To encrypt captures, you must upgrade to the paid version, which also removes the Download from the right, and you can position computers on the main graphical grid for seamless control.The grid size is easily adjustable from 3x3 to 7x7.Originally, 1N914 diodes were used, which were later replaced with 1N4148 since RAT2.The 'Turbo RAT' pedal uses red LEDs for this purpose (red LEDs have about a twice as high forward voltage as the original silicon diodes), while the 'You Dirty RAT' pedal uses 1N34A germanium diodes (clipping at a lower forward voltage). Rat serial numbers aren't coded in any way, but I've seen much lower serial numbers on the Vintage Rat Reissues that were made at the end of their production run.In particular, the op-amp and the codes on the pots (if there are any) are useful. If you post a pic of the guts, I can pin it down for you.If you often find yourself browsing i Books and you'd like to be able to do so without opening i Tunes every time, this could be a handy widget for you.
But based on what I've seen, a serial number in the 80,000 to 100,000 range dates back to around 1988 - the period when the RAT-2 was released and the original Rat (small-box, black-face) was discontinued (there was an overlap).
It displayed both secure and Download from for a DVD.