12-03-2012, 11:42 AM
Agree with Ron, the 6X5 is one of the most notorious of the bads, and is mentioned at least once a week on radio forums. Just can't stand much abuse, but runs for decades in test equipment and other light load applications.
But you do need to make sure filter caps and paper caps have been changed out and installed correctly. Diodes will somewhat raise the B+, so you might want to add a shunt resistor to tame it. One of the bolt on 25 watt types to dissipate heat to the chassis is usually a good and practical soloution. Value? More of an art than a science, but Mr. Ohm will get you in the ballpark. OK, 150 ohms or so, probably. Fuse the set if it has not been done already. Best.
But you do need to make sure filter caps and paper caps have been changed out and installed correctly. Diodes will somewhat raise the B+, so you might want to add a shunt resistor to tame it. One of the bolt on 25 watt types to dissipate heat to the chassis is usually a good and practical soloution. Value? More of an art than a science, but Mr. Ohm will get you in the ballpark. OK, 150 ohms or so, probably. Fuse the set if it has not been done already. Best.
