This video is the repair and demonstration of an HP 410b Vacuum Tube Voltmeter. The demonstration shows the high frequency capability of the AC RMS voltage measurement.
Years ago, the shop I worked at, threw out a bunch of gear that was considered obsolete, among the stuff was an HP 410B and a HP 430C, and a bunch of other stuff. Needless to say, I picked it out of the trash, and took it home. I pull it out and use it when needed, especially to double check the output of some generators to make sure the attenuators are still good and calibrated. Just because somethings are old and need special care, doesn't mean they are obsolete and need to be tossed in the trash...
Nice meter and nice video. I picked one up at a local ham/radio gathering for $10. It was in excellent cosmetic condition and came with a manual. I had to clean the switches, replace 5 resistors, the filter cap and then replaced the 6X4. The OB2 tested new and the 2 12AU7s are a pair of RCAs that tested as new and very well matched on my Hickok. I was surprised he was selling it so cheap, it looked like he had just replaced the DC and resistance leads with Probe Master leads, so I figured it would have been a mess electronically. But it calibrated right up and was dead on with the meter. Excellent device!
@@leonardpeters3266 yeah, it’s crazy what people are paying for them. Though it’s considered one of the best VTVMs ever made and top quality HP devices are commanding top dollar. A friend’s grandfather is pretty much done with electronics so he gave me a bunch of tubes and tube gear and in one of the boxes was an RCA WV-98C VTVM and I’m starting to rebuild that meter as well. I actually just used the HP 410B about 20 minutes ago to do an alignment on a Philco 52-940 AA5 radio. Love that it has a 1 VAC range.
