Headlamp Modifications - Part 2

electrokid · Post by **electrokid** » Tue Jul 20, 2010 1:36 pm

Looking into the wiper delay "I have it on good authority" - read "I've chatted to a couple of people and they think it might be"

it looks as though the built-in delay on the BX is integral with the wiper motor. I have a wiper switch to look at so I'll be able to confirm or not in a few days.

However - if it's in the motor itself it's not worth fiddling with - that area gets mighty wet and digging into the motor is bound to be a pain so my thoughts are about something external - a genuine add-on rather than a mod.

I've started the Mark 2 'web' style drawings - the first page really is at the 'fag packet' stage...

http://www.briandenmee.com/BX/BXHeadlamps.html

and you see I'm trying to explain the circuit operation for each section.

Since the WW delay (and probably a bunch of other stuff) has common elements with the Mark 2 headlamp I though I'd separate off some of the circuit descriptions and just put links in actual designs - for example the description of the LM317T regulator section is now much better described at ...

http://www.briandenmee.com/BX/ElectronicsSupply.html

Some folks have described some of my circuit design as "over the top" - I prefer "belt and braces". The electronics supply for the ICs in a car cct design could be as simple as a resistor and a cap - but there's just a chance that a voltage spike or other anomaly could pop the electronics. My aim is always for something that can be build, fitted . forgot and never needs attention - hence the additional complexity at times.

Post by **mat_fenwick** » Tue Jul 20, 2010 1:41 pm

Hmmm, are 3 blank posts just to stir up more suspense?

electrokid · Post by **electrokid** » Tue Jul 20, 2010 1:44 pm

Nope - that didn't work either - try this

http://www.briandenmee.com/BX/Post.html

electrokid · Post by **electrokid** » Tue Jul 20, 2010 1:48 pm

Hmmm, are 3 blank posts just to stir up more suspense?

Is that working

For some reason the text Ive written is just not appearing in the post - I've stuffed y post onto a web page and posted the link - that works but the [ url ] stuff isn't a link now - I can fix that but I'd rather se my post in the right place.

? ? dunno what's occurring !

electrokid · Post by **electrokid** » Tue Jul 20, 2010 1:53 pm

Ok let's try that again - removed characters and spaces that might have confused...

Looking into the wiper delay 'I have it on good authority' - read 'I've chatted to a couple of people and they think it

might be'

it looks as though the built-in delay on the BX is integral with the wiper motor. I have a wiper switch to

look at so I'll be able to confirm or not in a few days.

However - if it's in the motor itself it's not worth fiddling with - that area gets mighty wet and digging into the motor

is bound to be a pain so my thoughts are about something external - a genuine add-on rather than a mod.

I've started the Mark 2 'web' style drawings - the first page really is at the 'fag packet' stage...

http://www.briandenmee.com/BX/BXHeadlamps.html

and you see I'm trying to explain the circuit operation for each section.

Since the WW delay (and probably a bunch of other stuff) has common elements with the Mark 2 headlamp I though I'd separate

off some of the circuit descriptions and just put links in actual designs - for example the description of the LM317T

regulator section is now much better described at ...

http://www.briandenmee.com/BX/ElectronicsSupply.html

Some folks have described some of my circuit design as 'over the top' - I prefer 'belt and braces'. The electronics supply

for the ICs in a car cct design could be as simple as a resistor and a cap - but there's just a chance that a voltage spike

or other anomaly could pop the electronics. My aim is always for something that can be build, fitted . forgot and never

needs attention - hence the additional complexity at times.

electrokid · Post by **electrokid** » Tue Jul 20, 2010 1:55 pm

Phew - at last - apart from the double spacing (courtesy of Notepad which is where I stuffed it temporarily) that's what I wanted it to look like

Post by **mat_fenwick** » Tue Jul 20, 2010 2:06 pm

Excellent - it all seems to be working now! I'll read through the links when I have a bit more time.

electrokid wrote:The electronics supply for the ICs in a car cct design could be as simple as a resistor and a cap - but there's just a chance that a voltage spike or other anomaly could pop the electronics.

Yes - I can vouch for that!

Although we should know tomorrow whether the repairs to the LPG system ECU have been successful.

electrokid · Post by **electrokid** » Tue Jul 20, 2010 2:14 pm

If you got to read the post on my webpage link you'll see I used proper quotes instead of the single ' ones and there's a space between the end of the second link and the 'not url' marker - I removed the proper quotes and made them single ' quotes and removed the space at the end of the link - then it all started working ok.

Yes - I can vouch for that!

Yes - I do hope my designs should survive welding spikes

Hope the ECU fix is successful

electrokid · Post by **electrokid** » Wed Jul 21, 2010 11:14 am

Both pages were updated this morning with something a bit more decent. It strikes me that Mark 2 is a lot of electronics just to simulate dim-dip and it's probably best not to bother. The idea of using web pages as a design sketchpad is reasonable though - almost any circuit I produce will use the LM317T regulator so that page will remain useful.

