Hello. I’m in the learning process of meter repair and need help from you all. I too have a very nice 461-2 that has similar responses to the original post. I seem to get random numbers on the display. The volts in both AC and DC don’t respond to any input. All the resistance ranges display a 1 when either the leads are shorted or any resistance measured the display starts to show numbers that always count down to -000. I’m doing my tests with no batteries in the unit and running off the AC charger.
I’ve checked the basics like F1 and F2. I know very little about this type of logic. Based solely on the original post I jumped straight to ICL7107. According to what I see on the schematic I should have +5V between pin 1 and pin 21 of ICL7107 and I do. This is where I’m completely lost as I can see pins 30, 31 & 32 are Common, Input Hi & Input Low but don’t know how to test them and don’t want to smoke anything if possible. I have a logic probe if this is where I use it? I have used one once and that was 20 odd years ago.
Can somebody please point me in the proper direction to continue troubleshooting this meter? Any and all help is greatly appreciated. Thank you in advance for helping me struggle through this.
Robb