Help with 6SL7 tube curves

Tube DIY Asylum

Do It Yourself (DIY) paradise for tube and SET project builders.

Very simple circuit below in one of my amps
B+ 370
Plate Resistor 220k
Plate Voltage 90
Cathode resistor 2.3K
Cathode Voltage 3.2v
Current 1.4mA (0.126 plate watts)
(Thats 100K after the 0.22uF coupling cap not 100 ohms)

So, looking at the tube curves, it does not look like this operating point should exist. With a -3v bias, the tube curve goes to zero current with 150 volts on the plate. What am I missing?
The amp plays fine. I got the ol' oscilloscope out and the tube makes a nice sine wave with 20 volts AC output from this stage.

Edits: 04/16/24

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Topic - Help with 6SL7 tube curves - Chip647 13:21:57 04/16/24 (6)

RE: Help with 6SL7 tube curves - Triode_Kingdom 13:51:50 04/16/24 (5)

You were right - Chip647 17:21:15 04/16/24 (4)

RE: You were right - Tre' 17:43:15 04/17/24 (2)

220,000 (nt) - Chip647 06:11:32 04/18/24 (1)

RE: 220,000 (nt) - Tre' 07:15:21 04/18/24 (0)

Glad it's fixed! - Triode_Kingdom 06:04:48 04/17/24 (0)

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