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Partridge MC transformers (Part 1)

Today, I found a pair of Partridge mu-metal core mic transformers labeled "973A". Seller knew nothing about them unfortunately. Well, they're actually quite popular, and a quick search reveals that these have a 1:16 step up ratio. So far I only have experience with Partridge 977 step ups, which I paired a long time ago with Ortofon SPU mono. They're typically pretty grimy appearing - today's were no different:



If you are new to these step ups, the two pins already wired together are ground, while the other two have red and white insulation:



To figure out which is the input and which the output, measure resistance with your multimeter. The pin with the lower value is input.

My pair measure roughly:

White pin: 2 ohms dc (input)
Red pin: 240 ohms dc (output)

The retention brackets were in horrible condition and took nearly an hour to re-place. Yes, I plan to put them in a box. Soon...



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