That was one of my first hacking projects. By pressing two numbers simultaneously, it would tune "between the band" - which is where the pay channels were.

Essentially, analog "scrambling" back in those days obfuscated the picture by pushing the transmit frequency in between the channels. Say channel 50 operated around 45MHz. Channel 51 operated around 50MHz. When you pushed the "channel 50" button, it would tell the box to set itself for 45MHz. You'd see the picture. If it wasn't quite clear, you could twist the little wheel on the side. That wheel would alter the tuning +/- 2MHz or so. Eventually, you'd clear up the picture - provided the actual transmission was between ~43-47MHz.

Premium services would land in between. In this example (using made up numbers entirely), the pay service would place itself at 47.5Mhz. If you pushed the 50 or 51 button and turned the wheels all the way, you still wouldn't get a clear picture. Thus, the channel considered itself "scrambled" and unwatchable.

However, those early boxen were analog too. If you pushed both buttons (and shimmed them with foil or something), it'd split the difference. Voila! Cleared up premium picture (usually bewbs!)!

Eventually, the cable boxen were redesigned so that the circuit was "break before make" - meaning pushing one button shut off any others. That put the kibosh on this simple trick.

However, it was on to the next trick. Taking a few bucks of allowance to the RIchland Mall Radio Shack for 75-ohm coax, a varistor, a capacitor, and a soldering iron meant (with the help from the nerds at the D&D gaming room) the construction of a rudimentary "super-tuner" that let me inline vary the outbound frequency of the carrier. It was up and running in time for the next episode of "Softly From Paris".

It's amazing how much technology has been driven by the prurient interest! Thanks for the trip down memory (mammary) lane!