I never throw things away if I think they have future use or can be scraped or recycled. A friend called yesterday asking if I had a sonar he could use for a "memorial" fishing trip, his son-in-law and a good friend of mine died of COVID 1984 2 weeks ago, and his sonar quit working. I checked my sonar bin and found a early 90's chart plotter and a sonar that was better than what he had but compatible with his transducer and plugs. I asked him if he checked the fuse and he said "what fuse". He cut loose bundled wires and found a hidden inline fuse (I hate them) and is machine works but has a failing screen. The one I gave him was a take out and was working when I replaced it with a mid 2000 one for a friend. I told Chuck it was a "vintage" sonar (old used up junk in e-bay talk) and they are no longer made and were priceless. What is "priceless" is transducers and power cords, and I have both, including a GPS antenna.
During my bin diving I found a good used Arimar P66 transducer for a Garmin, a over priced NMEA power cord, Blue Sea System fuse block and ACR I needed for the radar/auto pilot install on my 16' C Dory so I did get "paid" for the time. I also found a really old Lowrance green box that I forgot I had, it still works.
Those green boxes aren't worth a whole lot any more. More nostalgia than anything else. You can find them for $25 all day long with the transducer 4around here.
I remember using the paper machines in my younger years.
I have one of those too, and a Raytheon V700.
I used a Garcia paper graph like this for years. It still works! I got tired of buying paper so now I use an old Lowrance X5 LCG from the mid '80s. Top of the line when I bought it. :) I like to give the fish a fighting chance these days. ;) :D