Schematic diagram of the power supply for the headphone amp. One side of the line cord goes to the bottom of the primary of the power transformer. The other side of the line cord goes through a switch then a 1/2 amp fuse to the top of the transformer primary. The transformer has two secondaries, which are labeled B plus 250 dash 0 dash 250 v at 50 mA, 30 mA minimum and 6.3 v at 2 amps 1.5 minimum. The center tap of the B plus winding is grounded and each end goes to the anode of a solid state rectifier. The cathodes of the two rectifiers are tied together and go to the plus side of a 20 mike cap. This cap goes through a 1k ohm 1 watt res to the plus side of another 20 mike cap. This cap goes through another 1 k ohm 1 watt res to the plus side of an 80 mike cap. this point is labeled B plus 1. B plus 1 goes through a 33 k ohm res to the plus side of a 25 mike cap and this point is labeled B plus 2. The negative sides of all 4 caps are grounded. All four caps are rated at 450 volts. One side of the 6.3 volt winding connects to pin 9 of all four tubes in the amplifier. Each tube has pins 4 and 5 tied together and they all go to the other side of the 6.3 v winding. One side of this winding goes through a 150 ohm res then another 150 ohm res to the other side. The junction of the two 150 ohms goes through a 10 k ohm res in parallel with a 5 mike cap to ground. The junction also goes through a 150 k ohm 2 watt res to B plus 1. End of verbal description.

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