The Precise 9071 VTVM, Part 4: Continuing teardown, and replacing some parts.
Wednesday, October 21, 2026 at 09:16:04
This device is a complete mess, and everything needs to go. Since it’s all coming out, let’s pull the function switch and clean it. I started with a good deoxit dousing, and then a gentle brushing to loosen some of the crap. Then, into the bath it goes!
It came out decent enough.
After cleaning, it was sprayed with alcohol to displace the water, allowed to dry, then re-coated with cleaner and grease for the detents.
Next thing to do was pull the other pots.
These were just bad. I cleaned them and they still were difficult to turn - one was simply locked up.
The switch was reinstalled:
New pots were installed in the chassis. One is a 2MΩ pot, for some reason. The rest are “Those are totally real Bourns, Bro!” pots.
And, of course, just removing more of the snot-covered wire from the chassis.
Next up is the range switch, the pots on the face, and the rest of the wire. Stay tuned!
Next part of this series: Coming soon.
Previous part of this series: https://wereboar.com … tearing-down-a-unit/