Hey all,
I’m building my second revision of a tube mic. The first go around it went perfectly but this build the plate voltage and cathode voltages are measuring way higher.
On the first build I got 68v at anode, .8v at cathode and .2 at the grid.
On this non working build I’m getting 118v at the plate, 16v at the cathode and 0v at the grid.
If I tap on the capsule electrode on body I’ll hear the tube open for a moment before it closes down. I’ll also heat it work for a moment in the process of the tube warming up.
I double checked the layout in kicad and nothing seemed to change.. not sure what’s up.
Tried with multiple tubes… all same results
Any ideas?
I’m building my second revision of a tube mic. The first go around it went perfectly but this build the plate voltage and cathode voltages are measuring way higher.
On the first build I got 68v at anode, .8v at cathode and .2 at the grid.
On this non working build I’m getting 118v at the plate, 16v at the cathode and 0v at the grid.
If I tap on the capsule electrode on body I’ll hear the tube open for a moment before it closes down. I’ll also heat it work for a moment in the process of the tube warming up.
I double checked the layout in kicad and nothing seemed to change.. not sure what’s up.
Tried with multiple tubes… all same results
Any ideas?
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