448VDC on the plate of a 6V6 (using a 6X5 rectifier tube)

7/30/2000 1:02 AM

DanF

448VDC on the plate of a 6V6 (using a 6X5 rectifier tube) I desperately need advice on a Rickenbacker M-88 (Champ size) amp that uses a 6X5 rectifier tube.     The amp has a 6X5 rectifier, 6SL7 preamp and 6V6 power tube. The power transformer is putting 325VAC on each plate of the rectifier. I’m reading 448VDC coming out of the rectifier tube and going to the first filter cap and to the plate of the 6V6.     Is this normal for a 6X5? The 448VDC output seems extremely high and will quickly burn up the 6V6, right? I’m perplexed because, although I don't have a schematic for it, the amp seemed un-modified when I got it. I tried replacing the 6X5 with a NOS tube – still got 448VDC (readings taken with the 6X5 tube in place and the other tubes removed).     I replaced all caps and checked all resistors. Before I got the amp the output transformer had experienced a meltdown, but I replaced it. If it helps I can send a schematic (pdf format) to anyone willing to offer any advice. I cross-posted this question 'cause I’m running low on ideas. Thanks – DanF