40 Ohm Rheostat Problem

[tube-a-lou]

Hi all,
Working on this Precision tube tester I have a problem with the open
adjustable Rheostat it's frozen can't turn it I tried everything no good. So
could I use different value resistors, I have to lower the voltage thru the
tubes going to the meter because when I test a tube it goes past 100 with
all tubes tried so I have to use different values to get that voltage metered
down to show 75% with a calibration tube I got, what do you guys think.

Thanks
Tube

 

[BinaryMike]

Allied Electronics still sells Ohmite rheostats from 7.5W to 1KW.

 

[tube-a-lou]

Thanks I'll check I need the small open type with exposed coil.

Tube