Neat Digikey Stuff

It is painful ordering stuff, it always takes me a long time to put an order together. I want to make sure I don't forget something and I am always tempted to get interesting things. I have decided that I will get them and have resolved to put them into parts drawers so when I do get the hankering to try the particular thing I know where it is, generally.

I saw a LDT0-028K described in Physical Computing, it is a piezoelectric switch, if you mount it from it's leads it will act of like an accelerometer, it does require a zener diode so I ordered them also.

I got 2 arduino programmed ATmega 168s microprocessors, and did a look around for what other people have been doing.

One "standalone" breadboard arduino tutorial was here, they used a 7404 IC to do the serial communication with a PC, apparently it is a cheap way but doesn't work with all PCs since it doesn't do true serial voltages..

Another "standalone" arduino, schematic is pretty simple.

I have been really wanting a better oscilloscope, I considered the parallax usb but it just doesn't look like it would do the signal work I will need, though it would be a good "course" for me at my level of knowledge. I want something that I won't have to buy twice. I think I will have to hold off on that a bit while I do some more research.

I do want to get a parallax propeller starter board, and it just happens that they are on sale on the parallax.com site this weekend. I was comparing the differences between the educational kit and the starter kit and went with the starter kit that comes with the demo board because it had the output plugs for keyboard, video etc on it which is really cool, plus it was marked down more. I was briefly toying with the idea of buying both but gave that up thinking that if I really need to get another I would have to figure out how to use the base propeller chip which is only $12.95. So I did finally decide to order the Propeller Starter Kit, it was on sale for $69.99 which is great, since the discount did cover postage which was a whopping $19 +- to residential address. I pruned down the order, I was going to get a bunch of other little things but decided that I could hold off. I worked it down to the $14 range by having it shipped to my work address and by dropping the other components. I was not happy about the shipping costs.

I decided to compare the manuals for the kits and thought I would also be able to do the labs in the educational kit on the demo board. While looking at components I saw that they don't use the 7805 5v regulator but rather a LM2904 which is a Low Voltage Dropout, without going into specifics it seems that it is a better choice for certain applications, if not all. I found this page that gives comparisons between standard and low voltage dropout regulators.