- #1
Twm Sion
- 5
- 0
Hello
Please my apologies for mistakes as I am a new member, and I would like to ask a how to question,I am trying to make a system up that I can use on my racing cars ( classic hence no onboard computer )
What I want to do is to have a 12 volt pulse(from 12 volts to o volts) that I can use on my recording equipment to record my engine rpm. I have done it mechanically with a magnet and reed switch and it is successful up to 7000rpm ( taking it off a shaft ) but now I am trying to make one using a photo transistor with a reflected light as cannot use an interupted beam. I seem to have a system working of sorts but I am using a 5 volt supply with the phototransistor and my recording hardware will not recognise the +5volt to 0 volt range so what I would like is a system that will utilize the on off of the 5 volt to give me a 12 volt wave at up to 7000rpm, seems insurmountable to me but then I am old and decrepit !
any help gratfully received and if I can get it working correctly will send you a link to you tube to see it working
cheers Twm Sion
Please my apologies for mistakes as I am a new member, and I would like to ask a how to question,I am trying to make a system up that I can use on my racing cars ( classic hence no onboard computer )
What I want to do is to have a 12 volt pulse(from 12 volts to o volts) that I can use on my recording equipment to record my engine rpm. I have done it mechanically with a magnet and reed switch and it is successful up to 7000rpm ( taking it off a shaft ) but now I am trying to make one using a photo transistor with a reflected light as cannot use an interupted beam. I seem to have a system working of sorts but I am using a 5 volt supply with the phototransistor and my recording hardware will not recognise the +5volt to 0 volt range so what I would like is a system that will utilize the on off of the 5 volt to give me a 12 volt wave at up to 7000rpm, seems insurmountable to me but then I am old and decrepit !
any help gratfully received and if I can get it working correctly will send you a link to you tube to see it working
cheers Twm Sion