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1  Using Arduino / General Electronics / Re: Bread Boards & wishful thinking? on: August 22, 2014, 10:57:04 pm
What would you ask of a Bread Board, other then 'better, tighter connections'?

 FTDI?
 USB in/out?

 What would be your dream development 'Bread Board'?

Much more area.  Like a table-top .... Oh yes, 6 contacts per strip, not 5, of course.

Other than the 6 contacts per strip, you could build this yourself out of the smaller boards.  The standard 830 contact boards have 3 wedges on one side and 3 cutouts on the other and you can stick them together.  Most come with an adhesive back too.  About 100 in a 10x10 matrix would be about table-top sized.  The rest of the features you can build to taste.

http://www.ebay.com/itm/830-Tie-Points-Rectangular-Adhesive-Back-Solderless-Prototype-Breadboard-MB-102-/181440287318

This guy has a mere 9 boards linked up:

http://www.nathandumont.com/files/images/vcf_ula.jpg

As far as I know, there is no entry at Guinness for World's Largest Electronics Breadboard so this is something you can attack if you want.
2  Using Arduino / General Electronics / Re: logic level for arduino pin 8 on: August 22, 2014, 10:41:19 pm
The 328P datasheet says VIL "Input Low Voltage, except XTAL1 and RESET pin" is 0.2VCC for VCC = 1.8V - 2.4V and 0.3VCC for VCC = 2.4V - 5.5V.  If you are running at 5.0V, then VIL  is 1.5V so it should be OK.  Did you test this with a multimeter?  Are you sure that signal is solid?  What does it look like on a scope?  Set a trigger level at 1.5V and see if it jumps up for some reason.
3  Using Arduino / General Electronics / Re: Lifespan of old NOS electrolytic capacitors. on: August 22, 2014, 10:33:40 pm
I'd recommend wearing eye protection while doing this, a faulty cap may burst, spraying corrosive electrolyte steam and aluminium shreds out.

Good thing I have home insurance!
4  Using Arduino / General Electronics / Re: Potentiometer vs Absolute Rotary Encoder on: August 22, 2014, 03:54:53 am
You could maybe combine one with a pot. Read the pot at startup to get a rough idea of where the wheel is then use the  incremental encoder from then on.

Maybe for certain applications that would work, but in my opinion it eliminates one of the best features of the encoder, which is that there is no limit to the number of turns that the encoder can make.
5  Using Arduino / Microcontrollers / Re: Replacing Arduino Due Chip (ATSAM3X8E) on: August 22, 2014, 02:53:49 am
First attempt went horribly wrong.  After cutting the pins, the pads are extremely sensitive and did peel right off.

Sorry to hear that.  ChipQuik works great for SMT devices.  I have used it for 144 pin devices and it works as advertised.  Hot air doesn't work well for many-pin SMT devices because it's almost impossible to get all the solder to melt at the same time.  If any of it is phase changing back into solidus, you usually take the pad off with it.

Skip to 10:20 for the important bits.



6  Using Arduino / General Electronics / Re: Lifespan of old NOS electrolytic capacitors. on: August 22, 2014, 01:48:03 am
Here is the data if anyone cares:

MALLORY
MADE IN U.S.A.   smiley-mr-green
TYPE CGS
130000 MFD 15VDC
POS +85C
MAX SURGE 20VDC
20-97563
235-7908B

the other one is the exact same but the last code is 235-7908A instead of B

I wonder if that last is a date code indicating 1979 vintage, which it feels like this could be.  They are still in beautiful cosmetically new condition.

Screw terminals.  Looks like quality.  Hope it works.
7  Using Arduino / General Electronics / Re: Lifespan of old NOS electrolytic capacitors. on: August 22, 2014, 01:38:00 am
Before you use them it is best to allow the capacitor's dielectric to reform. To do this connect each to a power supply through a 10K resistor and allow it to "charge" for 24 hours.

Cool, I will try that.  Now, for the dumbest question of my career as an electronics enthusiast, 10K on the positive terminal or negative terminal or it doesn't matter or both?
8  Using Arduino / General Electronics / Re: Potentiometer vs Absolute Rotary Encoder on: August 22, 2014, 12:56:26 am
Something like this?  http://www.ebay.com/itm/281346507599

Damn, that is beautiful.  I think I am in love.   :

Do they only depend on the A/D? Can I find "better" (e.g. more expensive) versions of pots that doesn't jitter and doesn't degrade (that fast) over time?

I just want to point one thing out.  I have an Tektronix 2465B 400MHz scope from the 80s, considered a very good scope in its day, and every rotary control (except one) is a pot.  It seems that all scopes from that period use pots.  I have a new model 2000 Agilent scope and every rotary control  is an encoder.  It seems that all scopes now, even cheap Rigols, use rotary encoders.  It requires no thinking to know there is a very good reason for this fact.
9  Using Arduino / General Electronics / Lifespan of old NOS electrolytic capacitors. on: August 22, 2014, 12:52:25 am
I have  a pair of giant 15V 130,000uF capacitors, each about the volume of a pint.  I have had these for about 30 years and can't even remember where I got them from, possibly a surplus store.  They are new, no oxidation or bulging or any obvious cosmetic problems.  Are caps like this good for anything?   Are they likely even good?  I will hook it up to my LCR meter, but I wondered what you all though.  What should I use them for?
10  Community / Bar Sport / Re: Overly expensive or ok? on: August 18, 2014, 02:36:37 am
I think I would go with 10 Uno 3 boards from Amazon

http://www.amazon.com/Arduino-UNO-board-DIP-ATmega328P/dp/B006H06TVG/

And a couple of these:

http://www.dx.com/p/arduno-37-in-1-sensor-module-kit-black-142834

You would be just as well off.
11  Community / Bar Sport / Re: Holy Crap Lightning Strike Damage! on: August 18, 2014, 02:29:37 am
I had a limb blown off a tree about 50' from my home office window one day while I was sitting there.  No way to lightning rod away that sort of issue.  Nature allows for supernovae, so I think we will just have to accept the danger of lightning too.
12  Community / Bar Sport / Re: [OT ITA] Lo spamm bar on: August 18, 2014, 02:25:19 am
197 pages?  What the hell is going on here?  I WANT IN!!  SOMEONE TEACH ME ITALIAN!!!!!!   smiley-grin
13  Using Arduino / LEDs and Multiplexing / Re: MAX7219 without scrolling on: August 18, 2014, 02:18:52 am
All I need is for it to display one or two numbers with two columns in between them.

Dumb question possibly, but why even bother with 8x8 LED matrices if you want to display a one or two digit number, unless your requirement is to use matrices because that would be "like totally rad, dude"?   Displaying a number like you indicate is an application for a 7-segment display.  If you want to do graphics, scrolling, alpha characters, characters in other languages, etc.  then matrices become relevant.  MAX7219s are wonderful for 7 segment displays also (common cathode variety only).

And I should mention I have added devices to projects before simply because they would be totally rad, so if that is what you want, go ahead.
14  Using Arduino / General Electronics / Re: Ampere meter with internal shunt resistor safe for 30A? on: August 14, 2014, 02:33:10 am
FYI. The listing says it is an internal shunt:

Measure current range of 0- 30A with SHUNT (internally installed) and accuracy of Class 2.5.

Not that I am saying I trust this particular seller or anything like that.
15  Using Arduino / Displays / Re: New "Bubble" display! on: August 12, 2014, 09:10:38 pm
Sparkfun bubble displays down to 1,727 that is -100 per day.

Rumor has it that Crossroads is trying to corner the market...   smiley-mr-green
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