Thanks for the link, tomcat. (A friend of mine used to call me that.) That's one of the sites I was using to try to figure out the "Stepup". Between that page and the Vinyl Engine pages and information at the Jensen and K&K website and some more work with a custom spreadsheet, I think I'm getting it figured out:
Loadings of 363, 131, and 44 Ohms come from turns ratios of 7.3, 12.2, and 21.0 using a "Rtot" of 19,500 Ohms from the 39k resistors, but I'm not sure how the circuit/switches are used to get the 19,500 Ohms. That part of it is still a mystery to me, and I'm not exactly sure what the function of the 160k and 82k resistors is.
From the "base" loadings of 363, 131, and 44 Ohms using switched resistors of 392-133-39, you get resistance settings of 189-97-35, 98-66-30, and 40-33-21. This part of it is straightforward.
I'm beginning to understand transformers and resistors but am still a long way from really knowing how they work. Interesting stuff, especially when thinking about how it all affects LOMC cartridges.
Tom
