Are you want to build kW amp, with enormous grid current of power tube/s/? 😳
6C33C filament requires 40-45W, the tube capable 350-600mA anode (or cathode) current (even 1.2A peek), but has relatively low anode voltage tolerance.
I'm not sure, that tube is a good choice for CF.
6C33C filament requires 40-45W, the tube capable 350-600mA anode (or cathode) current (even 1.2A peek), but has relatively low anode voltage tolerance.
I'm not sure, that tube is a good choice for CF.
I don't think so. Good CF require high mu tube. 6S33S has very low mu.
I always thought a CF requires high gm, not mu ...
... which 6s33s has plenty, 28 - 50 mA/V.
And isn't it often used in OTL where outputs are cathode followers in PP (both circlotron or inverted Futterman) ?
I think they mean it isn’t rated for a high plate voltage.
Attached is an excerpt from RDH4. There are shown what impact mu and gm have to gain and effective plate resistance of a cathode follower.
At Ua = 100 V and Ug = -20...-30 V, 6S33S has mu ~ 2.1 and gm ~28 mA/V ---> Rp ~ 80 ohms.