The dreaded green spot on Midwest speaker
Having restored one of these , I could not resist it when a chassis came up on EBay fast forward a few month I decided to check the speaker to find that the energising coil was o/c , Ed kindly rewound it for me some ten thousand turns, but it came out a bit lower resistance than quoted in the circuit.
This is no ordinary speaker it has two coils the second one it tapped, after re assembling the speaker a thought came to me supposing the coils were connected wrong causing the magnetic field to cancel, how did I find the correct way, well I plugged the speaker into the chassis, switched on and was greeted with fantastic sound loads of volume.
I needed to prove my theory so fixed up a changeover switch as to reverse the two connections to the coil, the results were immediately much lower volume.
Next job is to restore the second chassis, pic of previously restored chassis. Mick.
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