Contour Enthusiasts Group Archives Forums Modifications Aesthetics Custom brake circuit

Hey, guys..

Yes, its legal.. As long as the brake light turns on as fast as normal, at D.O.T certified speeds, then its legal.. Once you remove the brake, who cares if it fades, or goes straight out, you aren't stopping, so its gonna go out, eventually anyway..

There is no effect to the light-up..

Actually, it isn't just a cap.. that would either cause no change (no ground path for the cap, so no light up..) or, if it were small enough, it would cause the light to fade on and off..



This is actually an op-amp controlled circuit, and the op-amp is a voltage follower, the output being the same as the voltage across a capacitor. Once the IC has a high, the transistor being fed by said IC saturates, turning the bulbs on instantly.

On power off, the cap discharges, slowly, through VR1 and a 10K, hence the output of the opamp decreases slowly, and thus decreasing the base current of Q1, producing a slowly fading bulb..


Key features of this are the fact that you can manually adjust the initial brightness of the brakes at power-on, and also adjust the timing of the fade-out, at any point.


I will host a schematic soon, and would be willing to make them, as well.. I also have circuits for brake flashing on power-on, etc, etc etc..


I'm an electronics technician in the US Navy. I am certified in Diagnosis, Troubleshooting, Repair, and Miniature/Micro-Miniature soldering (to 400x). Experience in Multilayer, flex-print, and SOP(Small Outline Package) components.

Anyway.. its whatever..


Ray

Ah, my bad. I'm still in the learning stages with electronics.

I'll wait for the schematics and see if i can decipher them.

Or clicky if no worky?? (I'm new to webshots)


Hope this works... if not, right click, copy and paste the location..


Ray

ok and i have no idea what u just said.

Ray, can you do this for the interior lights? Theater effect lighting when shutting the door.

I can, and will, make them... As I had already told another member, let me see the cheapest I can get components for, and I will throw a price together..

Give me until this evening, to research pricing (knowing how to do it, and readily carrying the supplies is a different story...)

If anyone would like a break-down of the operation of this circuit, I will paste it here:





The circuit can be explained as follows: When the car door is open, the push to off (PTO) switch of the door is ON and it charges the 22uF capacitor fully.
The opamp is acting as a voltage follower and its output is same as the voltage across the capacitor, which is 12V when the capacitor is fully charged. Due to a high voltage at the output of the IC, the transistor saturates, turning ON the bulb to full brightness, without delay.

Now, when the door is closed, the door switch is pushed in and hence the switch goes OFF. When the switch is OFF, the capacitor starts discharging slowly through VR1 and the 10K resistor and the voltage across it decreases slowly. Therefore the output of IC 741 also decreases gradually, decreasing the base current to the transistor. This produces a slowly decreasing current through the bulb and the bulb fades out and finally OFF, when the capacitor is fully discharged.

After building the circuit, with the PTO switch in ON position (not pushed in) i.e. the car door open(or brake pedal is depressed, adjust the preset VR2 to the required initial brightness of the bulb. Then push the switch in to turn it OFF(or close the door)(or release the brakes) and adjust VR1 for the time to bring the bulb from full brightness to OFF.

I would suggest you set VR1 and VR2 to their maximum values,
for theater lighting.


Just attach to your Brake circuit, instead, and viola!!!
You can bump up your 3055 transistor to one that will handle a higher current draw, in order to make it last a little longer, but mine has been running for 2+ years. Be sure to follow the setting procedure, in order to adjust the initial brightess, and delay..

(TOO long of a delay makes for poor notice to fellow drivers, in stop and go traffic... you let go and it doesn't fade much before you press it again, and they don't get that "flash" of "new" light, so their brain won't process it as having occured... OUCH....


Another note, these kits will come in small black plastic "project boxes", and will be of the utmost ease to install:

One end of the box will have a quick connect termination-style plug (speaker boxes, etc) and will be the input... the other side will have another of the same stile termination, and will be the output..

simply cut the brake lights positive wires, and run the LIGHT-BULB side of the wire to the "output" termination, and the other end of the cut wire (the one that leads to the brake switch) to the "input" termination, so that this box rides in between the two, ALA:

brake switch(or door switch) --- BOX INPUT --- CIRCUIT --- BOX OUTPUT --- brake lights (or dome lights)

I'll post this evening on a set price, and go from there..

Ray

Hey, i supply a lot of electronics, if you need anything, tell me. I order from a company in Hong Kong and they are very reliable and cheap.

damn i am excited!

Hey guys.. an update, as I promised..


As it stands now:
I have pricing on most items, and could probably build the circuit, as it is now... however, my own personal choice on this matter: I am going to have to redesign the circuit to incorporate a failsafe, incase the unit fails and you wouldn't have brake lights.. Product liability....

So... technically it would work, however the finished product would have to be different, so I could rest soundly at night... Take some time, and I will make sure to keep on top of this..


Any questions, let me know...


Ray