Okay, so this is my first post here (other than the introduction post).
I ordered a Crix soundboard and a Jupiter Electronics lighting kit. I have a Canakit seven watt amplifier already so I’ll be using that.
The Jupiter Electronics kit that I got is great. It has the bar graph display lights in a count up/down pattern which switches to the firing pattern when the button is pressed. Pressing the button also flashes a white LED for the muzzle of the gun. There is the flashing white LED for the light next to the vent, a solid yellow LED for the other light on top, and a solid red LED for the SLO BLO. There is a pulsing light for the vent as well.
The kit also came with three DPDT switches. One wired up to turn the power on and off for the circuit. One wired up to turn the pulsing vent light on and off and one not wired up at all. The kit also came with clear, red, and orange LED covers for the LEDs.
I decided that I wanted to add to this kit a little just to personalize the end result a bit. First off there is the problem of getting the sound board to work using the SPST button included in the light kit. The light and sound boards require different voltages. There is a great tutorial describing how to wire them up using a DPDT button on this site. Unfortunately I don’t have a DPDT button nor does my local electronics store. Secondly I wanted to add two LEDs to the kit. I wanted to add an amber one for the hat light on the trigger ear and a white one under the front knob on the gun body. And finally I didn’t want just a flashing white LED when I pressed the button, I wanted red and blue LEDs to flash alternatively.
The usual disclaimers apply. This is for information purposes only. I can’t be responsible if you damage your stuff. So on and so forth.
I have a drawer full of electronics parts and found everything I needed to make this work. What I found in my electronics drawer is a five volt relay. Part number HE721C0500. Data sheet can be found here: http://www.hamlin.com/specsheets/HE700.pdf It is important that the part number has the “C” in it. Essentially this works just like a standard automotive relay but with five volts. The pin out is as follows:
1 is the normally closed contact.
2 is the relay coil activation positive.
6 is the relay coil activation negative.
7 and 8 are connected internally and are the common connection that is switched between the normally closed and normally open contacts.
9 isn’t used.
13 isn’t used
14 is the normally open contact.
When the coil is energized the connection from pins 7 and 8 to 1 is broken and a new connection from pins 7 and 8 to pin 14 is made.
So I will connect pin 1 to the sound board’s stream wind down input, pin 14 to the stream fire input, and pin 8 to the sound boards ground. That takes care of activating these sounds on the sound board.
Since pressing the button on the light board connects an input to ground I designed a simple circuit to drive the relay using a PNP transistor (part number 2N4403). Here is my circuit diagram:
The diode to the light board is there to ensure that the lights are only activated when the button is pressed and to ensure that the five volts driving the transistor doesn’t find its way to this input. The diode across the coil of the relay is a kickback diode and is there to protect the transistor. The five volts is taken from the regulated five volts of the light board. If you don’t know how to find this then you probably shouldn’t attempt any modifications to the board.
Next I wanted to add the alternating flashing lights. I used a NPN transistor (part number 2N4400) as an inverter with the output powered by the first transistor. This makes one LED come on when power is applied to the circuit by pushing the button. Using the output to the muzzle light from the light board to drive the other LED and the input to the inverting transistor causes the two LEDs to blink alternatively. Here is my complete circuit diagram:
Please note that I haven’t put the current limiting resistors for the LEDs in this diagram. These go in series with the LEDs and need to have their values calculated. If you don’t know how to calculate resistor values for the LEDs just do a Google search for “led calculator”.
Finally I just used the five volts and the ground that I brought out from the light board to power two LEDs (orange and white) for the two other lights that I wanted. Again these need to have current limiting resistors added.
Here is the circuit in its prototype stage:
The two LEDs on the left are the white and yellow (didn’t have orange/amber handy), and the two at the bottom are the red and blue. To the left of that is the output for the muzzle light (only using the white wire, the black is ground). The wire to the button (grey) that isn’t on the ground side of the button was cut. The grey wire on the far right goes to the light board and the other grey wire goes to the button.
When power is applied:
I tried to get a shot of each of the LEDs on, but my camera phone isn’t ideal for that. So here is a short video:
Because the output for the muzzle light doesn’t spend the same amount of time on as it does off when it is activated, one of the LEDs will be on for more time that then other. In my case it is the blue LED. In the video it doesn’t really look like it goes off at all, but it does (my camera phone isn’t that great). If I wanted the red LED to have the greater duty cycle I would just swap the two LEDs (and their current limiting resisters) in the circuit.
I hope that people find this useful, or at the very least interesting.
Cheers,
Kev