2W screen R's for EL34

[mhuss]

HIWATT amps used typical 1k/5w screen resistors on the 50 watt amps, but an odd arrangement for the 100 watt ones. There was a shared 470/10w screen resistor for all four screens, and each screen had an individual 100 ohm 1/2w resistor. I'm sure the 100s were in part to even out the screen current from tube to tube, but they also acted as fuses. I've often seen a bad tube and a single burned resistor to match.

[Chuck H]

I built an EL34 amp using high-ish voltages and even blew up a couple of tubes refining the circuit and finding a tube that could stand up to what might be expected of a REAL EL34. After running numbers I ended up with 3W for the 1k individual screen resistors. They held up fine in the acid test (crank it and play the $h!t out of it for an hour) and are still in the amp and being used by the owner.

470V on the plates and probably 460 ish on the screens. I don't have the amp with me to check actual numbers. But I can tell you that the 3W resistors held up fine when one of a pair of JJ's AND one of a pair of Sovteks blew their screens.