Hi Bill, Before you go digital consider a retro solution -- use two loops of 1/4 inch tape (as in magnetic recording tape, or even dymo label tape). Put a tension pulley on one end and a small stepper drive on the other. Step at the appropriate rotation rate to create the desired snail's pace linear velocity. You can imprint numbers or just a color line on the tape. Sort of like a strip-chart flip-clock.
If you use LEDs it might be easier to use a collection of LED bars (as in the .1x10 in DIP package). Google for LED bar graph. For driving, look at the MAX7219 if you want far fewer wires (and your eyes can tolerate multiplexed LED's). Finally, see http://www.primeled.com/ /tvb ----- Original Message ----- From: "Bill Hawkins" <b...@iaxs.net> To: "'Discussion of precise time and frequency measurement'" <time-nuts@febo.com> Sent: Monday, April 01, 2013 3:06 PM Subject: [time-nuts] Time shown as two horizontal bars > Looking for a long, thin horizontal clock display for use above or below > a flat screen TV. > > Tried searching for "bar clock" and got a lot of useless hits. > > What I'd like is a display that is about half an inch (12 mm) high by > 12-18 inches long (30-50 cm) that is just two rows of 60 or 120 leds. > One row is labeled 0 to 59 (or 60) and the other is labeled 0 to 12. The > display does not stay at 12 or 60 but jumps back to zero. Power line > frequency is an adequate reference, as long as it always has the same > 86,400 seconds per day, except for added leap seconds. There should not > be a clock frequency adjustment. > > 60 seconds worth of line cycles bumps the minute bar (30 if it has 120 > leds), and 5 minutes bumps the hour bar (150 seconds for 120 leds). > > The clock is set (after startup and power outages) by four buttons on > the back - minutes, increment, decrement, hours. > > Have any of you connoisseurs of time seen such a clock? How about a bar > of leds that could be used to make a clock? > > Bill Hawkins > > P.S. Currently re-reading Terry Pratchett's "Thief of Time" - a whole > new way to look at time in a funny and perceptive story. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
