marmite (very f&f) 4g with high spec block

mercutio · Post by **mercutio** » Tue Oct 22, 2013 7:59 pm

would be easier to make a few up and flog them than to explain how we went wrong wheen you see us sitting at what used to be the kitchen table with the rest of the house smouldering around us

Post by **Thebusofwoe** » Tue Oct 22, 2013 9:15 pm

yea maybe we could persuade him

Im gna have a go, and if all turns out well, then maybe make a few for donations

Post by **Thebusofwoe** » Tue Oct 22, 2013 9:46 pm

Ok @rdprelude. I have redone the wiring diagram, does this look right?

Post by **Thebusofwoe** » Wed Oct 23, 2013 1:23 pm

Ah sweet ok. Will amend when i get home from work and repost pic just to be sure. Another thing, i cannot seem to find part TLC271IP. there seem to be other opAmp's but nothing that resembles that part you used.

Is there any other tips that you would recommend?

Cheers

Post by **Kemp** » Wed Oct 23, 2013 6:00 pm

Servus Rene,

here is another prelude(s) driver from frankfurt,germany

I needed nearly a whole day to connect the 2 vtec wires when i swapped in my h22a, and when i see what you have done in your prelude i feel pretty dumb ^^

<3 your tps meter

Post by **Thebusofwoe** » Wed Oct 23, 2013 6:46 pm

Hi chap. Is this the trace I have to restore with said diode?

Cheers

Post by **SPYDOR** » Thu Oct 24, 2013 1:06 am

Hi René, very impressive work you have accomplished and thanks for sharing it with us, although I can't claim to understand 90% of the electrical work!

You remind me of a guy I used to work with who started programming his own in-car computer with all sorts of information as soon as he started driving. 3 years later and he is now programming the ECUs for Formula 1 and NASCAR!

Are you planning on another car project once you sell the Prelude?

Post by **Thebusofwoe** » Thu Oct 24, 2013 1:20 pm

Wow,

what a history you have. All i can say is well done to you and your progress!! Very interesting read indeed. Well when you do sell the lude, don't be a stranger here chap. I think your knowledge is somewhat interesting and i would imagine that we would need it at some point

Thanks for the links chap. I was thinking about getting one of those kits to have a practise on at building circuit boards. I will get the bits together and have a crack. I will update my project thread as and when needed. Thanks again, and looking toward to seeing the MPG meter how to

K30DPC · Post by **K30DPC** » Sat Oct 26, 2013 7:07 pm

Great job Rene, but
1. eatch pair of your leds must have resistor - small value like 0.47Ohm. That's because leds doesn't have the same spec and this will reduce brightness differences.
2. if you connect 4 leds instead of 2 and then in parallel then you have to lose less voltage on resistors so they will have to be rated on with less wattage and make less heat.
3. Leds are very sensitive for voltage changes so they should be driven by instant current drivers. ATM your lights have different brightness when engine is running then when it's not

K30DPC · Post by **K30DPC** » Sun Oct 27, 2013 12:30 pm

rdprelude wrote:As for the 0.47Ohm resistor I'd disagree. Reason: When the LEDs are ON at full intensity their ON-resistance is 1.86V/26.3mA=71Ω each. You will agree that a serial resistance of 0.47Ω does absolutely nothing to it. Latter is two orders off to be of any current regulating significance.

Like I said this serial resistance is only for protection. You will agree that there isn't two exactly the same leds. Always there is some differencess between them. Even if very small under some circumstances it may damage leds. The way how you connect them is correct but not the best because current flowing thrue pairs doesn't have to be the same. I would call this budget way and personally if I was doing this kind of mod I go for this serial res and also use different leds.

Still I think it's very good idea and I'm happy you wanna show it on forum