How do you check tps voltage on 94 5.7 Chevy pu?

Best is with a scope, with it you can see if there are any "dead spots", happens with high mileage older cars. You should see a smooth wave, like at valve lift profile, when moved from closed-open and back to closed. Voltage readings should be around .75v closed and 4.5v open. Is there a dead spot, you would see the voltage drop in a certain spot, it is caused from wear on the contacts from driving at a certain pedal position over a long time.