Also FB group Building Transistor Radios 2019-11-16 I was working on an AM radio that had a driver transformer with an open primary. I slit open the wrap and found the tiny fine wire on the right was loose so I soldered it to the heavy wire. But it was still open. ☹️😱 So I
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I’ve often had to kloodge together an audio transformer, jacks and other stuff to make a medium impedance output match a low impedance headphone. But it turns into a mess of wires and parts dangling from a transformer. I thought about what I would do to make a box with the necessary stuff, like inputs,
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from FB group Regenerative Receiver… Apr 8 庄议翔 The power transformers have the laminations interleaved. The first lamination has an E then I, the next one has I then E. So the transformer core does not have any air gaps, because it does not have any DC flowing through the windings. The transformers for single
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For FB group Building Transistor Radios This is the idea that I had about using more than one transformer to connect their windings in series or parallel to get a higher impedance and a higher stepdown ratio. My idea was to be applied to the Bogen T725 line matching transformer, but it could be applied
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I bought several of these miniature audio transformers from Electronic Goldmine. They are encapsulated so I can’t see anything, windings, core or materials. There are 5 pins, 2 on one side and 3 on the other, but the center pin measured open, so it’s apparently there to make sure the transformer is inserted the right way. The
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I was asking about very old capacitors and their shelf life on FB vintage test equipment group. The guys tell how good the old capacitor testers are because they have the “magic eye” to check for leakage. I was thinking that it would be easy to test any capacitor for leakage. All that’s needed is
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from a comment I added to this YouTube video https://youtu.be/GCh2LVHUavQ The main difference between a power transformer and an audio transformer is the way the E and I laminations of the core are arranged. The power transformer has an E on the left and I on the right of the first layer, then an I
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