Single ended amplifier. The shield of the input jack is grounded. The center goes to the top of a 100 k ohm pot. The other end of the pot is grounded. The wiper of the pot goes through a 1 k ohm resistor to the grid of a triode, V 1 eh. The cathode goes through a 1 k ohm res to ground. The plate goes through a 47 k ohm 3 watt resistor to B plus 3, 370 volts. The plate also goes through a 510 ohm res then a 100 p f 500 volt capacitor to B plus 3. The plate also goes through a 0.1 u f cap then a 1 k ohm res to the grid of another triode V 1 B. The junction of the resistor and capacitor goes through a 130 k ohm res to ground. The cathode of V 1 B goes through a 1.5 k ohm res to ground. The plate goes through a 33 k ohm 3 watt res to B plus 2, 400 volts. The plate also goes through a 0.22 u f cap then a 1.5 k ohm res to the grid of a beam pentode tube V2. The junction of the resistor and capacitor goes through a 75 k ohm res to bias, minus 20, or minus 70, uncertain, it is hand written. The cathode goes to ground through a 10 ohm res. The cathode also goes to a pin jack. The beam forming electrode connects internally to the cathode. The screen grid goes through a 470 ohm 3 watt resistor to screen supply, 240 volts. The plate goes through the primary of the output transformer to B plus 1, 460 volts. The plate also goes through a 5k ohm 5 watt res then a 2.2 n f 1200 volt cap to B plus 1. The plate goes through a 180 k ohm 3 watt res then another 180 k ohm 3 watt res to the plate of V1B. The output transformer is labeled Hammond, 125 something S E. The secondary has 5 leads coming out. The bottom lead is grounded and is not labeled with a color. Working upward the leads are labeled gre, org, yel, and wh. These four leads are shown connected to the stators of a 4 position rotary switch. The rotor is shown set to the yel lead. The rotor is connected to the upper speaker terminal and the lower one is grounded. Connected across the speaker terminals is the series combination of an 8.2 ohm 5 watt resistor and a 0.1 u f 630 volt cap. The upper speaker terminal goes through the parallel combination of a 2 k ohm res and a 3.9 n f 630 v cap to the cathode of V1B. V 1 is a 5687 and V2 is a KT88. A legend says 15 wpc SE amplifier, one channel. A power supply schematic is not provided. End verbal description.

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