As I understand it, the OP wants to modify an existing circuit to allow only the fog lights to be lit when a "new" switch is installed.

Attached is one of the easiest ways to accomplish your "or" circuit.

All you need is a new switch, find the terminal on the relay coil that is grounded (0 V with respect to the chassis or battery negative) when the normal light switch is activated.

You would desolder that wire (or break it), solder the two diodes to the relay coil terminal or the wire leading to the relay coil terminal, and wire the original wire to one and the new switch wire to the other.

 

I understand what it is and how it works, but what I don't understand is what your assignment is. Are you trying to duplicate a preexisting circuit or design a new one from a standard set of parts, or something else altogether? You have an overabundance of parts for the job, but the way you stated the problem you have to use them all.

The key, like I said before, is using the capacitor as memory. Transistors and relays both make good logic modules, but the transistor can take a small charged/discharged capacitor and use it to control the rest of the circuit.

So what is the project, design something new, or breadboard an existing design, or something else?

Well the goal was to build the circut from the original diagram but i did not understand it..
but if it could be simplified and or duplicated a different way..
then thats fine

As I understand it, the OP wants to modify an existing circuit to allow only the fog lights to be lit when a "new" switch is installed.

Attached is one of the easiest ways to accomplish your "or" circuit.

All you need is a new switch, find the terminal on the relay coil that is grounded (0 V with respect to the chassis or battery negative) when the normal light switch is activated.

You would desolder that wire (or break it), solder the two diodes to the relay coil terminal or the wire leading to the relay coil terminal, and wire the original wire to one and the new switch wire to the other.

would this involve installing a seperat(new) fog light switch? i would like to keep the existing without adding another switch.. but all input is greatly appreciatted!!!

 

How many switch positions does the existing light switch have?

 

How many switch positions does the existing light switch have?

just 2 on/off

thats the reason for the circut to just add complete control.. when the headlights are not on.. the switch is seperate from the accual headlights switch..

 

If there are already two seperate switches, you can do the "or" function so you can have both the headlights and fog lights on ..... "or" ..... just the foglights on.

Of course, I may have the original problem statement incorrect.

 

If there are already two seperate switches, you can do the "or" function so you can have both the headlights and fog lights on ..... "or" ..... just the foglights on.

Of course, I may have the original problem statement incorrect.

that would basically be the purpose of the circut.. to have total control.. right now i can only turn them on and off when the headlights are on.. with the circut i will be able to turn them on and off anytime even if the headlights are on

 

So can you show us what you've done? I could build this sucker, but I'd like to look at yours first.

Why did you state you had to use both relays and the MOSFET?

 

So can you show us what you've done? I could build this sucker, but I'd like to look at yours first.

Why did you state you had to use both relays and the MOSFET?

well im basically going of someone elses plan and trying to figure it out this is the diaghram he made and im trying to understand it and doesnt make sence to me...
sure let me get some pics and upload them!

 

OK, I took the design off this thread and modified it...

http://www.electro-tech-online.com/general-electronics-chat/99815-556-timer-toggle-flip-flop-circuit.html

It has not been built before, but it should work.

 

Thinking about it, you could also use the transistor as the inverter.

 

wow since im not a symbol expert thats almost just as confusing.. u stated earlier you could biuld this.. if you could id gladly pay you for your time.. then maybe ship it to me just a thought if not a few questions

what is the huge triangle in the middle
and with the irf 510 there are 3 connectors that com off of it and i see you have 2 that both go to the ground but then also have the R3 1K resistor commin of what looks like the back im gconfused with this also..

Thanks

 

If this is a school assignment you need to learn the language. The 556 is a 14 pin DIP package, the 555 is a 8 pin DIP package. Details on DIP packages can be found here.

http://en.wikipedia.org/wiki/Dual_in-line_package



The online AAC book has a section on component symbols...

http://www.allaboutcircuits.com/vol_5/chpt_9/index.html



If you have a question about something specific we'll gladly try to help, but it looks like you are going to need a camera.



You can see how some of this relates in my project series.

The 555 Projects

I show exactly how to wire these projects up on these articles.



It is part of a larger volume in the AAC book, Volume VI - Experiments, found here.

http://www.allaboutcircuits.com/vol_6/index.html


Thing about electronics, there is no getting around reading.

 

hahah i can assure you this is no school assignment.. just me trying to make this for my car..
thanks i will read this and report back with any questions
and yea i cant find my cameras upload cable

 

Give us the source on relays, I can draw a easy to follow board to help you out. Something like this (done for another project)...

 

that would be awesome!! what do you mean the source on the relay the power? or the actual relay type? its a basic mini 12v relay.. and power is 12v coming in.. if either of those is what you mean..

 

Without a type number I can not know it's size, shape, or pinouts. Little things like that.

 

ok i understand..
its a sanyou R69R
says
12a 125vac
7a 250v~
28v--- solid line then - - - three seperate underneath
250v~
bottom says
SRD-S-112D
it has 5 pins one offset and 1 in each corner

 

Attached is the datasheet

 

Thank you.

Sweetness, you want to go with your original schematic, or one of mine? The only reason mine are any good is I reduce the parts count.

 

I would like to stick with the same parts so i dont have to go buy anything else so i guess just use the original schamatic.. thanks