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DIY timer project NEED HELP! Answered

I'm looking to get a timer like this made for a movie prop, but know nothing about electronics. Anyone insterested in making one for us? How much would you charge? Post a reply if interested!



. If all you want is some blinky lights, your link is overkill. You don't need to have a functioning keypad, alarm, etc. . A member of the cast/crew may have the skills to do it. Try placing a free ad in a local newspaper.

I think what mrshow wants is something that has that style of display and counts to zero. I would like to build something like that, but I currently don't really have the time or knowledge to do so. What kind of timeframe are we looking at here?

. Well, if you have the parts laying around, you might be able to do it in an evening. Depends on how fast you can learn. . It's been several decades since I've done anything like this, but I'd start with a 7-segment LED display and a cheap timer with a 7-segment display. You can probably find a chip that will buffer the signal from the timer and feed the 7-segment LED display. If not you should be able to build something with a handful of transistors/resistors/etc. Stuff it in a box with a battery and attach the keypad.

so say if I bought a cheap kitchen timer, de soldered their display and connected the proper pins for each number's segment would that work?

. You might want to try PMing LasVegas - he seems to know quite a bit about electronics.

. I'm not sure, but probably not. If the voltage and current specs are the same for the LCD and LED, it should work like that, but LEDs usually pull a lot more current and I don't think the voltages used are the same. A buffer (I think that's what it's called) should handle that. . If the parts are cheap enough, I'd try it and see what happens.

> I think what mrshow wants is something that has that style of display and counts to zero. . Precisely. Or at least that's the way I interpreted "movie prop." Guess I didn't word it very well. . In abstract, all he needs is a periodic pulse (eg, 555), a counter, and display - the keypad/etc is just for show. Using a controller to count works, but there are much simpler ways to do it.

I think I could figure it out fairly quickly, but I don't have the parts laying around... unless there was a way to do it with nand gates... hmmm. I won't be able to complete anything for a while, but an interesting idea-a homemade logic circuit. really easy way to do it is just take a stopwatch that goes up to the hundredths of a second and play that in reverse. But making a curcuit is much more fun.