All the hardware was primitive by todays standards. The Telemetry Processors that I worked on ("MSFT2" - Manned Space Flight Telemetry 2nd gen) had a paper tape reader to load programs and a 4K core memory and all discrete transistor components. The data output was either a two digit "nixie" display, Digital to Analog converters for external devices like a pen strip chart recorder or an 8 bit parallel transfer to a computer (Univac's on the tracking stations). The PCM Telemetry data stream from the spacecraft is a TDM (Time Division Multiplex) data stream with a sync frame and 127 (usually) frames of data. The frames of data can be multiples (super commutated) for certain parameters (e.g. bio med data) or 8 bit frames (words) for a particular voltage measurement or they could be 8 different switches, with a bit being on or off corresponding to a particular switch in the space craft. They could also be sub-commutated where the data in a given frame can be different within a subcommutated rate (e.g. in frame 1 the data if for "x" parameters, in frame 2 the data is for "y" parameters and up to 8 different frames). I got into this, having worked as a Tech, as a programmer and as tech support on the machine.
"Realtime" data sent to Houston was not really "realtime" in today's sense. It was first manipulated and reformatted in the Univac Computers and then sent on 4800 BPS links to Houston, who had to take that data and format it for whatever use or display there. In addition, since the data downlink from the Lunar Module was at 72Kbps and the link to Houson was 4800BPS there were predetermined parameter programs that only transferred the selected data to Houston at steps within the mission.
This is probably more than anyone wanted to know on the subject.