Rectifier Arc, Bad tube?? help

[Wayne]

That must be so you can...



...Nope! I give up. Why does the 5V have a CT?

W

[jjman]

That must be so you can...



...Nope! I give up. Why does the 5V have a CT?

W

I've read it's there so you can use it to tap for the power supply. Not sure if/why that's better than using one of the ends on the socket. Maybe it's easier on the winding.

[rfgordon]

NEVER ground the CT of the rectifier taps! Hammond really should tell you that with the transformer, but they don't. I had to learn that lesson the hard way, too!

What happens is that, since the HT output of the recto tube is on one of the filament pins, the HT goes to ground through the 5V secondary winding.

[Macshaft]

You should have heard the squeel at about 3 - 4 , oh my , the dogs were goin` nuts around here . Apparently , I had used a speaker cord (no Shield ) to plug in the LP and check her out . I spent about an hour poking around with a broken drum stick before I checked the cord . duhh . Sounds excellent now , even with some crap tubes .

[toneman]

whent through 2 -5u4's before I realised the CT was hooked up.

[rfgordon]

Circuit errors won't always be the cause of recto tubes dying violent deaths.

A while ago I had two brand new JJ 5AR4s go "fireworks in a bottle" when installed in a perfectly fine Pro Reverb. Haven't had the problem since, but with modern tubes, ya just never know.