What converts frequency to voltage?
 

Hi,

what is the part that converts the signal from the transmission to a linear voltage? I would like to find a way to monitor a flyweel speed and run a Variable frequency drive. The VFD uses a 4-20 ma or 1-10 volt input.
Thanks

Re: What converts frequency to voltage?
 

Within the ECM there isn't anything that does that. It coverts the frequency directly to a MPH or RPM value.

For an external thing-a-ma-bobber look at the Nat-Semi LM2907/LM2917 chip. It is a freq to voltage converter. Great for stuff like converting the VSS to a linear voltage that can be displayed on a voltmeter (with the volts as a direct MPH reading).

RBob.

I have used the LM2907/2917 to convert the VSS signal to MPH and the DRP's to RPM voltages for datalogging wilt the LM-1 WB-O2. Works like a champ. Very handy device.

Hey, maybe this LM2907/2917 thing is what I'm looking for. I recently installed a 6-speed tranny in my other car. This tranny has a reverse lock out solenoid in it. I would like to tap into the VSS (99 Mustang) and when the MPH is anything less than 5 mph, it should supply 12v to this solenoid, which then opens up the solenoid. I would like to do this all via hardware, so I'm envisioning some sort of little black box with this LM2907/2917 thing inside. Can someone give me some info/pointers on how something like this might work and what components I would need?

I'm guessing what I would need to do is first establish what the voltage would be at 5 mph. Then from there, install some sort of circuitry in this little black box that would "flip a switch" thus supplying 12v to the solenoid. Any help would be appreciated!

Check this out. http://www.national.com/ds/LM/LM2907.pdf It has all the info you need, even some sample circuits.