I have a Motorola r-2001c service monitor. The oscilloscope has no sweep on the 100us, 10 us, and the 1us settings. After testing and working thought the schematics I have replace many IC's and still have no sweep. I have check the trigger circuit and have a trigger signal into the 14428, there is an output on pin six very faintdue to speed. there is no output on pin 10 or rather no square wave pulse. I have studied the manual and need new direction . Is there another circuit I have missed, I checked the time base and hold off.
Looking for assistance Alex firstname.lastname@example.org