That description sounds rather like the George Aldrich "Magnum" handle. I've never had one...may have seen one a decade or more ago. With more time to think about this handle, I'm pretty sure that some folks liked to hold the handle with the adjuster on the top, and others liked to hold it with adjuster on the bottom. Not for me, if it has cables. Howard learned that lesson in my behalf.
George sold the rights and production tooling for his handle to B&B Hobby in Spokane, WA but said he never got paid. He was pretty bitter about that. I don't think I've ever been to B&B Hobby, though I've been to Spokane quite a few times.
Steve