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Discussion Starter · #21 ·
All things can be made to work is my philosophy. This one will just need a little experimentation to find the simplest solution which gives the best result.

Here is my circuit for the rear lights.



Here is the circuit for the front lights in a GT40.

(I suspect the rear lights are similar, perhaps the resistor value is > 1K. If someone can check this in a Mini I will amend accordingly, but we will use this for now)

I hate this Smart Draw cct diagram program, I can't get the lines straight, if anyone knows abetter one let me know.



My circuit is designed to work from 5v the Scalextric one from 12V and of course is only trying to simulate rear lights.

So the possibilities.

1) Just cut and join tracks on the circuit board to recreate my circuit. The value of the 4k7 resistor may need changing dependant on the efficiency of the Led's.

2) My circuit can probably be made to work with parallel Led,s. This may reduce the amount of cutting & joining needed.

A starting point for this approach would be to short out with a small piece of wire the two 1K resistors. Now connect
BK to point A
HL to point B via a 4K7 resistor
Gnd to point C

This will work but depending on the efficiency of the Led's they will probably be too bright. Adjust rear light brightness by changing the value of the 4K7 resistor.
Adjust the brightness of the brake lights by adding a resistor in series with the BK lead.

Hope this makes sense perhaps someone can give it a go and come up with some values.

Richard
 

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Discussion Starter · #22 ·
OK you know me. This is not the easiest option but for me is the most elegant and the way I would go.

Still based on the GT40 front light board. The Mini rear light board is bound to be different can someone post one up?



Here is the original board



Here is a PaintShop modified one.

So we reverse L1 to put it in series with L2
We shuffle R2 across & it becomes The rear light resistor ( needs to be changed to 4k7)

We use R1 as a Brake light adjust resistor, will need reducing in value or a short as in the original design.

P1 becomes the BK connection
HL goes to one end of the moved R2
The LH end of the original R2 becomes Gnd

Of course this may all be useless if the Mini rear light board is very different. I suspect something similar will be possible.
 

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QUOTE (RichG @ 23 Jun 2005, 21:12)OK you know me. This is not the easiest option but for me is the most elegant and the way I would go.

Still based on the GT40 front light board. The Mini rear light board is bound to be different can someone post one up?

Rich,
as requested, here is a pic of the mini rear light board - hope the clarity is OK.



Cheers, following this thread with interest.

Mike

I edited the picture to shrink it 'tvwino'. Please can you keep your pictures to 600 pixels wide so the rest of use don't need multiple linked monitors to see the picture? thanks!
 

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Hi Mike

Thanks for the picture. Just need to confirm where the tracks go,



Can you confirm that the tracks in Red are right.

In particular the connection to the - point.

The tracks in Blue are confusing me can you confirm that they do not connect to the Led's, and that I have got the Led tracks right.

Another Question. Is this a picture of a digital or analog mini? Wonder what happened to R1 & R2?

Richard
 

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QUOTE (RichG @ 23 Jun 2005, 22:01)Hi Mike

Thanks for the picture. Just need to confirm where the tracks go,


Can you confirm that the tracks in Red are right.

In particular the connection to the - point.

The tracks in Blue are confusing me can you confirm that they do not connect to the Led's, and that I have got the Led tracks right.

Richard
<{POST_SNAPBACK}>

Rich,
your assumptions on the track layout are spot on - although the reason you were confused and have outlined the blue tracks is that the light patches are actually the board, the dark patches are the tracks. So to answer your question, the blue doesn't go anywhere - your red tracks are spot on.
...and the resistors are 1K


N.B. side note to swissracer, and everyone who doesn't have a 50 inch widescreen monitor on their desk - sorry for the size of my picture, didn't think about pixels - just focused on getting it reduced to below 1MB from it's original size.
 

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Doh...

Ok that makes a lot more sense now, anyway assumptions were correct.


A series diode, then 1K to the Led fed from 12v either means the lights are very bright or very inefficient?

Analog or digi car?

Solutions 1 & 2 still hold. Will go and see if there is an "elegant" one.

Better go & edit my pictures.
 

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QUOTE (RichG @ 23 Jun 2005, 22:46)Doh...

Ok that makes a lot more sense now, anyway assumptions were correct.


A series diode, then 1K to the Led fed from 12v either means the lights are very bright or very inefficient?

Analog or digi car?
Solutions 1 & 2 still hold. Will go and see if there is an "elegant" one.
Better go & edit my pictures.

<{POST_SNAPBACK}>

Rich,
the car is a digital mini, but I have just opened up an old analog italian job version and the board is the same.
The lights seem bright enough.

Cheers

Mike
 

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Here is the equivilant of the "elegant" mod above, Note **** This has been changed since original post ***

This is not easy when you have not prototyped it first.



So we reverse D2 to put it in series with D1
Remove R4

We use R3 as a Brake light adjust resistor, will need reducing in value or a short as in the original design.

I have used a wire ended resistor for the new R4 as more people have these. Drill hole in board at top to secure lead and solder to HL .

Remove Red & black wires from + & -

+ Becomes the BK connection
HL goes to one end of the new R4
The top end of the original R4 becomes Gnd
- Not used

Please also bear in mind that 4k7 is probably the wrong value, this is a theoretical modification, needs someone to do it and experiment with values.

Since when have Minis been rear engine rear wheel drive?
 

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QUOTE (RichG @ 23 Jun 2005, 23:07)Since when have Minis been rear engine rear wheel drive?

<{POST_SNAPBACK}>

Since they got fed up with complaints from people who tried the front engine front wheel drive version from years ago... I have only seen 1, and it might not have been tuned, but it was pathetic.

