LED speedo & Tacho Needles

[supradupra.com]

I have added this thread as my last one has mysteriously vanished from the forum completely like many others & I keep being asked how this is done so, thought I'd put it back for information!

Basically I have been asked how I relit the needles on my dash, well - this is how!

The stock needles pull their light source from the green bulbs in the back of the cluster. This light is carried through light guides and projected into the needles lighting them up.

When you fit LED replacement bulbs this tends to pack up due to the way LEDs direct their light.

What I built to get over this was a tiny light module that fits behind the needles.



This is built using a fibre washer to mount the tiny surface mount LEDs to and solder them to a couple of small wire tails for connection.

This is no easy task - the picture below shows the LEDs size - thats a standard dress making pin next to it!




By opening up the hole behind the needles a tad I then fitted the light module inoto the guage workings.



This then screwed back together and provided a light sorse behind each needle.



The LEDs have the resistor mounted remotely to keep size down and run off of the ignition supply in the instrument cluster which means the needles always light up with ignition on which looks better IMO.

The orange paint just polishes off the needles, this then allows you to paint the rear side of them whatever colour you want them.

I also separated off the red line area by modifying the fascia light guide slightly and installing red LEDs behind in a separate compartment.

With the needle LED conversion it would also be possible to incorporate different colour LEDs to indicate a shift point or red line limit, the possibilities are endless really, just fiddly



So - thats how it's done - very fiddly but well worth it

Clock buttons got replaced at same time with clear ones which also illuminate.





so that's the trick.

[group a supra]

**** hot as always stuey

[Karma Supra]

I never got around to doing it on mine

[JSeaman]

As always, very bright and pretty

[Dino]

does this mean u been looking into how much stuff cost's lol look's brill pal

[mrroverrover]

Very good but too much agro for me cos I'm lazy

Now hows about a blue led clock? You managed that yet?

[Kai]

I'm assuming it'd also be possible to incorporate a shift light into this setup, like the TVR's had...get to a certain spot on the rev range and the needle flashes red for you to upshift at the best moment...

[steve.82]

Originally Posted by Kai

I'm assuming it'd also be possible to incorporate a shift light into this setup, like the TVR's had...get to a certain spot on the rev range and the needle flashes red for you to upshift at the best moment...

Can't be too hard... catch a signal off the ignitor perhaps and feed it to a circuit that switches over a certain frequency

[steve.82]

Been thinking about it... a very high order audio crossover circuit should do the trick.

Was thinking digital brick wall filter but that's over my head

[steve.82]

or.... LM2917 (freq-volt converter, just found on google) fed to a comparitor?

edit: might not even need an external comparitor?
http://www.farnell.com/datasheets/64278.pdf

[Kai]

Or just buy a shift light, strip it down, and wire the output to the LED to the tach

[steve.82]

Originally Posted by Kai

Or just buy a shift light, strip it down, and wire the output to the LED to the tach

BOOOOOOOOOOORING!!!

http://members.tripod.com/~foz11/DIY...al_speedo.html