If, like myself you have a old machine, it may not talk easily to a modern computer. My 2004 General Electric Logiq 100 apparently could talk to computers via a parallel port and a Windows 95 program however I would need a legacy computer just to talk to it, even if the program was available!
My machine does output a analog video signal however, provided for use with a thermal printer or a external monitor.
These C-DVR sell on ebay for USD15-25, coming with leads in and variably a manual and 12V power pack. They seem popular for those recording video for drone flying. Video comes out of the co-axial port on the back of the machine, into this blue box and onto a mini-SDHC card. There are no real controls – if there is video coming in and 12V power to the C-DVR it is recording. All live video coming into the box is recorded as an .AVI, you can then transfer the card to a computer and view with a program like VLC or MediaPlayer.
It is working well for me, only fault is that I have not worked out how to get rid of the time stamp on the bottom of the saved video.