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361  Using Arduino / Project Guidance / Re: Sparkfun Keypad Defective?? Pictures included on: March 12, 2013, 07:02:14 pm
You won't need external resistors or diodes because the library uses the internal pullup resistors and additonally ensures that all unused column pins are high-impedance

Also if you download the Keypad library, why not just use one of the other examples to test your keypad?

I'm thinking it must be my arduino uno that's the problem. I tried the examples but none of them seem to work. I connected my multimeter to pins 2 and 3 and read -.005 volts and when I pressed button 1 the multimeter instantly went to zero volts. So do you think my arduino is bad?

You want to be measuring resistance, not voltage.
362  Community / Bar Sport / Free computer power supplies, hard drives, and CD drives on: March 12, 2013, 06:44:36 pm
I just spent my day ripping apart old computers to separate the metal ($$$) from the PCBs. I have been throwing them away, but I just happened to think some people might want to turn them into desktop units. They're mostly older units, 90W - 300W. Some ATX, some not. If anyone wants one to use for a desktop power supply, just let me know. I can probably fit them in a medium flat rate box @ $12.35

I have no problem shipping internationally, but you could probably buy a new one for the cost of shipping alone.

EDIT: I also have a ton of 1 - 40gb hard drives, and some DVD/CD drives. I noticed some people use them for the stepper motors inside? The hard drives would fit in a small flat rate box at $5.80, the dvd drives would probably have to go in medium sized boxes. If you live in the northeastern United States, it would probably be cheaper to ship regular instead of flat rate. It would save some of this stuff from going to the landfill.
363  Community / Bar Sport / Re: A rare customer indeed, bargaining on a quote ! on: March 12, 2013, 01:38:20 am
Our financial year starts on July 1, at least in my part of USA. That means hurry up to spend down budget before the spring semester ends.
Our financial year begins April 1st so now is when all the road repair projects start, to ensure the budget is fully spent. 4 lots of roadworks have sprung up in the last week for my journey to work.

We have to wait on the weather here for major work. But the minor patching has started already.

Its always the spring and fall for us. Who cares about students? Gotta make sure we don't inconvenience the tourists. Its funny watching them rapidly speed up after the first cold-snap though. 4 months to paint the first bridge, then the next 8 bridges are finished in 2 weeks.

Whoever came up with the "spend it or lose it" system should be made an example of in the town square. So much wasted spending. We have an athletic department buying new everything because they need to spend it or they wont have enough next year, meanwhile our classrooms still have 10 year old textbooks because they can't obtain the funds needed for new ones. Last year our town manager took excess funds from one of these wasteful accounts at the end of the year, and used it to pay off our debt. The rest of the council wanted to crucify him, the taxpayers told them to go pound sand.
364  Using Arduino / Project Guidance / Re: Covering robot with metal on: March 08, 2013, 09:23:34 pm
You can get Plastidip in an aerosol spray can and use that.
365  Community / Bar Sport / Re: USPS out to kill hobby shipping on: March 07, 2013, 07:56:53 pm
There are now more ebay sellers in the USA offering free shipping on these cheap stuff since they buy them from manufacturers and ship huge quantity cheap and then sell them in the USA. On the other hand, we micro-businesses can't get any discounts. Any solution?

I wonder if they would accept some kind of bulk order similar to how OSHPark does their circuitboard orders. We all use the same account to get shipping quotes.
366  Using Arduino / Project Guidance / Re: Automate start/stop of a power generator on: March 05, 2013, 12:51:22 pm
It requires a foolproof method of ensuring that the generator cannot be connected to the outside supply.

This is not necessary true, not even from day one we use electronic. we got AC from AC power grid, in the grid there are a lot of power plants/generators interconnect each other, all is need is sync. The tech behind is power grid feed-in.

for people installed solar panel,  solar power grid feed-in is very popular and profitable since utility corp pay for feed back power. The device is Grid-tie inverter.


The issue is, when you lose power the power utility company will send out people to repair it. Those people flip a breaker at the pole, so they know THEIR generators are not providing any power to the section of line they are working on. If you don't have a transfer switch or disconnect, YOUR generator can be sending power down a line that the workers think is off. Your generator could severely injure or kill someone working on the power lines. Do you really want to take that chance?
367  Using Arduino / Project Guidance / Re: a screw hinge to adjust angle? on: March 04, 2013, 06:10:49 pm
If you mount them on a bracket with a hinge, you can stick a machine screw through the hinge or bracket, with a nut on the back to adjust height.
368  Community / Bar Sport / Re: Your latest purchase on: March 04, 2013, 06:06:47 pm
I finally bought an ISP for burning bootloaders, lol. Its apparently based on the USB ASP. Cost $7 on ebay.

