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I have a DS-1302 RTC module but how to use it?
I recall Jon Chandler made a vu meter clock but what he used for timing?
Am planning on a clock that has no hands, just LEDs but precision would be nice.
Actually, the circuit boards need to be at an angle to avoid splits where the LEDs go. I would lay out the boards with the LEDs offset, like the first sketch. An offset of 13 degrees results in optimal LED placement.
THANKS, will ponder te idea of several boards but confussed about number of boards.
I will try out the FORMAT/ DISTRIBUTE function. Will save some work.
As for the current draw, the do-nut leds will run on 5v - 12v. Tayda part #A-4779
The multi boards not sure about.
What's to be confused about? 100mm × 100mm boards cost $5 for ten.
9 boards arranged in a square give you a square 300mm ×:300mm –:the boards will be trimmed (by the fab house) to give you a disk of 300mm diameter (almost 12").
Three boards must be laid out. The pie-shaped boards at the corner. Four identical boards. The ends of the plus sign. Four identical boards. And the board in the middle with the brain.
The boards with the LEDs will have resistors and LEDs only. I'll rough out a schematic when it's not the middle of the night.
The idea of a 300mm clock sounds interesting for sure with a slight twist and a revamped schematic
the clock face is the Seahawk'
am contemplating using short segments of the LED/Neon strips for most of the LEDs (need to see if the yellow LEDs 1206 pattern will glow through the paint"
some specs of the LEDs I have
the green donuts = 6.6mma @5v
33ma @11.5v
a blue LED/Neon segment (1) = 8.6ma @11.5v
have 2 blinking green LED/neon LEDs for the eyes to blink every second
the 2 digit display is tossed out
could go with a 2ft wide clock and paint the Seahawk on.
Use 22g wire to connect all the 12 LEDs up (hours).
yes I could use through-hole LEDs but I want the face as clean as possible.
looking at using only 6 pie-shaped boards maybe 9? if I want to not use 22g wire (makes a real rat nest (margarita sign)
the LED/neon contacts are 4mm ctr-ctr if I use them for all the minute segments.
You've missed a key point of my schematic which is going to make your life extremely difficult.
If you're going to drive the green LEDs directly, there are 60 red LEDs to be multiplexed, with either 7 or 8 red LEDs on each of the 8 boards.
Your schematic has 10 rows × 6 columns. That's not going to work in any logical way in the separate pcb concept. To make this work, each type of board (pie shaped or slice of bread shaped) must be exactly identical. What makes the most sense is to have 8 rows, which go to all of the boards × 8 columns, each of which goes to only one board. If this isn't clear, please disregard entirely my every mention of this idea.
I get your point. Going to make some changes for sure.
One big change is to use through-hole 3mm LEDs for the minutes and go with 5mm LEDs for the hours.
Too much diffusion wthe the LEDs mounted behind the 1/4 plexiglass and paint.
So please go back to my original schematic and mux the green LEDs along with the red. In this case, resistors must be used on each board. Why do I say that? Because you should plan on different resistor values for the red and green LEDs, and half the boards have 7 red and 2 green and the other half have 8 red and 1 green. This means one of LED lines sometimes drives a red LED and sometimes drives a green LED.
There seems to be a disconnect between what I'm saying and what you're doing. Please refer back to my original schematic if you're planning on using the nine board array. If you're not planning on that, do what you like.
If you are doing the nine board array, you have to arrange things so that all of pie-shaped boards are EXACTLY IDENTICALLY THE SAME and all of the slice-of-bread-shaped boards are EXACTLY IDENTICALLY THE SAME.
I strongly suggest and recommend that you multiplex ALL of the hour and minute LEDs. This is both to maintain symmetry in the boards and to have any chance of having the brightness levels of the LEDs about the same. With the minute LEDs multiplexed, each illuminated one is only one for ⅛ of the time. With the hour LEDs directly wired, when illuminated, they will be on 100% of the time. The brightness levels will be wildly different.
Yes, if you do what I suggest, you'll need 9 times more resistors as I have already explained. That will be a difference in cost of less than a buck. But it will work and look good.
I suggest you draw a separate schematic for each type of board, and see how the connections work.
not to concerned if the red (hour) lds are brighter. They only come on once per led per hour but will consider including the hour LEDs with the minute LEDs in the same Matrix.
As for pcboards I am enlarging the pic for 24 x 24 (9 sheets of paper taped together and using INFAVIEW to print each section. Then lay out 9 - 100 x 100mm sections to represent the PCB. on top of the taped together pattern.
This will be the 3rd. time I have done this on a project.
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