Well. I never used it before. And idk how to use it lol.
If I am correct, my grandpa used it back in the early 80s for one of his RC boats he had.
Dont even know if we have crystals around. And the receiver is way too huge to fit into one of the cars, plus the connections for the receiver are opposite now. Back then the pins were on he servo lead. Now the pins are on the receiver.
Got two replacement FM xtal less than six months ago from Futaba. They have an inventory of some, but not all xtals. Recommend checking with them before going to, say, Ebay or other after market source. Link I'm providing is not found. Not sure if it is inactive or under repair. Check with Futaba. Providing it as a place to start if you initiate a xtal search for the rcvr.
Another option is to send the entire xmtr and rcvr to Futaba for repair. Possibly then factory repair will include a replacement xtal not available on the retail market.
Here's an old Deans DM-100 system from the 60's. Robin from WS Deans sent me these pics as well as some other real vintage stuff he has. The link will take you to the Radio Control Hall Of Fame that tells about these in some detail.