[R-390] Off topic Heath TC-1 Tube Tester

[Steve Hobensack]

Sorry for the off topic post, but there are some knowledgeable people here. The Heath TC-1 tube tester has a "set line" adjustment on
the meter scale that adjusts for the proper input voltage to the main power transformer. Sometimes when I insert a tube into the tube
socket, the filament voltage could drop as much as 0.5 volts should the tube have a heavy current draw. Does the test data roll chart  compensate for this? If I adjust the set-line pot and bring the voltage back up to normal, the needle (on testing a tube) will move out of the yellow zone (questionable) to the green zone (good). Sometimes I must move the set-line pot above the meter voltage centering line to achieve proper filament voltage.  
 
Steve N8YE