[ARC5] T-19 Update

[Mark K3MSB]

Hi Guys --

I found a problem in my zener regulated oscillator circuit.  When I fixed
that, most voltages were much better:

Oscillator Tube:

Pin 1:  --
PIn 2:  12.1
Pin 3:  190
Pin 4:  190
Pin 5:  --
Pin 6:  --
Pin 7:  0
Pin 8:  0


Eye tube

Pin 1:  0
PIn 2:  23.5
Pin 3:  82   (still high)
Pin 4:  130
Pin 5:  0
Pin 6:  190
Pin 7:  12.2
Pin 8:  4.8  (still low)


PA tubes

The grids (pin 4) now go to -47V.

The screen grids, are still around 140V.

My B+ key down is 510V.  That's a bit low, but I'm only running 85V in on
the AC variac, and that gives me 550 B+ Key up which is my reference
point.

Thinking about this (dangerous for me.....), here's the screen circuit:

----B+  510V
  |                    R90
  |--------- 20K-----620 ----------------- G
                                         |
                  155      145V    |------ G

The 20K resistor is in my PS and is as per Dave Stinson's article.

510-155 / 20K = 17.75 mA   Delta V = 355
155 - 145 / 620 = 16.1 mA
510 / 20,620 = 24.7 mA

If I want the voltage at R90 to be 270V, then Delva V = 240

240 / R = 17 mA
R = 15K

Based upon previous threads,  I don't think changing  Dave's value to 15K
is the answer.

I did swap out all tubes with my T-22 and there was no difference

Still no power output, but now when turning the antenna coupling control
and listening to the signal on my Icom, the pitch changes as I change the
coupling control.

73 Mark K3MSB