Ampeg B-12-N........

[sluckey]

I still have a question about the Bias current.  Is this an acceptable range?

yes

[Jack_Hester]

That's even better news.  I'll take this one to the house and enjoy it a bit.  It'll go in sections, like I carried it out there.  Amp repair will be put on hold for a day, and then the Falcon goes back on the bench.  Think I'll re-flow the solder on the problem triode connections, and go from there.  Thanks again, to everyone's help.  It's been a fun repair.  Have a good one.

Jack

[xm52]

The measured voltages look all good to me.

It's nice when the all the hard work pays off. Congratulations!

[Jack_Hester]

09:15 hrs. - I'm going to make some comparisons with two other rectifier tubes installed.  That is, comparisons with my Ampeg script Sylvania 5U4GB. 

The first is a JJ GZ34S:

Line Voltage to PT: 124.8vAC

Pin 4 - 372.9vAC
Pin 6 - 372.6vAC
Pin 2/8 - 5.27vAC
Pin 8 - 454.8vDC

V4 - 62.41mA
V5 - 58.19mA
-------------------------------------

Now the Arcturus 5T4:

Line Voltage to PT: 124.8vAC

Pin 4 - 372.2vAC
Pin 6 - 372.3vAC
Pin 2/8 - 5.26vAC
Pin 8 - 436.2vDC

V4 - 60.15mA
V5 - 56.05mA
-------------------------------------

Now the readings from yesterday, using the Ampeg script Sylvania 5U4GB:

Line Voltage to PT: ??vAC

Pin 4 - 368.0vAC
Pin 6 - 367.9vAC
Pin 2/8 - 5.12vAC
Pin 8 - 425.5vDC

V4 - 58.97mA
V5 - 54.04mA

I'm putting the Ampeg script tube back in, for now.  My ears can't tell the difference with my guitar.  So, I'll leave it as-is, for now, and just be pleased that this amp no longer has to be shuffled around, and possibly be cannibalized, because it doesn't work. 

Anyway, can't think of anything else to do with it, so to the house it goes.

Jack