I have a Humirel 1101 sensor which measures relative humidity and has a linear humidity to frequency output. I want to change the frequency range (7350Hz @ 0%RH to 6030Hz @100% RH) to a linear voltage (0 - 1volt) to input to a chart recorder. Frequency DECREASES as humidity increases, but I want voltage to INCREASE with humidity, up to 1 volt. I have a 5volt supply, so the LM2917 won't work. Any ideas please? 555 timer as a F/V converter?