Good heavens no. Just an image on the net.
Yeah, it is pretty cool thou. Eimac something or other?
jeff
Yeah, it is pretty cool thou. Eimac something or other?
jeff
With +600V on grid2, you should be able to get about 85 mA out on the plate at 0V on grid1. 4000 uMhos gm. So its a 6V6 that takes 50 Watts of heater power. A good driver stage for something else, like a Sweep tube.
Many RF Power Pentode's Plates were made for very high plate voltages, so that they could drive very high impedances of high Q resonant loads.
In some cases the loads were Pi filters, low capacitance first capacitor, air core inductor, and high capacitance second capacitor to match the 50 Ohm transmission line.
The problem is that audio output transformers are not normally made for such high voltages, are not very high impedance primaries, and certainly are not intended to be Hi Q resonant loads. The Hi Q resonant load does not work well with 20Hz to 20kHz signals.
If you want to experiment, you can power the 10V 5A filament.
Then ground the suppressor grid, and ground the plate.
Next, use the Screen grid as if it is a Plate (20 Watt maximum dissipation).
The 803 looks good, thoriated filaments glow nicely, and the filament makes a great 50 Watt space heater in the winter.
I did something similar when I used a 4-65A Tetrode. I grounded the plate; then used the Screen grid as if it was a Plate (10 Watts maximum dissipation).
Kind of silly, but it worked.
And, the tube is pretty, lights up, etc.
In some cases the loads were Pi filters, low capacitance first capacitor, air core inductor, and high capacitance second capacitor to match the 50 Ohm transmission line.
The problem is that audio output transformers are not normally made for such high voltages, are not very high impedance primaries, and certainly are not intended to be Hi Q resonant loads. The Hi Q resonant load does not work well with 20Hz to 20kHz signals.
If you want to experiment, you can power the 10V 5A filament.
Then ground the suppressor grid, and ground the plate.
Next, use the Screen grid as if it is a Plate (20 Watt maximum dissipation).
The 803 looks good, thoriated filaments glow nicely, and the filament makes a great 50 Watt space heater in the winter.
I did something similar when I used a 4-65A Tetrode. I grounded the plate; then used the Screen grid as if it was a Plate (10 Watts maximum dissipation).
Kind of silly, but it worked.
And, the tube is pretty, lights up, etc.
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