New build startup issues

[Ron Worley]

Alright...

It's a bad tube... I checked bias V in Stby, and it was good on V5, but V4 was ~-1.5V... no wonder it was red plating..

Swapped them around, and the issue followed... so it's a tube that is either bad from the box or I toasted it... There's $25 out the window..

I have one other EL-34, another GT... it's a "6" rating, while the other is a "4".. will running them together be harmful on either a short-term or long term basis????

OK, I just read the stuff on the GT site.. this rating as little to do with idle current draw, etc. I have a Hickok tester, could I use it to tell if these two are OK together??? It does Transconductance testing, but that just tells you how solid the tube is for remaining life, right???

[Ron Worley]

I put the other tube I had in on Standby, and things are looking peachy..

Bias V (max neg) is V4: -37.3V; V5: -37.43

BTW, Voltage from the wall here is reading 124V... that explains the somewhat high B+.....

Standing by...

Oh yeah, thanks NG!!

[jjman]

I went thru the exact same experience with the bulb limiter the other day. It was dropping the 120v line to about 90v.