Hi All,
Quick two questions regarding a Hickok 539a tube tester I recently bought. Should I have the 60Hz "test signal" going to the grid without even pressing the P4 (test) button? I don't get any kind of meter reading(on the unit's meter) UNTIL I press P4 however I'm concerned about the presence of the grid signal without P4 being depressed. Also I find that when I plug the unit into my Sencore autotransformer (and don't use the built-in line adjustment) and set the line voltage to precisely 96 volts , I read the exact voltages (filament/heater , plate, bias) that I should have and the grid signal is spot on as well at 2.50vac, .500vac or .250vac (depending on what the range selector wswitch is set at) and I have no appreciable drop for most tubes when the P4 test button is depressed. Should I be looking for a bad resistor? Short in the winding of one of the two transformers or is this related as well to me having a "grid" signal present at the pins all the time? THANKS!
Quick two questions regarding a Hickok 539a tube tester I recently bought. Should I have the 60Hz "test signal" going to the grid without even pressing the P4 (test) button? I don't get any kind of meter reading(on the unit's meter) UNTIL I press P4 however I'm concerned about the presence of the grid signal without P4 being depressed. Also I find that when I plug the unit into my Sencore autotransformer (and don't use the built-in line adjustment) and set the line voltage to precisely 96 volts , I read the exact voltages (filament/heater , plate, bias) that I should have and the grid signal is spot on as well at 2.50vac, .500vac or .250vac (depending on what the range selector wswitch is set at) and I have no appreciable drop for most tubes when the P4 test button is depressed. Should I be looking for a bad resistor? Short in the winding of one of the two transformers or is this related as well to me having a "grid" signal present at the pins all the time? THANKS!
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RE Grid signal
If anyone is interested/reading this: So I did some further checking on my own and YES the grid signal should be present even without "P4" button (test button) pressed . BTW the line voltage meter is spot on as well so regarding 96v input (after line level rheostat) vs 100v as referenced on line voltage meter and in test manual, I can only assume there is a resistor that has lost some of its value therefore, setting the initial voltage at 96v compensates for this.
If anyone is interested/reading this: So I did some further checking on my own and YES the grid signal should be present even without "P4" button (test button) pressed . BTW the line voltage meter is spot on as well so regarding 96v input (after line level rheostat) vs 100v as referenced on line voltage meter and in test manual, I can only assume there is a resistor that has lost some of its value therefore, setting the initial voltage at 96v compensates for this.
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