I'm building a VTVM based on a BK Precision model 177I'm..

I have a 50uamp meter from a kirby flyback tester.

I'm gutting the kirby it has a 6w6gta tube I'm not going to use the 6w6.

Using a 12sn7gt dual triode instead of a 12au7 so I can make use of the existing tube socket in the kirby.

and a string of resistors to get to 11meg ohms 1%


I'll read the control grid, screen grid and plate currents, and HV on the 15 volt scale only.

Only trouble I see is how does one protect the meter needle from bending?
If there is a plate current surge, a glitch resistor might save the rest of the electronics but if the VTVM gets hit with 150vdc on the 15vdc scale It will rap the needle a few times around the end post.

tyvm in advance
de n8zu