This month I’ll be traveling to Maker Faires in Portland, Oregon, and New York City to sign and talk about my book, The Annotated Build It Yourself Science Laboratory. That, of course, is the new, updated version of Build-It-Yourself Science Laboratory, the classic 1960’s hands-on science book by Raymond E. Barrett.
The Portland Mini Maker Faire is being held September 12-13 at OMSI, the Oregon Museum of Science and Industry. I’ll be speaking on the Innovation stage at 11 AM on September 12. This is a bit of a homecoming for the book: Raymond Barrett was the Education Director at OMSI when he originally wrote the book.
Bonus: During O’Reilly’s Back to School sale (through September 17), you can get the E-book version of The Annotated Build It Yourself Science Laboratory for 50% off using discount code B2S5.
We found a remake from our project Make your own 1952 Fraction-of-an-inch Adding Machine on display at Xerocraft, a hackerspace in Tucson. They cut and engraved the calculator out of hardboard using their laser cutter. It’s sturdier than papercraft and it looks great!
Our two “dis-integrated circuit” kits are the Three Fives Discrete 555 Timer, and the XL741 Discrete Op-Amp. These two kits are functional, transistor-level replicas of the original NE555 and μA741 (respectively), which are two of the most popular integrated circuits of all time.
Last year, we wrote up a detailed educational supplement for the Three Fives kit, that works through its circuit diagram and discusses its principles of operation down to the transistor level. Today, we are doing the same for the XL741 kit, and releasing an educational supplement that explains how a ‘741 op-amp IC works internally, down to its bare transistors and resistors:
This ability to peek inside the circuit makes the XL741 a unique educational tool. In what follows, we’ll work through the circuit diagram, discuss the theory of operation of the ‘741 op-amp, and present some opportunities for experiments and further exploration.
You can download the supplement here: XL741 Principles of Operation (1.1 MB PDF)
- Get the XL741 kit at our store.
- Our original article here, announcing the XL741 kit
- Main XL741 documentation page at our documentation wiki
Spencer posted on our facebook page:
Thought you might enjoy this photo showing the WaterColorBot in action while inking some custom “brown bag lunches” for summer camp.
And here is another. Fun project!
They look great— thanks for sharing them with us!
The plums on our tree ripened all at once this year! Making this sweet and tart Lemon Plum Jam took care of some of the excess fruit in a tasty way.
- 4 cups plum pieces (pits removed, skin still on)
- 2 whole lemons—large meyers if you can get them—cut into pieces (seeds removed, peel still on)
- Juice of 2 more lemons
- 1/2 cup water
- 4 cups sugar
Heat the plum and lemon pieces, lemon juice and water in a pot on medium, stirring occasionally. After about 15-20 minutes, the fruit should be softening. Macerate the fruit in the pot—a potato masher works well for this. Add the sugar. Stir regularly and cook to the desired consistency. To test consistency, put a spoonful on a plate in the fridge. If it’s too runny after cooling for a few minutes, keep simmering and test again after a few minutes.
Makes about 2-3 pints.
Other fruit preserves from the Play with your food archives:
They posted a picture of the finished painting, which looks awesome.