When driving the GM70's grid, this grid voltage may come above the cathode voltage in loud passages every now and than.
When that's the case, the grid will behave like a second anode and starts sourcing up to milli-Amperes of current.
This can easily be noticed when simulating the GM70 tube, but you can't see where it becomes fatal in a simulation.
So, my question is:
How far can you go in mA's grid current without damaging the tube, when overdriving the GM70's grid above its cathode voltage.
Hans
When that's the case, the grid will behave like a second anode and starts sourcing up to milli-Amperes of current.
This can easily be noticed when simulating the GM70 tube, but you can't see where it becomes fatal in a simulation.
So, my question is:
How far can you go in mA's grid current without damaging the tube, when overdriving the GM70's grid above its cathode voltage.
Hans
Last page of GM-70 datasheet.
Read this too.
p.s.
As you can see, even 100mA grid current is feasible (at +120Vp).
This assumes that previous stage has even 8W driving capacity.
Read this too.
p.s.
As you can see, even 100mA grid current is feasible (at +120Vp).
This assumes that previous stage has even 8W driving capacity.
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