Nuts & Volts - September 2006

www.americanmicrosemi.com/ products/search/

www.decodesystems.com/ old-ics.html

But seriously, they have all gone to PICs ... or their equivalent. For example, the MK151 clock kit sold by Ramsey and others uses a programmed PIC16C54C-04 micro-controller as its sole IC. So let me put up a challenge to our readers. Come up with a working PIC, Atmel, or Motorola microcontroller and I will see that it is made available to our readers — with compensation for your time, of course. For further details con-

tact me at TJBYERS@aol.com. Thanks!

DESIGN FOR OBSOLESCENCE

QI am looking for an Intersil ICM7260 Programmable 59 Timer/Counter. This is an older chip and I have tried several suppliers without luck. So I thought you may have a source.

— Jerry

AIntersil has been acquired by Maxim, and short of a bulk purchase from an obsolete semiconductor

jobber, the only place to buy this chip is from www.maxim-ic.com/parts. cfm/p/ICM7260. It appears this chip will be in production for the short term. But more and more, microcontrollers are taking over these chores. So be leery when using older ICs in a new design without first checking with the manufacturer to see how long they expect to make and support the product.

For example, as of this writing, Microsoft has pulled the plug on Windows 98 — a stable operating system used by many hobbyists. That means no more updates, no more bug fixes, and no more answers when things go wrong. The same applies to ICs that have run their course.

5V

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CLICK IS ONE, CLICK-CLICK IS TWO ...

QAt night, pilots can control runway lights at small airports by clicking their radio microphone. Seven clicks within five seconds turns on the bright lights. Five clicks is medium and three clicks is low. After 15 minutes, the lights turn off — an obvious way to save electricity. Well, I’m looking for a circuit that will let me control operations via the number of received clicks within five seconds. Ideally, the circuit would have a timer that once activated would shut off after a

COOL WEBSITES

Petals Around The Rose: They say the smarter you, the longer it takes to solve the puzzle. Rumor has it Bill Gates took one full week to solve it. Stupid me solved it in four moves.