Mine says 130ARB1/B7 but it seems to be a "house" number. I picked up this scope for $5 US and have been trying to fix it. My HV is to low (only about -900vdc) Found a shorted HV osc transistor and an open resistor. I also changed some HV caps. It's looking like it might be the flyback transformer. Trying to find one of those at the moment.