96 - "They weren't able to measure the potential, but fortunately, they didn't lose the Shuttle when it blew up from the current it had generated."
"Actually the tether got stuck in the reel."
I think youall are both right. IIRC There were several experiements, and none completely successful.
TSS flew on two missions. In the first, it got stuck. In the second, it made it out to 20 km, and did in fact generate a significant electrical current (until the tether broke) --seems to me it was a couple of amps at a healthy voltage.
The orbit of the increased tens of miles (it was traveling above the CM, and thus faster than orbital velocity at its altitude), and the Shuttle moved downward several miles.