atkelar | Restoration Project #31 - Precision Instruments Model 98 VTVM (1/2) @atkelar | Uploaded January 2022 | Updated October 2024, 58 minutes ago.
Last summer, I found this old school vacuum tube voltmeter on ebay for a reasonable price. It was sold as "for parts" and the inside was shown in pictures, so I knew that it was a restoration project. Still, I had no idea just how much restoration it would be.
This video - part one of two - takes care of the probes and the case.
There is a total of three probes available for this meter: The regular stock probe, an active high frequency one and a high voltage one. I got the regular and the HF one; might look for the high voltage one too eventually, which should go up to 60kV... but that's not importat, now that I have thie meter itself in a decent shape again.
The probes were missing their tips and one of the current jacks had something stuck in them (post-video update: a bit of prodding confirmed the missing tip of the normal probe was indeed stuck in there)
Everything that could oxydize, was. And there was a weird gunk inside the probe. Bottom line: making new tips, replacing quite a bit of wiring and components is why it took so long to restore this little gem.
0:00 Intro - Presentation
2:34 Probes: Overview / HF-Probe Disassembly
4:28 Probe Polish
5:26 HF Probe Internals and Cable
7:07 Regular Probe Disassebmly / Switch / WTF is that Grime?!
8:50 Cable Replacement (for now)
9:32 Probe Tip "Extraction" / Probe Tip Overview
10:05 Probe Tip Turning
10:45 Nickle Plating
11:23 Probe Assembly
12:12 Probe Tips and Done!
12:44 Case: Hardware / Sanding / Blueing
13:30 Case: Lid Repair / Sadning
14:30 Case: Painting / Feet Replacement
15:42 Case: Inner Lining / Badge
16:18 Summary, Outtake
Music:
My Train's A Comin'
Unicorn Heads
(YouTube Audio Library)
You can support me on Ko-Fi: ko-fi.com/atkelar
Last summer, I found this old school vacuum tube voltmeter on ebay for a reasonable price. It was sold as "for parts" and the inside was shown in pictures, so I knew that it was a restoration project. Still, I had no idea just how much restoration it would be.
This video - part one of two - takes care of the probes and the case.
There is a total of three probes available for this meter: The regular stock probe, an active high frequency one and a high voltage one. I got the regular and the HF one; might look for the high voltage one too eventually, which should go up to 60kV... but that's not importat, now that I have thie meter itself in a decent shape again.
The probes were missing their tips and one of the current jacks had something stuck in them (post-video update: a bit of prodding confirmed the missing tip of the normal probe was indeed stuck in there)
Everything that could oxydize, was. And there was a weird gunk inside the probe. Bottom line: making new tips, replacing quite a bit of wiring and components is why it took so long to restore this little gem.
0:00 Intro - Presentation
2:34 Probes: Overview / HF-Probe Disassembly
4:28 Probe Polish
5:26 HF Probe Internals and Cable
7:07 Regular Probe Disassebmly / Switch / WTF is that Grime?!
8:50 Cable Replacement (for now)
9:32 Probe Tip "Extraction" / Probe Tip Overview
10:05 Probe Tip Turning
10:45 Nickle Plating
11:23 Probe Assembly
12:12 Probe Tips and Done!
12:44 Case: Hardware / Sanding / Blueing
13:30 Case: Lid Repair / Sadning
14:30 Case: Painting / Feet Replacement
15:42 Case: Inner Lining / Badge
16:18 Summary, Outtake
Music:
My Train's A Comin'
Unicorn Heads
(YouTube Audio Library)
You can support me on Ko-Fi: ko-fi.com/atkelar
