Scott, Germany-owned and operated since 1973, had been at the forefront of digital FM reception, alongwith Heathkit and SAE (west) and JVC (east).
A french october 1977 ad says that the T33S was the basis for Scott's 1975 RD1000 receiver - a prototype never released. The same french ad also says that the 1975-1977 period saw Scott register 150 worldwide patents related to Hi-Fi.
Also that the T33S suffers a frequency variation of only 0,0001% and that it has perforated cards acting as memory presets. Yes : perforated cards which the owner perforates himself with the Scott-supplied perforator !
Somewhat fastidious at first but sliding a card in to choose a preset station really has some of a sci-fi taste to it.
Really a hand-made automatism, just like the rest of the T33S which obviously was made in very small quantities and hand-made from top to bottom.
A more remembered competitor is the Toshiba ST-910 for instance but it came later and was built to the exacting industrial japanese standards...
Sony cautiously waited 1977 and never commercialized its early 70s ST-5555 prototype until IC integration got a bit more under control - and by which time, the T33S was a very old thing from the early days.
It seems the original Motorola ICs were replaced by Siemens ICs in the samples made for Europe - which is where most ended up anyway as the T33S really was developped there : all T33S were hand-assembled in Germany by SYMA, Scott's distributor but in fact much more : the "S" in T33S means Syma...
Thanks to Dirk, Steffen and Klazien who have all provided a lot which only owners and restorers can provide !
Dirk has also gracefully provided the code for the memory cards - "call letters" in Scott lingua.