Power Amps
845B is a directly heated thoriated tungsten cathode triode, which can be used for A1 and AB1 power amplifiers.
Filament Heating
Voltage: 10V
If: 3.25 A
Final Rating
Anode voltage: 1250V
Anode dissipation power: 75W
Maximum signal output power: 150W
Maximum anode current: 120mA;
Interelectrode capacitance
Input capacitance: 6PF
Output capacitance: 4.5PF
Inter-circuit capacitance: 14.5 PF
Static parameters
Voltage: 1250V
Voltage: 200V
Current: 80 mA
On-resistance: 3mA/V
Sunshine duration: 1.7K
You: 5
Tempering: 3.4K
Peak voltage(V):69V
Output power: 15 W
Recommended working status (reference value)
Single tube A1 class amplification:
Voltage source ----- 1000 1000 1250 volts
-Ug--- 145 155 209V
RL-----6 9 16 K
Current value------90 65 52 mA
Transconductance -----3.1 - - mA/V
Peak voltage --- 110 148 V
Li------1.7 1.9 2.1 thousand
Pout----24 21 24 W
Push-pull AB1 type amplifier:
Ua----------------- 800 1000 1000 1250 V
-Ug---------------- 125 170 175 225 volts
Hysteresis------------------ 4.5 4.6 4.6 6.6 Open
Ia--------------------------------80 70 40 40 mA
Ug(pk)----------------177 240 - - V
Ia(mAx.sig)---------170 230 230 240 mA
40 75 75 115 W