Wiring the $200 autoformer.

As intimidating as it may seem, wiring an autoformer is really quite simple. Here are the basic ideas you need to understand in order to successfully wire one up.

The basic layout of the taps is simplified by the use of the PC mount bobbin. The two flying leads are the signal input and ground wires and each pin represents 3dB of atteuation as shown below. (as viewed from the bottom)

For a basic installation all that is needed is some form of switch, Input and output jacks, and an enclosue. The basic wiring diagram for one channel looks like the image below. The selector switch is only required if more than one input is desired.

Thats all there is to it! Pay close attention to the switch rotation. When the switch is rotated all the way counterclockwise (off) this is where the ground connection goes, then as you rotate the switch clockwise you simply connect the taps in order (-42, -39 etc.). If you reach full volume (the signal in lead) and still have remaining taps on your switch, simply connect them all together or insert a stop to prevent any contacts from being left open. Further questions about hookup can be asked in the forum.

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