Found two of these when going through old stuff. They are probably 10-15 years old and I have no clue whatever, what they are. R is ca 150ohms each side. Core is 91mm high, 80mm wide and thickness is 33mm. I have not unpacked my test equipment since we moved to another town a few months ago. Measuring inductance could have helped. It might be Electra-Print, as I bought some stuff from there, but I am not sure. Anyone who recognizes it wrt to building style, cables etc? Could be a large 1:1 interstage?


Yes, it looks similar to the Electra Print single ended interstage transformers that I used to have.
But it appears to have Interleaved E's and I's, no DC allowed.
So perhaps an interstage that only allows AC signal. An interstage for a high power parafeed driver tube stage, perhaps?
But it appears to have Interleaved E's and I's, no DC allowed.
So perhaps an interstage that only allows AC signal. An interstage for a high power parafeed driver tube stage, perhaps?
Looking close, it seems to have a small gap on each side in every laminate, might that do for gapping?But it appears to have Interleaved E's and I's, no DC allowed.
Found this: https://en.wikipedia.org/wiki/Air_gap_(magnetic)

No, Each side has I's and each side has E's. I's on both sides, the interleave is not a reNo air gap, no DC.
Single ended has all the I's on one side, and all the E's on the other. A single air gap, and no interleaved E with I.
I owned both push pull and single ended interstages from Electro Print Audio
Single ended has all the I's on one side, and all the E's on the other. A single air gap, and no interleaved E with I.
I owned both push pull and single ended interstages from Electro Print Audio
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Remember I had a never realized project with PP anode chokes, where the driver should run at 20-30mA. Must find my inductance meter!
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