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Re: Estimating current usage

 by bigglez ¦  Tue Apr 07, 2009 11:14 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Estimating current usage ¦  Replies: 2 ¦  Views: 881

I'd like to come up with an estimate for battery lifetime of the end nodes. Is this as simple as taking all my components, adding up their current draw, and dividing the battery's rating (eg, 1000 mAh) by this number to find the number of hours I can run on a full charge? Or is the process more com...

 by bigglez ¦  Wed Apr 01, 2009 5:35 pm ¦  Forum: AVR Microcontrollers ¦  Topic: Another relay question ¦  Replies: 4 ¦  Views: 1451

I even know a guy that paid an electrician to replace a ceiling fan - and the job was so simple I thought paying someone to do it was a bit ridiculous. A former co-worker's neighbour would not agree. He installed a ceiling fan himself. The house caught fire. The investigation confirmed that the cau...

 by bigglez ¦  Wed Apr 01, 2009 5:23 pm ¦  Forum: AVR Microcontrollers ¦  Topic: AVR PWM Motor Control ¦  Replies: 16 ¦  Views: 5841

I'm looking for what you mean by clamping diode and can't seem to find anything online. Do you mean a diode between the micro and transistor? No. The clamping diode, which may also be called a back-EMF diode, catch diode , or even snubber diode, is in parallel with the load (motor). Alternatively i...

Re: Acquiring Time signal - GPS

 by bigglez ¦  Mon Mar 30, 2009 4:25 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Acquiring Time signal - GPS ¦  Replies: 12 ¦  Views: 2959

Cool, very similar to what I was thinking about. Is the hours:minutes separator in the first one 2 LEDs or a special vacuum tube of a "colon" The colon is two glass neon vacuum tubes, held in clear heat shrink tubing. The tubes are readily available as part number NE-2. Further, the colons operate ...

Re: Acquiring Time signal - GPS

 by bigglez ¦  Mon Mar 30, 2009 3:33 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Acquiring Time signal - GPS ¦  Replies: 12 ¦  Views: 2959

filmo wrote:Yep, some nixie tubes.
An example 4-digit Nixie tube clock and a 6-digit Minitron tube clock:
Image
Image
Image

 by bigglez ¦  Mon Mar 30, 2009 2:17 pm ¦  Forum: AVR Microcontrollers ¦  Topic: AVR PWM Motor Control ¦  Replies: 16 ¦  Views: 5841

davbeck wrote:I got it working with a transistor but I don't think it was the voltage increase but the fact that it wasn't being ground out on the low side of the PWM and breaking.
Sorry, can't follow your text. Can you
post a schematic of how you wired up your
motor and the transistor?

 by bigglez ¦  Mon Mar 30, 2009 2:15 pm ¦  Forum: AVR Microcontrollers ¦  Topic: AVR PWM Motor Control ¦  Replies: 16 ¦  Views: 5841

davbeck wrote:My point was I didn't know the specs of the motors I was trying because I they didn't come with a data sheet.
So use a DMM or VOM to measure the motor in your hands today.

Re: Acquiring Time signal - GPS

 by bigglez ¦  Mon Mar 30, 2009 2:01 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Acquiring Time signal - GPS ¦  Replies: 12 ¦  Views: 2959

I'm thinking of building a retro-vacuum tube display clock. Nixie tubes? Or, some of the lesser known tube technology from the cold war era? Thought it would be nice to have some sort of automatic time acquisition capabilities so I never have to set the clock. You have several choices depending upo...

Re: Voltage regulator questions.

 by bigglez ¦  Mon Mar 30, 2009 1:37 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Voltage regulator questions. ¦  Replies: 4 ¦  Views: 1449

In my device, i'm using a LM7805 voltage regulator to bring the 9v wall wart adapter down to a regulated 5v for my project. The 7805 is generating a bit of heat trying to dissipate that extra 4v (actually, i'm not sure if this is how it works... i'm pretty new to electronics). Almost right. The reg...

 by bigglez ¦  Mon Mar 30, 2009 1:21 pm ¦  Forum: AVR Microcontrollers ¦  Topic: AVR PWM Motor Control ¦  Replies: 16 ¦  Views: 5841

davbeck wrote:I tried a few motors I salvaged. The key is that it will run on the output pin just not when I try PWM on even 90%.
Nope. The key is this:

What size motor? (voltage and stall current?)

Third request!

You have not provided enough basic facts to help you!

 by bigglez ¦  Mon Mar 30, 2009 1:18 pm ¦  Forum: SparkFun Product Questions ¦  Topic: Which switch do I need? ¦  Replies: 21 ¦  Views: 4053

I would expect one of the wires in each of the pairs to be ground. or perhaps +V but definitely a common wire among all three pairs. It just feels like you are making it harder than it is. I noticed that too. Problem is that many newbies are so focused on the outcome (making their project work) the...

 by bigglez ¦  Mon Mar 30, 2009 1:11 pm ¦  Forum: SparkFun Product Questions ¦  Topic: What's the easy way for mass soldering LEDs? ¦  Replies: 23 ¦  Views: 5011

I guess I'm having trouble understanding what the problem is. ... All this talk about solder pots and farming out for wave soldering is only necessary if you're doing a large volume of them since the setup charges for a handful of boards will overwhelm the actual assembly cost by far. Rereading the...

 by bigglez ¦  Sun Mar 29, 2009 1:21 pm ¦  Forum: AVR Microcontrollers ¦  Topic: AVR PWM Motor Control ¦  Replies: 16 ¦  Views: 5841

davbeck wrote:I have it connected directly to the microcontroller. Do I need to put a diode in between so it doesn't break and just coasts?
What size motor? (voltage and stall current?)

Until we know this data there is no way to know if you
can direct connect it to an AVR IO pin.

 by bigglez ¦  Sun Mar 29, 2009 1:19 pm ¦  Forum: SparkFun Product Questions ¦  Topic: What's the easy way for mass soldering LEDs? ¦  Replies: 23 ¦  Views: 5011

Here's something I thought, someone with more experience please correct me if that wont work. Apply solder paste on the holes/pads on solder side of the pcb. Place all the leds through the holes, there will be enough solder paste around the leads. Flip the board (place something over the leads so t...

Re: AVR PWM Motor Control

 by bigglez ¦  Sat Mar 28, 2009 8:47 am ¦  Forum: AVR Microcontrollers ¦  Topic: AVR PWM Motor Control ¦  Replies: 16 ¦  Views: 5841

davbeck wrote:How do I control the speed of a motor (not servo, not stepper) with the ATMega168? When I try to use PWM like I do to dim an led, the motor locks up and emits a high pitched noise.
What size motor? (voltage and stall current) Is the motor
Connected directly to the uC pins?

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