2-phase doorbell transformer parlor trick

So grab a single-phase 120v/24v doorbell transformer, a couple 12v lightbulbs, some hookup wire and a dual-trace scope.
Apply 120v single phase to the transformer primary and connect the light bulbs in series to the transformer secondary as shown below:
( Transformer L1 ) ----------- ( lightbulb ) ---------- ( traitor's magic junction ) ---------- ( lightbulb ) ----------- ( Transformer L2 )
You should see the bulbs light up.
Next, connect a dual trace oscilloscope to the lighting circuit as follows:
- Connect the two scope trace common leads to ( traitor's magic junction ) between the lightbulbs.
- Connect scope trace Lead 1 to ( Transformer L1 )
- Connect scope trace Lead 2 to ( Transformer L2 )
Your scope will now display 180° 2-phase 24v output coming from a single phase transformer.
[Hugh Jorgan takes a bow]
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