I'm sure they could do this now - although i recall the negative comments on this forum about the then planned release of front engine Peugeot 307. IMHO, the 307 is great, with or without magnet - don't know what the critics were on about, but then I'm only a hobbyist, not an expert.

 

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good news...

Brake light conversion works on cars with a scalex rear light board too


I did my 307 on friday night.

I used Rich's circuit diagram as a guide - i shorted accross the 2 built-in resistors (100 each) on the light board.

then wired a 1k resistor in series with a diode to the positive connection on the board - other end went to bk.

also connected a 4k7 resistor to the + pad on the board, other end went to hl on the board.

then finally wired the ground to the ground pad on the controller board.

works great! although the brake lights may be a bit bright, however once youre actually driving the car, its ok, as the brakes only flicker on every noew and then.

i would have taken photos, but my powerbase blew up before i got my camera out


fanatstic work rich!
 

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Discussion Starter · #31 ·
Hi Guys

There are many ways to skin this cat. If the Brake or Rear lights are too bright, just add a resistor in series with the lead that feeds them.


It can probably be made to work with the Led's left in parallel. I would experiment, but have not got a car with the rear light board.

The key is simple get volts to the rear lights & increase it in brake mode.

Glad it works in practice.
 

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Discussion Starter · #33 ·
Hi H

That's good news. I was concerned that without the 1K series resistors that if the the Led's were poorly matched they would each have a different brightness. In practice they probably all come from the same batch and will be fine. Turning one Led round was always going to be a bit tricky so I think this will be the best solution.
 

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Here is something that you might like to try. As long as the Led brightness level is OK or too bright it can be made to work.



Remove the existing + & - wires to the board.

So no mods at all to the board, connect as shown.

If in Rear or Brake mode the Led's are too dim then this will not work. However if they are OK then we are done. If they are too bright in either mode then add a resistor in series with the appropriate lead.

Perhaps someone could try this & report back.
 

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Discussion Starter · #36 ·
No diode needed. It is using D3 on the board.

This method not tried yet so may not work. Problem is if Led's are too dim.

If Brake or rear lights are too bright put a resistor in series with either the HL or BK wire as appropriate.
 

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Thanks Rich - thought as much.

Have finally found time to do a GT40 and based on the success of that a Fly 512 Berlinetta and Lola T70.

I've dreamt of this for a long while! Now to find some headlamps for the Fly classics.

(ferrari is showing tails and lola the brake lights)

In doing so found the Fly cars had a previous RevC board and that BK HL were not marked - had to figure it out myself.

After doing it twice I ended up putting my diode & resistor straight onto the chip and then running leads from those. Made for less connections.

Have to say thanks again Rich, wouldnt have happened without you!

And secondly it still mystifies the hell outta me as to why Scalex would release cars with lights and not use the available circuitry(?)

Off to shop for nice little rectangular leds tomorrow, the Coda Lunga and the Porsche 917s are just begging to be treated.

cheers
 

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QUOTE (RichG @ 27 Jun 2005, 08:39)Here is something that you might like to try. As long as the Led brightness level is OK or too bright it can be made to work.



Remove the existing + & - wires to the board.

So no mods at all to the board, connect as shown.

If in Rear or Brake mode the Led's are too dim then this will not work. However if they are OK then we are done. If they are too bright in either mode then add a resistor in series with the appropriate lead.

Perhaps someone could try this & report back.
<{POST_SNAPBACK}>

Hi Rich;
I have tried this method and it works fine!
For some peoples' taste the Tail-light setting may be a little on the dim side ... But I think it is certainly a good differential between tails and brakes (works for me).

Also this method is much quicker (simpler) than the GT40 method (no diode or resistor needed), in my case I merely cut the pos + neg leads from the pickup shoes connection (this was an analog mini I converted), added a little length and connected them straight to the chip (HL and Neg). All I needed to do was then fabricate my brake lead (BK) and connect this to the bottom of the diode on the rear lighting board.

regards all
 

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Hi Rich

This is a great thread and as I'm building a resin Ferrari 550 Maranello for use on my SSD circuit it of course has to be lit up appropriately and wonder if you could help


What I need to know is the best solution for getting the following wired up (I'm sourcing from radipelectronics as suggested):

4 x LED Headlamps - thinking of the Kingbright White (55-1630) or Bright Water Clear (55-1475)

2 x Rear Lights - Kingbright 3mm Round Red (55-740) with clip in lens (55-1004), which will pad out the 3mm LED to the diameter of the rear light holes (4.5mm)

- These I am thinking will be wired to the guide but I have no idea what resistors would be needed.

2 x Brake Lights - same components as the Rear lights described above.

- wired to the SSD chip somehow but only on when "braking" so not combined with a rear light.

There is no existing boards or wiring so I'll need to put resistors in the two circuits I guess - any ideas which types/values would be appropriate?

Washout
 

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Discussion Starter · #40 ·
Hi Washout

As a starting point I would wire the Headlamps to the guide connected through a diode and then a single 1K resistor in series with each of the 4 led's.

The Brake lights wire to BK through a diode and the Rear lights to HL through a 4K7

So the front lights are the same as the Scaley GT40 except *4. The Rear & Brake lights are the same as my circuit except separated.

You could wire the Brake lights through a resistor instead of a diode. 470 ohms would be a good starting point.

Then just adjust the values of the resistors to get your desired brightness while not going outside the rating of the Led's or drawing more than 20mA from HL or BK.

Hope this makes sense?

Richard
 
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