View Single Post
  #8  
Old 07-11-2023, 12:27 PM
Electronic M's Avatar
Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 14,816
Quote:
Originally Posted by Alex KL-1 View Post
Yes, is possible. Some CRT have "hot" G2. Is good to be safe/sure.
Some time ago I also had only a 600V Fluke DMM, and I needed to measure +Boost on a TV (near 900V). I carefully ajusted a attenuator asing the 600V range (on manual range) using lower voltage and a relatively robust potentiometer. then, I sub it with a array of series 1kV rated resistors to achieve correct value, and measured perfectly on the 600V range (in that time, I only made a 2:1 att; eg. 900V reads 450V).
Nowadays I restored a tube MM, using HV resistor on voltage scale divider. Resulted limited only by switch, and I comfortably use it's own full 2kV scale without any trouble.
There's another way to measure 1KV on a 600V meter. Find a 400V B+ source measure it with respect to ground and record the number, then measure the 1KV point with respect to the 400V B+ then add that value to your recorded value to get the actual value of the 1KV source....I did this once on an early SS RCA I was fixing on site with limited tools at a friend's house. It worked great. I think in my case it was a 900V boost, a 350V B+ and a 600V meter, but the same principle applies if the TV has power supply rails that are a good fraction of boost.
__________________
Tom C.

Zenith: The quality stays in EVEN after the name falls off!
What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
Reply With Quote