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Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy

I completely forgot about noting the current on the low voltage windings! I added up the heater currents and arrived at the same 3.9A that you did. In addition to this, according to the data-sheet, the heater for the rectifier on the 5V winding takes 3A.

For the exercise, I also tried calculating the valve currents according to the cathode voltage and the cathode resistor. I did struggle to understand how to apply that for the 6R7 and the 6J5, but was able to do calculations for some of the other valves. The meter amplifier valve also puzzled me since the 95ohm resistor and 10V cathode voltage would suggest 100mA or thereabouts, but the data-sheet states that the maximum running current for the 6J7G is 2mA, so that didn’t make sense. For those that I was unsure of, I just used the value from data-sheet and arrived at somewhere around 150mA which is in a similar ball-park, although in all probability there are errors in my calculations. The values for first two 6K7’s were also curious as they come to approximately 12mA (8/700) which is more than the 10mA shown on the data-sheet. There is, of course, R1, the RF gain control in series, but one would presumably have to assume the highest case at minimum setting? It would seem that the valves can be pushed pretty hard at that setting.

I struggled a bit with the transformer screw positions but they seem to be placed 100mm (4 inches) apart on the long side and 77mm (3 inches) apart on the short side. Removing the transformer would allow me to make more precise measurements, but that will have to wait for another day or two until I am feeling well enough. I came down with some kind of bug a coulple of days ago.

Anyway, thank you for your help and for taking the time and trouble to confirm the calculations.

As a matter of curiosity, what catalog are you looking at please?