Hickok 133A meter and AVO valve testers - UK Vintage Radio Repair and Restoration Discussion Forum

John_BS · 4th Jan 2019, 3:20 pm

I was recently gifted the meter-movement from what I presume was a multimeter dating from the 40's? I can't find anything on the web.

A couple of points:

1. Surely a good example of how not to lay out a meter movement?
2. I've never seen a dB scale referenced to 5mW and 500 ohms: where does that originate?
3. The FSD current is a tad less than 40uA (as expected), and with a series padding resistor removed, measures about 1k55. This would allow the movement to possibly be used to repair CT160's etc. (omit the 10k parallel R)

John

4th Jan 2019, 3:20 pm	#1
John_BS Octode Join Date: Dec 2008 Location: Wincanton, Somerset, UK. Posts: 1,784	Hickok 133A meter and AVO valve testers I was recently gifted the meter-movement from what I presume was a multimeter dating from the 40's? I can't find anything on the web. A couple of points: 1. Surely a good example of how not to lay out a meter movement? 2. I've never seen a dB scale referenced to 5mW and 500 ohms: where does that originate? 3. The FSD current is a tad less than 40uA (as expected), and with a series padding resistor removed, measures about 1k55. This would allow the movement to possibly be used to repair CT160's etc. (omit the 10k parallel R) John Attached Thumbnails