Power tubes not drawing current

[redplater]

I'm building an Eiclone monoblock stereo. It's an El34 ultralinear amp. Strangest thing. The tubes are not drawing any current. I've got like 570 vdc on the plates and -75 on the grids. It's not bad tubes....I've substituted two pairs and the same results. The tubes are drawing like 1 ma of current. The plates should be about 90 volts less. I'm baffled!

Thanks!
David

 

[mctavish]

With the grids at -75v your tubes are in cutoff and cannot possibly pass much current at all. As you decrease the grids to closer to ~ -30v the tubes will start to conduct and your plate voltage will decrease due to the current draw. This amp is fixed bias?