07-11-2013, 09:28 AM
Glad you found the problem, as something like that can really drive you crazy.
It still seems that at 207 V your B+ voltage is a bit low. Are you applying full AC line voltage? What is the bias voltage generated across the 325 Ohm wirewound resistor? If everything is wired correctly, you might try another 80 rectifier tube.
Getting the B+ supply up to 250 V or so will make a noticeable improvement in performance.
It still seems that at 207 V your B+ voltage is a bit low. Are you applying full AC line voltage? What is the bias voltage generated across the 325 Ohm wirewound resistor? If everything is wired correctly, you might try another 80 rectifier tube.
Getting the B+ supply up to 250 V or so will make a noticeable improvement in performance.