Hello!
I have built this circuit:
http://www.jogis-roehrenbude.de/Leserbriefe/Anzeigeplatine/Anzeigeplatine.htm
The problem is, when there's no input signal to the circuit, then there are still lines on the tube.
The lines are a little bit longer than they:
http://www.jogis-roehrenbude.de/Leserbriefe/Anzeigeplatine/Fertig-Foto-EM87.jpg
What could be the problem? Could somebody help me?
I have built this circuit:
http://www.jogis-roehrenbude.de/Leserbriefe/Anzeigeplatine/Anzeigeplatine.htm
The problem is, when there's no input signal to the circuit, then there are still lines on the tube.
The lines are a little bit longer than they:
http://www.jogis-roehrenbude.de/Leserbriefe/Anzeigeplatine/Fertig-Foto-EM87.jpg
What could be the problem? Could somebody help me?
Hi Jane,
EC8010 is right Danko. They were only ever meant for rough signal indication. Good luck on your project! It will look really neat.
-Chris
I like that!Just my 0.2dB
EC8010 is right Danko. They were only ever meant for rough signal indication. Good luck on your project! It will look really neat.
-Chris
Thanks for everyones response!!
If I short the 1.2M resistor, then the signal doesn't get to the tube, so that's not a solution.
I tried to insert a trimm.pot between the cathode and the GND. But when I started to increase the trim.pot's resistance, then lines started to grow longer.
When I turn off the amplifier, the lines are getting longer, when the B+ is decreasing.
Maybe the B+ isn't high enough in my amplifier? Under steady state, when all the tubes are warmed up, the B+ is 320V.
If I short the 1.2M resistor, then the signal doesn't get to the tube, so that's not a solution.
I tried to insert a trimm.pot between the cathode and the GND. But when I started to increase the trim.pot's resistance, then lines started to grow longer.
When I turn off the amplifier, the lines are getting longer, when the B+ is decreasing.
Maybe the B+ isn't high enough in my amplifier? Under steady state, when all the tubes are warmed up, the B+ is 320V.
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