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AlbinoFluttershy Featured By Owner Jun 14, 2016
Just around a week ago, I was at Pittsburgh Zoo. I figured that when I got to the Tropical Forest area, I would check out that sign...

Turns out that it was not on the wall that I thought it was on.

When I read the variable portion, I noticed that only two of the digits were mangled up. Also, the display was changing much faster than I remember (50x faster), and the changing digits were a lot louder than I remember. (Maybe I was working with the 4-inchers so much that I could hear the 1.5-inchers in the sign working.)
adamlhumphreys Featured By Owner Jun 18, 2016  Professional General Artist
I imagine they were pretty loud. :nod:

Also, I decided to do something a little less ambitious to start:
It's an animated marquee. :D
AlbinoFluttershy Featured By Owner Jun 18, 2016
The 1.5-inchers aren't all that loud when they change.

The marquee you made looks nice. I could possibly maybe get the schematic and try to copy it down for a larger marquee using more lights in the sequence.

I've actually planned out a different eggcrate digit build with pre-wired character set (1-2-3-4-5-6-7-8-9-0 and dollar sign).

I would make different sizes of eggcrate digits.
  • The smaller digits (for toll plazas, arcade games, etc.) would use bi-pin bulbs on a board and two rows of six pins in DIP format for connectivity.
  • Medium-sized digits (for clocks, outdoor signs, small scoreboards, studio applications, etc.) would use slightly larger bulbs (G4.5 up to S6) under a foam mask and use a six-by-two set of pins for connectivity.
  • Large digits (for clock towers, scoreboards, and advertising boards) would use special 6- or 12-volt bulbs in a grid and use a three-by-four female header for connectivity.

Since the digits would use a pre-wired character set styled like on Wheel of Fortune and The Price is Right, there would be no need for a special chipset to drive the display – just use a BCD-to-decimal decoder with an extra output for the dollar sign on the binary input "1010"!

And if you want a decimal point or colon separator, use light bulbs of the same type/voltage connected to a separate signal from the digits for each decimal point/colon separator in the display.
adamlhumphreys Featured By Owner Jun 20, 2016  Professional General Artist
Well, the schematic is just every pin on port A going to a 470ohm resistor and to two transistors, driving two bulbs at a time. That's really just about it apart form the buttons. ^^;

Sounds nice and simple to me! :la: Alternately you could use the CD74HC4067 and have up to 16 characters.

I have to say, it's a lot simpler than trying to scroll digits across a matrix. (Even scrolling a single byte was work enough. >_<) I have a clock in mind with fixed 3x5 digits. Maybe someday. :XD: I figure it'd be nicer and easier to read than a single digit 5x7 clock with too many settings. X3
AlbinoFluttershy Featured By Owner Jun 21, 2016
Okay, so I would just connect every pin on port A using a 470 ohm resistor and two transistors to drive two bulbs at once. (And I'm guessing the resistors would be used to prevent thermal shock...?)

How I would drive the digit would be to use a CMOS (5 or 12 volt) or TTL (5 volt only) BCD-to-decimal decoder IC for the inputs for pins 1 through 10 (the numerals). Pin 11 (the dollar sign) would use a separate signal, and would be triggered upon an input of binary "1010". "1011" through "1111" would blank the display.

Of course, I'll need help with setting up transistorized gates for the separate signal. Otherwise, it'll only show the numerals.

Some applications wouldn't need the dollar sign. Take the arcade game application, for example – the credit, score, jackpot, and ticket payout displays just show numeric data without any extra symbols.

If you want to get fancy with your eggcrate display, use a sheet of colored cellophane behind the lens to color the display. This would look especially appealing on an arcade game, for the jackpot display or the score display. Normal colors used on eggcrate displays are red, green, amber, yellow, and blue, but you can go fancier and use either purple or pink. (A smoke filter can be used to darken the display, or the filter can be omitted altogether for a normal white display.)
adamlhumphreys Featured By Owner Jun 25, 2016  Professional General Artist
Yup, and the transistors are in parallel pin to pin. No, the resistors are to limit how much current is being sucked from the driver (ATtiny84 in my case).

See, that's why that other chip would make things a lot easier, you'd already have 6 extra channels without additional circuits or soldering! :D

Maybe someday. Perhaps if I can find something that'll sell well that I can make fairly inexpensively. I developing a general purpose driver board ATM.
AlbinoFluttershy Featured By Owner Jun 25, 2016
Well, since RadioShack carries the the miniature bulbs I'm looking for (cat. no. 272-1154), I got myself four of those and two small PC boards (cat. no. 276-158).

I placed the four miniature bulbs on the board in a vertical line pattern across the center of one of the boards (columns L and M; and rows 9, 13, 17, and 21) and placed a few strips of tape over the bulbs to prevent them from falling off.
adamlhumphreys Featured By Owner Edited Jun 25, 2016  Professional General Artist
Yikes! :O I realize the connector is nice, but it's still an incandescent bulb. Unless you got them for dirt somewhere or can re-use the connector, for $2 more, you could've bought 100 bulbs: (Or 12 for $8.50: ^^' The layout on their PCBs is good, but the boards themselves are fairly brittle in my experience. Those are awfully cute bulbs to use though! :aww:

Awesome! :D
And yeah, keeping stuff on the board before soldering is always tricky. :nod:

Also, one 2N2222 transistor could probably drive 7 those bulbs in parallel without even breaking a sweat so-to-speak. :)
(1 Reply)
I am getting bored of all of the L.E.D. "NOW SERVING" signs that are used in supermarkets nowadays, so I'm planning on making some fancy signs that use eggcrate (EGx40) or vane (VNx4xx) digits. (They would be labeled under the ServTronics brand, which is a brand name that I stemmed off of ScoreTronics, which is funny, since I would be using ScoreTronics brand digits in the VN series signs.)


EGx40/VNx4xx: Eggcrate (EG), Vane (VN)
xx2xxx/xx3xxx: 00-99 (2), 000-999 (3)
xxx4xx: Four-Inch Digit Height
VNx40x/VNx45x: Five Vanes Form "6/9" (40), Six Vanes Form "6/9" (45)
VNx4xW/VNx4xY: White Vanes (W), Fluorescent Yellow Vanes (Y)

Which one do you want me to build as a prototype? Type the model number as follows:


The portions in (parentheses) are exclusive to VN series model numbers.
The portions in bold must be included in VN series model numbers.
adamlhumphreys Featured By Owner Mar 18, 2016  Professional General Artist
[EGx40][xx2.5xxx] :meow:
Or rather an eggcrate that supports 000-199 by just adding a column of bulbs (or full fixed numeral '1') to represent a 1 (kinda like a clock needs a separate '1' for only three hours for 12-hour format). Otherwise I'd think up to 99 should be fine. :)
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