total newbie needs help

[s]

Hi all,
Got a bit of a problem that am hoping you can help me with...

I need a momentary switch, easy enough I hear you say, but due to the
nature I need it to be timed...

Quick background, it's for the electronic gearchange on motorbikes. An
excellent firm produces an electronic gearchange for disabled bikers.
Gearchange is done by hitting one of 2 switches.

The problem is if the button is held for longer than 500ms then the
changer just keeps going on and changing gears...

What am hoping to achieve is a circuit that can be put in-line, that
will only allow a single "pulse" for less than 500ms..

Hope you follow that and can help me out a bit..

TIA

sparks

 

[Bob Stephens]

On Wed, 10 Aug 2005 16:35:55 +0100, s wrote:

Hi all,
Got a bit of a problem that am hoping you can help me with...

I need a momentary switch, easy enough I hear you say, but due to the
nature I need it to be timed...

Quick background, it's for the electronic gearchange on motorbikes. An
excellent firm produces an electronic gearchange for disabled bikers.
Gearchange is done by hitting one of 2 switches.

The problem is if the button is held for longer than 500ms then the
changer just keeps going on and changing gears...

What am hoping to achieve is a circuit that can be put in-line, that
will only allow a single "pulse" for less than 500ms..

Hope you follow that and can help me out a bit..

TIA

sparks

Google for 'One shot'

Bob

 

[sparks]

ty... perfect

Bob Stephens wrote:

On Wed, 10 Aug 2005 16:35:55 +0100, s wrote:


Hi all,
Got a bit of a problem that am hoping you can help me with...

I need a momentary switch, easy enough I hear you say, but due to the
nature I need it to be timed...

Quick background, it's for the electronic gearchange on motorbikes. An
excellent firm produces an electronic gearchange for disabled bikers.
Gearchange is done by hitting one of 2 switches.

The problem is if the button is held for longer than 500ms then the
changer just keeps going on and changing gears...

What am hoping to achieve is a circuit that can be put in-line, that
will only allow a single "pulse" for less than 500ms..

Hope you follow that and can help me out a bit..

TIA

sparks


Google for 'One shot'

Bob

 

[Pooh Bear]

s wrote:

Hi all,
Got a bit of a problem that am hoping you can help me with...

I need a momentary switch, easy enough I hear you say, but due to the
nature I need it to be timed...

Quick background, it's for the electronic gearchange on motorbikes. An
excellent firm produces an electronic gearchange for disabled bikers.
Gearchange is done by hitting one of 2 switches.

The problem is if the button is held for longer than 500ms then the
changer just keeps going on and changing gears...

What am hoping to achieve is a circuit that can be put in-line, that
will only allow a single "pulse" for less than 500ms..

Hope you follow that and can help me out a bit..

LM555 monostable mode.

Graham

 

[Naveed]

"s" <s@s> wrote in message
news:42fa1edb$0$1213$ed2619ec@ptn-nntp-reader01.plus.net...

Hi all,
Got a bit of a problem that am hoping you can help me with...

I need a momentary switch, easy enough I hear you say, but due to the
nature I need it to be timed...

Quick background, it's for the electronic gearchange on motorbikes. An
excellent firm produces an electronic gearchange for disabled bikers.
Gearchange is done by hitting one of 2 switches.

The problem is if the button is held for longer than 500ms then the
changer just keeps going on and changing gears...

What am hoping to achieve is a circuit that can be put in-line, that
will only allow a single "pulse" for less than 500ms..

Hope you follow that and can help me out a bit..

TIA

sparks

If you don't know what your doing then you might want to think twice about
your project.

If your going to use this to move up gear or down gear using this device and
it produces a spike or some kind of noise, it could causes the gears to
shift down when your travelling at high speed, it might become abit
dangerous.

Naveed