I also bought a used server rack with UPS, 6 servers, a DAS, and a bunch of other junk. I'm probably going to use it to test an arduino based datacenter monitoring system.
369  Using Arduino / Project Guidance / Re: sending sms from arduino using free sms website... on: March 03, 2013, 01:37:58 pm
When you use one of these services to send a text, they are just sending an email to a specific number. Each cell carrier uses a different email address. For example, to send a text to an AT&T phone, you would send an email to, where x = the person's 10 digit phone number. Most of these services just use a lookup table to find out what email address to use with what phone number. Here a site listing all the addresses:

Its really simple to use PHP to send an email, just look around for tutorials online.
370  Community / Bar Sport / Re: The most important Arduino project ever. Please help. on: March 02, 2013, 01:19:15 pm
We don't have any gas lines in our house, but this make sense. Our home heating oil tank has a fail-safe shutoff, why wouldn't you have the same thing on a gas line? Maybe something like the hardwired smoke detectors that we have to put in apartments now, but instead of going to a call box, it goes to a gas shutoff valve?
371  Community / Bar Sport / Re: The pcDuino? on: March 02, 2013, 12:05:52 pm
It says its compatible with Arduino shields
Where to plug ??
=>  (Adapter Needed for Shield Form-Factor)

Written like this it is also compatible with 220V and 110V as there is only a adapter needed for the voltage...smiley-wink

Still it are these concepts that can move the world forward. Suppose every laptop and tablet would have a build-in Arduino with some extension slot that can be mapped upon shields or breadboards. Then I could experiment all day !

Apparently that group of 4 headers on the right side of the board are setup the same as the ones on an arduino (two headers for digital 0 - 13, one header for analog in, and one header for power distribution). Its not clear if the logic is 3.3v or 5v though. I would hope 5v, for it to be "Arduino compatible".

They have said that the adapter is just needed to give the correct spacing for the pins, so you could make your own with jumpers if you dont want to wait/pay.

I posted this here because I thought the board might have some sort of connection to Arduino, it seems that is not the case. Not sure how I feel about it using the 'duino name now.
372  Using Arduino / Project Guidance / Re: Arduino current maxes on: March 02, 2013, 02:38:52 am
Umm, you need between +7V and +12V, not -12V.

Thats probably just formatting. -12v 3A adapters are pretty rare from my (limited) experience.
373  Community / Bar Sport / The pcDuino? on: March 01, 2013, 08:24:02 pm

Saw this on the Sparkfun new product post. Searched for it here and got 1 unrelated hit.

Looks like an interesting product. It says its compatible with Arduino shields, and can be programmed using a simple Arduino-like interface.
374  Community / Bar Sport / Re: International Postage Rates (similar to "USPS out to kill hobby shipping") on: March 01, 2013, 01:31:57 am
P.S.  We rarely prosecute people for lying on gun forms in this country.

I highly doubt that. I "failed" a background check because I put "ME" instead of "Maine" on the form in the address field.

And they didn't prosecute you.  Did they?

And I wouldn't be surprised if I ended up on that list. The system is working as intended, 80,000 people were denied access to firearms because they had a criminal record, but checked the "I do not have a criminal record" box, right after putting in their full name, address, and SSN. We already lead the world in incarcerated persons per capita, how about we dont start jailing people for typos.
375  Community / Bar Sport / Re: International Postage Rates (similar to "USPS out to kill hobby shipping") on: February 28, 2013, 08:41:56 pm
I'm assuming subsidies are involved somewhere. Big companies get a preferred rate, and we get to pay for it. It always shocks people when they ask me ship a 15lb prop internationally, and I have to inform them that USPS shipping costs $70, UPS costs $150, and FedEx costs $190. Yet they can have a $30 Ikea chair mailed to them for free through amazon prime.

P.S.  We rarely prosecute people for lying on gun forms in this country.

I highly doubt that. I "failed" a background check because I put "ME" instead of "Maine" on the form in the address field.
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