While I know something about the electronics/onboard computers of newer probes (like that MESSENGER uses 4 single-board radiation resistant RAD6000 computer based on IBM's POWER1 CPU clocked 25 Mhz, and saves instrument and picture data on 2 solid state recorders 1 GB each),but I am very curious about what did they used on probes and satelites in the 50s,60s,70s and 80s.All that I know is that Voyager probes used digital tape recorders to save data and that even probes from the middle to late 60s used digital cameras but how it was possible to save and transmit these data to Earth or even send command to the probes with 60s technology?I know that there were computers in the 60s but I think that the smallest usable digital computers back then were as large as a refrignator and they had only about 1-4 KBs of memory, certainly not enough for photographs.Also I am interested about how are these probes commanded from Earth.By command, graphical interface, automatized processed or what?Sorry maybe it's a stupid question but I really have NO idea.

thanks in advance for answers