My Second Radialva Groom Restore

[Radio Fixer]

OK! got it wrong. What you need to do is to replace the 250 Ohm R12 with the the 300 Ohm field and then IMHO its a correct configuration. The negative bias will be higher but a potential divider across the field coil can be used to get this back to -7.8V where R11 would return to. I would guess two resistors of say 47K Ohms would be a reasonable start.

Gary