On the left is an AC plug. The bottom, wide, prong connects to the bottom end of the primaries of four identical transformers. The top prong goes through an on off switch to one end of a 1 amp fuse. The other end of the fuse connects to the top end of all four transformer primaries. All primaries are marked with a dot. The transformer symbols are arranged vertically and all four secondaries are in series. The top end of all four secondaries are marked with a dot. All four secondaries have a center tap. The top transformer is labeled T1 the second one T2 the third T3 and the bottom one T4. The junction of the on off switch and the 1 amp fuse connects to one end of a 5 amp fuse. The other end of the 5 amp fuse connects to the swinger of a S P D T switch. One side of the switch is labeled Output Above Line and is connected to the bottom of the secondary of T4. The other side of the S P D T switch is labeled Output Below Line and connects to the top of the T1 secondary. An eleven position rotary switch is placed to the right of the transformers. Position 1 is not connected to anything.
Position 2 goes to the bottom of the T4 secondary.
Position 3 goes to the center tap of T4.
Position 4 goes to the junction of the top of T4 and the bottom of T3.
Position 5 goes to the center tap of T3.
Position 6 goes to the junction of the top of T3 and the bottom of T2.
Position 7 goes to the center tap of T2.
Position 8 goes to the junction of the top of T2 and the bottom of T1.
Position 9 goes to the center tap of T1.
Position 10 goes to the top of T1.
Position 11 is open.
The rotor of the switch goes to the top line of the output. The bottom line of the output goes back to the wide prong of the plug. The junction where the bottom of the T2 secondary connects to the top of the T3 secondary goes to a point labeled Optional Mid-Point Connection. See text. A label applies to all four transformers. It states, 6.3 volt at 4 amp. Hammond 166N6. End verbal description.