by baddog1946 Sat Nov 24, 2012 8:21 pm
HI:
I think what you are looking for may be here.
Cheers!
Baddog
TRIODES - TUBE OPERATING PARAMETERS
Ib = Plate (P) current, in milliamps
Ik = Cathode (K) current, in milliamps
Ic1 = Grid (G) current, in milliamps
Eb = Plate to cathode potential (P to K), Volts
Ec1= Grid (G) to cathode potential (K), Volts
Ek = Cathode (K) to ground potential, Volts
Ef = Filament AC voltage (Volts AC rm
PENTODES - TUBE OPERATING PARAMETERS
Ib = Plate (P) current, in milliamps
Ik = Cathode (K) current, in milliamps
Ic1 = Control Grid (grid No. 1(G1)) current in milliamps
Ic2 = Screen (grid No. 2(G2)) current, in milliamps
Ic3 = Grid No. 3 (G3) current, in milliamps
Eb = Plate to cathode potential (P to K), Volts
Ec1 = Grid (grid No. 1) to cathode potential (G1 to K), Volts
Ec2 = Screen (grid No. 2) (G2) to cathode, Volts
Ec3 = Screen (grid No. 3) (G3) to cathode, Volts
Ek = Cathode (K) to ground potential, Volts
Ef = Filament AC voltage (rms)
STANDARD CIRCUIT PARAMETERS
Ebb = Plate supply voltage to ground (DC)
Eb = Voltage at the plate (DC)
Ec2 = Screen grid voltage (DC)
Esig = Input Signal voltage (RMS)
Eout = Output voltage to following grid (RMS)
Ec1 = Grid 1 to cathode voltage (DC)
Ec2 = Grid 2 to cathode voltage (DC)
Ec = Grid set bias (grounded cathode) voltage (DC). In the charts this is reported as the
grid to cathode voltage.
Ib = Plate current, (Ma-DC)
Ic1 = Grid 1 current (Ma-DC)
Ic2 = Grid 2 current (Ma-DC)
Rc2 = Screen dropping resistor (Meg-ohms)
Rcf = Grid resistor of following tube (Meg-ohms)
Rb = Plate load resistor (Meg-ohms)
Rk = Cathode resistor (Kilo-ohms)
Gain = The ratio of output signal voltage to input signal voltage.
%Dist = A value reported, but not defined as to how it was determined.
THE BASIC RELATIONSHIPS
TRIODES
Data on the characteristic behavior of triode vacuum tubes is in the form of a tetrad.
Plate-to-cathode voltage Eb or eb
Grid-to-cathode voltage Ec1 or Ec or ec
Plate current, Ib or ib
Grid current, Ic, Ic1 or ic
Grid current is rarely shown, except for those tubes where the application is in rf or if
frequency regions or in pulse applications.
The standard graphical plots show the relationship between a tube plate current and a
cathode to plate voltage for different grid to cathode voltages.
If we define grid current as positive when electrons are flowing out of the tube grid then
1) Ik = Ic + Ib (all in the same units)
Also the graphs show Ib on the left vertical axis and Eb on the horizontal axis with
reference to the cathode at ground potential. This is the only way to properly view the
characteristic curve plots.
PENTODES
Data on the characteristic behavior of vacuum tubes is in the form of a tetrad or pentrad.
Plate-to-cathode voltage (Eb)
Grid (G1)-to-cathode voltage (Ec1)
Grid (G2)-to-cathode voltage (Ec2)
μ is called the “amplification factor” or mu
rp is called the “plate resistance”
gm is called the “transconductance”
