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Triode connected 6LW6 for SE

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As Tubelab/George has pointed out on several occasions, the 6LW6 is the big gun of sweep tubes, with a 40W plate dissipation. I have some of these in several flavors, and want to try them triode-connected as a stand-in for 300Bs. I have some 3K Hashimoto transformers coming that I want to try with these before springing for anything more expensive. I know that George has tried the 6LW6 in triode mode with a Simple SE, but does anyone have a real idea of their plate resistance triode connected?
 
I know that George has tried the 6LW6 in triode mode with a Simple SE

I never tried to measure the plate resistance, but it is pretty low. I was experimenting with cathode follower output stages and the 6LW6 will operate with the lowest voltage across the tube, in the order of 50 to 75 volts with cathode currents in the 200+ mA range. It even beat the usual triode voltage regulator tubes in this application. The circuit used the "augmented cathode follower" design so the voltage across the follower tube remained constant.

Beware there are several different constructions of 6LW6. They don't all work the same. There are versions without heat radiating fins welded to the plates and at least 3 different types with different fins. The biggest can dissipate 80+ watts with no glow.

The screen grid rating is 275 volts. Some tubes will work OK at 400 volts in triode, and some will run away at 350. Test carefully before leaving the amp unattended if pushing the envelope on voltage. A triode connected tube still looks like a pentode at idle.
 
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