Strangely, the ww delay cct will share much of the Mark 2 headlamp design ! Just a much lower frequency / different component values around the 555 timer.

Vanny · Post by **Vanny** » Wed Jul 21, 2010 2:58 pm

Two questions/requests,

I want wig wag head lights for use on track, how easy would it be to add this to the wiring mod?

I also want to do funky things with the rear lights on the car, currently they go through relays (tail and indicator) for towing a couple of badly wired trailers i didn't care to rewire. I've been toying with a Microchip PIC and wonder if you have any experience using them to drive high wattage bulbs?

edit
Also i have a very simple freeware circuit drawing package, i'll email it to you if i can still find the install file on my home computer

electrokid · Post by **electrokid** » Wed Jul 21, 2010 7:37 pm

I want wig wag head lights for use on track

How do you plan to see where you are going when you are on opposite lock ?

Seriously - this was tried on some rally cars and the opposite lock problem meant that at least you could clearly see the tree you were going to hit

how easy would it be to add this to the wiring mod

Not actually sure what you're trying to achieve ?

a couple of badly wired trailers i didn't care to rewire

Damn - I've only got one badly wired trailer

I've been toying with a Microchip PIC and wonder if you have any experience using them to drive high wattage bulbs

Should be able to drive a FET gate directly - but I'd be inclined to run the PIC on lower-than-rail volts and interface with a couple of FET stages. Although I've been on a PIC course at Microchip I still prefer to keep it as simple as poss.

Also i have a very simple freeware circuit drawing package

I have Easy-PC but still prefer pen and paper ! It's also more satisfying screwing up a bit of paper and throwing it in the bin when it's wrong

Vanny · Post by **Vanny** » Wed Jul 21, 2010 9:09 pm

Sorry, I didn't expect i would need to explicit.

Wig Wag head lights flash alternatively from side to side, and are the sort fitted to Police cars. I'm not thinking of competing on track but marshalling where making people VERY aware that you are behind them can often be rather useful. Typically your travelling too fast and most certainly don't need opposite lock.

electrokid · Post by **electrokid** » Wed Jul 21, 2010 11:13 pm

Wig Wag head lights flash alternatively from side to side, and are the sort fitted to Police cars.

A-ha - I picked up the wrong end of the bog brush there

I'm going to breadboard the 'main circuit' as in
http://www.briandenmee.com/BX/BXHeadlamps.html
anyway - a circuit that will provide wig-wag is 90% there so I'll breadboard that at the same time - no probs.

That particular configuration I developed for the 555 timer is very useful in that it can be set for 1:1 mark space ratio very easily - the 'on' and 'off' times are independently set which is not the case with configurations found in the application notes. R5 adjusts the 'off' time and R4 / VR1 sets the 'on' time. The output can drive a couple of relays - one for each headlamp - and a third drive to replace normal headlamp operation - simple ?

I presume we are talking about main beam for wig-wag ?

What would be the flash time ? Should it be adjustable ? If so over what range ?

Vanny · Post by **Vanny** » Wed Jul 21, 2010 11:43 pm

I'm thinking main beam, but i'm wondering about FOG's too?

The scientific answer to the flash rate is quite simple, the left one should be lit on 'Nah' and the right one lit on 'Nee'. The rate is simply Nee Nah Nee Nah Nee Nah (ha, and now you'll be doing that all night long!).

I guess a decade counter could be used connected to a resistor bank so it would be set at fast, medium and slow at the repeated press of a button? Then you have the problem of where to put the button. Though an adjustable POT might be easier? Its like GCSE electronics all over again.

electrokid · Post by **electrokid** » Thu Jul 22, 2010 9:42 am

I'm thinking main beam, but i'm wondering about FOG's too?

If it's at the same rate and in time with the headlamps that's very easy to add.

Nah Nee Nah (ha, and now you'll be doing that all night long!).

Fortunately I didn't get to read that until this morning

I guess a decade counter could be used connected to a resistor bank so it would be set at fast, medium and slow at the repeated press of a button? Then you have the problem of where to put the button. Though an adjustable POT might be easier? Its like GCSE electronics all over again.

Too complicated - even for me

If you look at my 'headlamps' page the first stage is the regulator which powers the second stage - the 555 timer. At the moment the output is shown driving a transistor - put a relay coil in the collector (with a catching diode across the coil) and that's about it ! Reasonably large value for C1 - adjust R5 for Nee and R4 / VR1 for Nah and it's done.

There's a few more bits to add to make wire-up more easy and to make sure that normal headlights are the default but that's all there is to it

To make it adjustable make both the resistor legs a fixed plus a variable and use a 2 gang pot for the variables so that they are both adjusted together. Perhaps arrange for a small current to go through the filaments when they are off so that they never completely cool off which will help with bulb life.

On the dash a couple of hi-bright blue LEDs - one for Nee and one for Nah - also run at much reduced brilliance for normal main beam.

When I breadboard it I'll do so with the thought of putting it in a box - what sort of timescale are you thinking about ?