I'm doing research for a project, and I'm having trouble finding information about all the methods of recording data that were available to a scientist, amateur or professional, in the 1970s and 80s. I know that computers were not quite widespread enough to be used for smaller recording projects, like geological vibrations, and that chart recorders like this were often used.
But what if you needed a very detailed recording of an event, specifically of a waveform like radio signal or vibration? Were magnetic tape recording methods used? What about wax cyllinders?
If it helps, the specific application I'm interested in is radio astronomic recordings, of signals received from space. Thanks!
The ancient method of pen and paper was still in use (and is still in use today); this was a common method for amateur scientists, and was also in professional use. Photographic methods were also used. Of course, photography was a key method in optical astronomy, but it was used much more widely. For example, oscilloscope traces were photographed to record them, and this could be done on filmstrip to record a series of traces, one per frame. An advantage of photographic recording is that it isn't necessary to have a measuring instrument that produces an electronic signal. Chart recorders, which you note, were in common use. The bandwidth of a pen-and-paper chart recorder is limited by how quickly the pen can be moved, and higher-speed recording used a moving beam of light and light-sensitive paper; the beam of light would typically be steered by a galvanometer-driven mirror. This principle of optical chart recording was quite, having been used by William Lawrence Bragg (i.e., Bragg Jr.) in 1916 when he was working on acoustic location of enemy artillery (Bragg recorded on movie film; his main motivation was to use the galvo-mirror as a mechanical amplifier, since vacuum tube systems, and therefore electronic amplifiers, were still in their infancy),
The other widely-used method for high-speed data recording was magnetic tape. This was very common in radio astronomy which you ask about. Chart recorders were cheaper, and paper charts had the advantage of being human-readable. Magnetic tape had the advantage of the signal being easy to return to electrical form for further data processing. In the 1970s and later, astronomical data was typically stored on tape in a digital format; this required computers and processing power that wasn't readily available to amateur scientists, but was only a small addition to the cost of building and operating a radio telescope. For very long baseline interferometry, data from the various telescopes was transferred to one location by physical transport of the tapes (as the old saying went, "Never underestimate the bandwidth of a station wagon full of magnetic tape").
Microcomputers and floppy disk drives were being used for data recording in the 1970s, although it took until the '80s for them to become common. '70s computers might be home-brew systems or off-the-shelf, and by the early '80s, off-the-shelf systems dominated. 8" floppies were used in the early systems. Magnetic tape was still a clear winner for bandwidth and capacity; floppy disk systems were a cheaper alternative when high capacities and bandwidth weren't needed.
For a snapshot of the situation in radio astronomy in 1970, see: