[R-390] Off topic Heath TC-1 Tube Tester
Gary E Kaufman
gkaufman at the-planet.org
Sat Oct 13 08:49:43 EDT 2012
I don't have a TC-1 manual, but both the TC-2 and TC-3 tell you "Insert
the tube and re-set the SET LINE control if necessary."
- Gary KB1FBI
On 10/13/2012 8:25 AM, Steve Hobensack wrote:
> 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
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