pulse relay needed

[96terrano]

I'm building a chime module for my truck because I hate the standard buzzer that tells u ya lights are left on, I know how to build the chime circuit, but I just need a relay that if I put 12v in the input, I get a 12 pulse on the output, does a thing like this even exist? Would a flasher relay work?

[rustic]

Originally Posted by 96terrano

I'm building a chime module for my truck because I hate the standard buzzer that tells u ya lights are left on, I know how to build the chime circuit, but I just need a relay that if I put 12v in the input, I get a 12 pulse on the output, does a thing like this even exist? Would a flasher relay work?

If you are building the chime circuit, then you could incorporate a NE555 timer, built as a monostable, this will give out one pulse after a single trigger input.
The width of the pulse depends on the component values. The current output would only be approx 200mA so you would need to trigger a relay, or a high power transistor.
Do a search 555 monostable and you will find loads of circuits.

Why do you need a pulsed output, what is it driving?

[arcascomp]

I know what you mean though, that nasty dying fly noise is a bit limp!

[96terrano]

Originally Posted by rustic

If you are building the chime circuit, then you could incorporate a NE555 timer, built as a monostable, this will give out one pulse after a single trigger input.
The width of the pulse depends on the component values. The current output would only be approx 200mA so you would need to trigger a relay, or a high power transistor.
Do a search 555 monostable and you will find loads of circuits.

Why do you need a pulsed output, what is it driving?

This is what I read on another forum I'm not sure how to wire the 555 timers, so what this guy done sounds easier.



I designed a simple chime circuit ~30 years ago to act as an
alarm on an intensive care nursing unit. If you place a large
electrolytic capacitor across a Sonalert piezo tone sounder,
and briefly pulse it, you get a rather pleasant decaying
chime tone. This is like the light/key alarm in some cars.
Some variations are attached. You can test the sounds with
just the Sonalert, a capacitor, and a battery.

[Lazy-Ferret]

Maplins do several led flasher kits, which can easily be adapted to do exactly what you want, provided the Chime is low current, you could just put the chime cct in place of the LED's. Saves having to mess around with the dreaded Veroboard.

The Indicator Flasher will not work, as they rely on the current being drawn by the bulbs to regulate the flash speed. Not enough current, and they flash really fast, and even less and they don't flash at all. You could look for one that is specifically for LED indicators I guess, but that is why the flashes stop working when you put the normal low current LED bulbs in, and you need to get ones with loading resistors for Indicators and CANBUS.

http://www.maplin.co.uk/leisure/elec...led-based-kits

If you wanted to be really different you could just do one of these instead of the chime...
http://www.maplin.co.uk/leisure/elec...its/sound-kits

I like the single message one, you could record a voice... "Oy idiot, you left your lights on.. Again..."

[96terrano]

Originally Posted by Lazy-Ferret

Maplins do several led flasher kits, which can easily be adapted to do exactly what you want, provided the Chime is low current, you could just put the chime cct in place of the LED's. Saves having to mess around with the dreaded Veroboard.

The Indicator Flasher will not work, as they rely on the current being drawn by the bulbs to regulate the flash speed. Not enough current, and they flash really fast, and even less and they don't flash at all. You could look for one that is specifically for LED indicators I guess, but that is why the flashes stop working when you put the normal low current LED bulbs in, and you need to get ones with loading resistors for Indicators and CANBUS.

http://www.maplin.co.uk/leisure/elec...led-based-kits

If you wanted to be really different you could just do one of these instead of the chime...
http://www.maplin.co.uk/leisure/elec...its/sound-kits

I like the single message one, you could record a voice... "Oy idiot, you left your lights on.. Again..."

Cheers, I also seen something I eBay, I'll get a link

[96terrano]

http://www.ebay.co.uk/itm/CSO7-Inter...0#ht_500wt_716


or


http://www.ebay.co.uk/itm/DEI-528T-1...#ht_2183wt_730

[Lazy-Ferret]

Originally Posted by 96terrano

http://www.ebay.co.uk/itm/CSO7-Inter...0#ht_500wt_716


or


http://www.ebay.co.uk/itm/DEI-528T-1...#ht_2183wt_730

I don't think the second one would be much good to you, as it is one that you trigger, and it then runs for that time, like an egg timer, you would use that for say a heated rear window, you push a button, and it then turns on for 15mins, and then turns off until you push the button again.

The first one is good, but quiet slow, on the minimum setting, you would get 1/2 second of noise, followed by 2 and a 1/2seconds of silence before it repeated. Although to be honest, if you know anything about electronics, it would be pretty easy to change out the 2 resisters for a slightly lower value, to speed it up a bit.

[rustic]

Originally Posted by Lazy-Ferret

I don't think the second one would be much good to you, as it is one that you trigger, and it then runs for that time, like an egg timer, you would use that for say a heated rear window, you push a button, and it then turns on for 15mins, and then turns off until you push the button again.

The first one is good, but quiet slow, on the minimum setting, you would get 1/2 second of noise, followed by 2 and a 1/2seconds of silence before it repeated. Although to be honest, if you know anything about electronics, it would be pretty easy to change out the 2 resisters for a slightly lower value, to speed it up a bit.

I agree, with the second item.
The first is probably based on the 555 timer anyway.

[(RIP) PLANK]

I think what you need is an astable multivibrator circuit, I remember playing at making these things for our own cars as an apprentice TV engineer back in the early 80's - night rider was all the rage and everyone wanted lights like KIT - very easy to make and a change or resistor or capacitor value alters the time of the pulse

http://en.wikipedia.org/wiki/Multivibrator

Google it and see what you come up with

[96terrano]

Originally Posted by PLANK

I think what you need is an astable multivibrator circuit, I remember playing at making these things for our own cars as an apprentice TV engineer back in the early 80's - night rider was all the rage and everyone wanted lights like KIT - very easy to make and a change or resistor or capacitor value alters the time of the pulse

http://en.wikipedia.org/wiki/Multivibrator

Google it and see what you come up with

i might put lights like kit on my T2

[96terrano]

Originally Posted by PLANK

I think what you need is an astable multivibrator circuit, I remember playing at making these things for our own cars as an apprentice TV engineer back in the early 80's - night rider was all the rage and everyone wanted lights like KIT - very easy to make and a change or resistor or capacitor value alters the time of the pulse

http://en.wikipedia.org/wiki/Multivibrator

Google it and see what you come up with

i'm trying to find something that i can basically plug the piezo beeper and capacitor into, i have no experience working with chips

[(RIP) PLANK]

Originally Posted by 96terrano

i'm trying to find something that i can basically plug the piezo beeper and capacitor into, i have no experience working with chips

you don't need chips just transistors, capacitors and resistors, all cost only pennies

[96terrano]

Originally Posted by PLANK

you don't need chips just transistors, capacitors and resistors, all cost only pennies

fair enough, i'll see what a need to make one, i can solder fine

[briggie]

dont even need transistors ......... make your own out of diodes like proper engineers used to lol