Future of Electronics - Page 1
Forum section: electronics / general

author: Longhair
author_rank: Regular Contributor
timestamp: December 26, 2010, 04:00:23 pm
content: On theLive Show #7, Dave brought out his LED Clock that he did as about 12 (starts about 0:55:55).It would be real interesting to make the clock using the same schematic but using updated parts to make it smaller and more efficient.

author: Mr J
author_rank: Regular Contributor
timestamp: December 28, 2010, 05:29:27 am
content: I've made a bunch of these, works greathttp://www.rentron.com/clock-sch.htmhttp://www.rentron.com/at89c205.htmUses the 8051 clone and a DS1307 RTCI'm still looking for a good one that uses the arduino, 16X2 LCD and some sort of RTC.I've tried the arduino with the ds1307 but is a pain even with the library.

author: Mr J
author_rank: Regular Contributor
timestamp: December 28, 2010, 05:44:17 am
content: oh by the way if you still want to make dave's clock using the MM5314 you can still get them athttp://www.unicornelectronics.com/IC/5000.htmlI have about 50 or so in my stock. Sometimes they come up on ebay as well. From the rumour I hear about the MM5314 there are still alot of NOS in Asia and Russia. the datasheet can be found athttp://www.datasheetcatalog.com/datasheets_pdf/M/M/5/3/MM5314.shtml. Note: just be aware there not the most accurate, they sync off the 50/60 hz from the AC line. Here in the states after deregulation of the power companies, the line frequency can change, is not so tight with the 60 hz anymore like in years past.

author: williefleete
author_rank: Regular Contributor
timestamp: December 28, 2010, 02:08:37 pm
content: i've done a clock using two 8 pin PICAXE chips, a 74HC595, eight UCN5841's an old car clock ticker for a 1ppS timebase and 8 common anode LED displays with a few extra passives and buttons for time settingit will show the time to the second and keeps its time reasonably well plus i can use the serial from it to drive more of the display units for a synchronous clock plus it has hourly beep which passes through the serial controlling the remote displays. and a spinning widget which changes every second

author: Mr J
author_rank: Regular Contributor
timestamp: December 29, 2010, 05:20:45 am
content: Quote from: Mr J on December 28, 2010, 05:44:17 amjust measured my power overnight it varies from 59.95Hz to 64.00Hz. (used a fluke 87V)anyone else measure this, be interesting to see.

author: williefleete
author_rank: Regular Contributor
timestamp: December 29, 2010, 05:38:20 am
content: at one stage i did make a crude mains meter which measured our new zealand mains voltage and approximate frequency using a wall wart and a PICAXE it did actually measure reasonably accurately the frequency measurement differing by about 1Hz eg it was spot on 50 Hz increasing to 51 on the odd occasion but that could have been a measurement glitch with the count commandvoltage reading wasnt too accurate i dont think but picaxe ADCs will only detect 5mV per step and i dont think the 5% resistors help so that is to be expected

author: tyblu
author_rank: Frequent Contributor
timestamp: December 29, 2010, 11:40:02 am
content: I think have 10-bit ADCs, so ~5V/2^10 approx 5mV/step corresponding to 240V/5V*5mV approx 234 mV/step in your case.