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Hi Stephen,

So you have -161 V at pins 3 of the output tubes, but hardly an output signal.
When there is no nearly short circuit somewhere in the output wiring this
means that the output tubes draw just a very small current during the most
positive voltage level at the grids, pins 2.
Ideally you measure the waveform of Vg1 versus Vk differentially with e.g. a
7A13 or a 7A22. You could also first obtain the waveform of Vg1 in AC. The
average is (should be) zero. Now measure the average of Vg1 with a DMM in DC
mode. Substract the DC Vk from this DC level and then add the observed AC
waveform of Vg1. What are the two levels of Vg1k?
With Vk = -161 V I expect some Ia = 50 mA per tube. In triode configuration of
the EL84 that nominally means Vg1k = -2.5 V (Philips graphs). In our
configuration even a more positive Vg1k.
R59 is really needed as pull-up resistor. Not open circuit?

Albert