Schematic diagram of power supply. One prong of the 120 V A C power plug goes to one side of each of 3 transformer primaries. The other prong goes through the on/off switch then a 1/2 A fuse to the other side of the 12.6 v transformer primary. One side of the secondary connects through a 9 ohm 3 watt res to the AC input of a bridge rectifier. This resistor is made up of 3 27 ohm 1 watt resistors in parallel. The other side of the secondary goes to the other AC input of the bridge. The positive output of the bridge, two cathodes, is grounded. The negative output goes through a 4700 mike cap to ground, positive end grounded. This negative power supply, V minus 2, goes to the emitter of the relay switching transistor, NTE375. The collector of this transistor goes through the relay coil to ground. There is a diode in parallel with the coil with the cathode to ground. The base of the transistor connects through a 22 k ohm res to pin 1 of the radio socket. The relay contacts are two pole normally open. One of the contacts connects to the on/off switch away from the AC plug. The other side of the relay contact goes to two 1/2 amp fuses. The other end of one of the fuses goes to the primary of the 6.3 volt transformer and the other fuse goes to the primary of the 24 volt transformer. The other relay contact connects to V minus 2 and the other end will be called V minus 3. V minus 3 goes through a 360 ohm res to the anode of a zener diode, 6.3 v 1 watt. The cathode is grounded. A 5 k ohm pot is connected in parallel with the zener and is labeled filament. The wiper connects to the base of Q1, 2N3904. The emitter of Q1 connects to the emitter of Q2, another 2N3904 and through a 7.5 k ohm res to V minus 3. The collector of Q2 goes to ground. The collector of Q1 goes to the base of Q3, a PNP T O 220 of any type. The emitter of Q3 is grounded and the collector goes to the base of Q4, 2N3055 or equivalent. The collector of Q4 is grounded and the emitter goes through a 10 ohm 10 watt adjustable resistor, not a pot, to V minus 1. The emitter of Q4 goes to pin 7 of the radio power socket. This point also goes through a 1.1 k ohm res to the base of Q2. V minus 1 comes from a bridge rectifier on the secondary of the 6.3 v transformer. The positive of the bridge is grounded and the negative goes through two 4700 mike caps in parallel to ground. The negative of the two caps is V minus 1. V minus 3 connects to the top terminals of two 5 k ohm pots. The bottom terminals are grounded and each wiper has a 1000 mike cap connected from it to ground. Positive side grounded. One of the pots is labeled AGC bias and its wiper goes to pin 4 of the radio socket. The other is labeled output bias and its wiper goes to pin 5 of the radio socket. The secondary of the 24 volt transformer is connected to the 24 volt winding of an identical 24 volt transformer. This second 24 volt transformer is turned around backwards. The 120 volt winding, formerly the primary, is connected to the AC inputs of a bridge rectifier. The cathodes are grounded and the anodes connect to the positive of a 150 mike 150 v cap. The negative is grounded. There is an 18 k ohm res in parallel with the 150 mike cap. A 330 ohm 1 watt res connects from the positive of the 150 mike cap to the cathode of a 130 v 10 w zener diode, see text. The anode is grounded. The cathode of the zener goes to pins 3 and 6 of the radio socket. End verbal description.
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