots of parts in them
one chip and a handful of caps and resistors bang you got a amp and a receiver.

So lot's of reading to stay on top. I took a 3 day test to get a job in a plant working
with PLC for temp and motor and valve controls and if it was not for trying so stay up to date I wouldn't have passed it.    

Looks like JoeN is off on a good start and with a lot of good reading he could get where he want's to be. College is great I went back to finish my EE but my Wife died and I now have Two kids to take care of it was to much at one time to deal with. Good luck JoeN which  way you go.  
168  Using Arduino / General Electronics / Re: Dead Bug and Manhattan Prototyping on: November 26, 2012, 10:59:21 pm
I've made the header pins stronger with glue and some fine copper wire that lets me fill the holes with solder on the backside. I have has them pull the pads two.
But it works ok   
169  Using Arduino / General Electronics / Re: Dead Bug and Manhattan Prototyping on: November 26, 2012, 10:40:06 pm
Here a real time clock board I made it works is about all i can say
170  Using Arduino / General Electronics / Re: 4-20ma output from Arduino on: November 26, 2012, 12:20:17 pm
The work been done and ready to run .
171  Using Arduino / General Electronics / Re: 4-20ma output from Arduino on: November 26, 2012, 11:00:31 am
Here look like a workable idea
172  Using Arduino / General Electronics / Re: 4-20ma output from Arduino on: November 25, 2012, 10:07:17 pm
It don't look like any one reads any thing that's posted and start dumping out Idea's

First this is a loop you power this on the high side with power able to output more then 20mA at 24 volts the transmitter reads say a temp of 10 C and that means it needs to lower the low side to 5mA then the receiver which is a 250 ohm resistor Is read and show 5 mA the uC then tells you the reading is how these work. 
173  Using Arduino / General Electronics / Re: Connecting strange wiper motor, help selecting diodes (or other suggestion) on: November 25, 2012, 08:57:06 pm
It's a wiper motor I've seen one just like it on a old chevy dump truck. It's old like me.
174  Using Arduino / General Electronics / Re: 4-20ma output from Arduino on: November 25, 2012, 08:46:47 pm
Here a little reading on this http://www.bapihvac.com/CatalogPDFs/I_App_Notes/Understanding_Current_Loops.pdf

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The transmitter is the heart of the 4-20 mA signaling system. It converts a physical property such
as temperature, humidity or pressure into an electrical signal. This electrical signal is a current
proportional to the temperature, humidity or pressure being measured. In a 4-20 mA loop, 4 mA
represents the low end of the measurement range and 20 mA represents the high end.
BAPI specifies the power to our current transmitters as a range, 15 to 24 VDC for a humidity
transmitter or 7 to 40 VDC for a T1K temperature transmitter. The lower voltage is the minimum
voltage necessary to guarantee proper transmitter operation. The higher voltage is the maximum
voltage the transmitter can withstand and operate to its stated specifications
175  Using Arduino / General Electronics / Re: Connecting strange wiper motor, help selecting diodes (or other suggestion) on: November 25, 2012, 02:35:37 pm
If the wiper motor draws 25 amps it's bad almost any of the never use over a 15 amp fuse and 10 amps in newer cars is the normal.
Quote
Current. The minimum required current for the motor is 1.6 amps at 70 rpm, 0.9 amps at 41 rpm (and 4 amps if you elect to run it at 106 rpm, see note on the next page). These current ratings are for the motor spinning with no load. As you add mechanical load, these numbers can increase dramatically, doubling or even tripling under a heavy load. (When testing for torque, I found the motor to draw close to 14 amps in a stalled condition.) This factor must be taken into account when selecting a power supply. Since the motor will only use what it needs when it comes to current, it's best to provide a source with a higher current rating than you think you might need. I would recommend a 5 amp or greater supply to handle most circumstances.
And most stuff you find on the net say a 5 amp supply will run most any of them there not a power house of a motor
Quote
Contrary to what some believe, the wiper motor does not oscillate back and forth, it rotates continuously in one direction like most other motors. The rotational motion is converted to the back and forth wiper motion by a series of mechanical linkages. Here's a page that shows how this works in a car http://auto.howstuffworks.com/wiper1.htm

This type of motor is called a"gearhead" or "gear motor" and has the advantage of having lots of torque. My unscientific test (using one wiper motor and a torque wrench) found that at 12 volts, on high speed, the motor has 13.5 pound-feet and on low speed, has 17.5 pound-feet of torque.

Here a nice link http://www.scary-terry.com/wipmtr/wipmtr.htm
176  Using Arduino / General Electronics / Re: Connecting strange wiper motor, help selecting diodes (or other suggestion) on: November 25, 2012, 12:47:34 pm
Well I can tell you one thing for sure that's a wiper motor. Looks like a older chevy
It should have wiring like this Low and high.  So you end up with 5 wire

Ground and supply and then 3 for speed changes.  A little arm slipped over the shaft and had a bolt that locked it to those spines.

More then likely wired like this  
177  Using Arduino / General Electronics / Re: generating a -10v...+10v control signal from an arduino on: November 24, 2012, 08:28:53 pm
If you want to guess a 1k to 2.2k would be better if you want the right one. Read these
http://www.physics.unlv.edu/~bill/PHYS483/transbas.pdf
 http://www.rason.org/Projects/transwit/transwit.htm
178  Using Arduino / General Electronics / Re: Connecting strange wiper motor, help selecting diodes (or other suggestion) on: November 22, 2012, 11:47:29 pm
Sounds to me like you have a window motor not a wiper motor.

Window motors have gears on them wiper motors don't have any that you can see.
179  Using Arduino / Programming Questions / Re: Help for newbie programmer :) on: November 22, 2012, 11:24:12 pm
No one said
Quote
stupid
He said that the OP should of done some reading up on this And to fix the problem of having to much code running in the ISR

Interrupts are not a fix for poor coding if you layout the flow of your code to handle
time slots it's easy to get done what you want to happen.

Here some good stuff about this http://arduino.cc/forum/index.php/topic,119801.0.html
180  Using Arduino / Programming Questions / Re: Help for newbie programmer :) on: November 22, 2012, 09:45:41 pm
Here It's not to hard to find
Quote
In summary,

Arduino Serial uses: Data_bits=8, Stop_bits=1, Parity=None, Flow_control=None. This is fixed and you cannot change it when using Serial. Set your PC side accordingly.
Choose a baud rate that is safe from UART buffer overflows and HardwareSerial buffer overflows for your code.
Write short ISRs to prevent UART buffer overflow.
Dangling pins with attached ISR may cause fake and random interrupts that can interfere with system clock and cause UART buffer overlow.
Write loop() carefully to check and read Serial as soon as possible to prevent HardwareSerial buffer overflow.
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