Yet another launch control. With bright LED's, clear Cliplite holders, & Piezo beeper

[georgegassaway]

FWIW - A small launch control I recently made for someone (blue tape is covering their name and NAR #).

Super-bright LED's (using a dropping resistor) with CLEAR Cliplite holders from All Electronics to scatter the light for better viewing angles. By being clear, it is obvious when they are lit because either red or green is seen if lit, if still clear (with no color) then they are not lit. Otherwise , if the Cliplite holders were translucent red or green plastic, on a sunny day it would not be easy to know for sure if the LED's were lit up or the sun was illuminating them (for similar reasons, the LED's themselves are water-clear).

Also a Piezo Beeper is driven in series by a blinking LED to make it beep for continuity. I've used that blinking LED method for many years, super easy way to get a beep-beep-beep (the blinking LED itself is hidden inside, can't hold a candle to the super-bright water clear LED's).

18 second Youtube video here:

https://www.youtube.com/watch?v=JF8WmMLUuto

To keep the continuity current low (10 mA), the two green LED's, plus piezo beeper, are driven by a transistor that is activated when there is continuity (using a 1000 ohm resistor to drop the current going to the transistor). So, the actual current thru the ignitor is 10 mA, and goes to the transistor with the 1k resistor. The transistor then powers, in parallel, the green LED's and Piezo beeper/Blinking LED.

It works on 12V. Power source will usually be 3-cell Li-Poly batteries (11.1 V), from 2200 to 4000 mAh capacity.

I know that a 1/4" Phono plug is not good for carrying a lot of current. But they will mainly be using this for Solar Ignitors and Q2G2 ignitors, not clusters. I have seen problems with RCA connectors used as Safety keys, mainly the chassis jack coming loose, causing it to lose electrical contact inside. I've often used actual key switches, but for various reasons, did not for this.

- George Gassaway

 

[cvanc]

Looks really nice. How do you make the faceplates?

 

[georgegassaway]

For the Faceplate, I used a drawing program to create the pattern for the hole locations and text. I cloned it to put several copies onto one piece of paper, to have extras in case of a mistake in applying the laminating film.

Printed the page out on an inkjet printer. But I know from past experience that inkjet ink fades badly in the sunlight

Went to Office Depot, and had it printed onto 24 pound bright yellow paper. The black Toner lasts a lot better than inkjet ink.

Cut out and used one of them as a guide for drilling holes into the top plate..

Then when it was time to apply it, I used .002" thick laminating film, about 1/4" or so extending from the top and bottom, and with a lot of excess along the sides so the excess could be folded inside the top plate.

The one thing I didn't like is that the 1/4" of laminating film extending past the paper is a bit shorter than ideal. Ought to be at least 3/8". But there was not room to extend it much farther without involving the screw holes. If I did it all over again I'd move the launch button up a little, and lights down a little, and move the text, to make the faceplate less tall and get extra room for the laminating film overlap.

Also a different enclosure might make it more practical to run the laminating film completely around the top and bottom too. But that was a nice enclosure that was big enough for the job with being too big (or too tall).

One trick I did for another controller was to use a piece of .04" thick plastic to mount the printed paper onto. It had 90 degree corners, not rounded. The laminating film covered it entirely and was folded underneath. Four small holes were drilled near the corners of the plastic, and also into the launch control. Then 2-56 (maybe #1 size) screws were used to secure the plate on place onto the panel. Now of course some of the electronic parts mounted into the holes would hold the plate on, I did that before. But, the corners warped up over time. Therefore, using little screws to keep the corners held down.

Below is a pic of that one, a two-pad control. Same kind of bright LED's and clear Cliplite housings. It also used a peizo beeper driven by a flashing LED, but in that case for arming, not continuity.

- George Gassaway