How to power an LED

For those of you just starting with electronics, here is a quick explanation of how to power your LEDs, and why selecting the right resistor is so important.

Continue reading How to power an LED

Millisecond clock with a PIC

One of the first things I tried to do when I learned Assembly back in middle school was to make an ultra precise timer.  Much to my surprise this is very difficult!  Computer processors aren’t very good at keeping track of time.  The problem is that they’re always being interrupted (literally, so I guess this doesn’t count as a pun).  Even making a precise delay is difficult.  You can’t rely on the time it takes for a CPU to execute a certain number of commands because inevitably some other process will steal away precious clock cycles.

Enter the PIC microprocessor… Continue reading Millisecond clock with a PIC

Before you buy…

Harbor Freight is a great place to get inexpensive, hobby-grade tools, but it’s hit or miss.  If you’re ordering online it’s really tough to tell the quality of an item, and even in the store sometimes it’s not apparent how something will hold up.

Do yourself a favor and check out HFReviews before you buy.  If you’ve bought from HF before, do us a favor and write a review.

Oh and by the way…some people have given me that “look” when I say I shop at Harbor Freight.  It’s sort of a frustrated, disapproving sigh.  A reaction that seems to say, “You know better.  Why are you being a jerk?”  Well, there’s a mentality to buying from HF.  You have to be the type who wants to tear apart and rebuild everything as soon as you get it home.  Buying import tools is often like buying a “kit.”  It won’t work right out of the box, or even if it does you’ll want to make some adjustments.  I often like to fabricate extra pieces to enhance, reinforce, or modify my machines.  I wouldn’t do such a thing with an expensive industrial quality tool made in the USA, though in some cases modifications can make an import work even better than a domestic product.  It’s all about the effort you put in.  Here’s a good article that I came across.

McMaster-Carr…

…is an awesome company.  (but UPS is not)  If you haven’t heard of them before, go to www.mcmaster.com right now.

I ordered 3 R8 collets from them just before the holidays and UPS lost my package.  The tracking showed delivered to “front door” but it never made it to my apartment.   I sent an email to McMaster and within an hour they had shipped out a replacement order.  A few days later (Christmas eve) UPS showed it delivered, but yet again it was not at my apartment.  After pleading with UPS to help me figure out where my packages are going I gave up and called McMaster again.  Without any hassle at all they shipped out yet another order, this time with some delivery instructions for the driver.  I finally got my 3 collets.  My credit card was charged automatically for all three orders, but they posted credits for two of the orders within a few days.

I might have my stuff shipped to work now, but McMaster is always going to be my first choice supplier from now on.