How to add sound to amateur films (1954)

Danger: Live Chassis A serious warning must be issued here. Never touch the chassis of a live-chassis radio while it is plugged in, even though it may be switched off. Neither must you attempt to connect to earth the chassis of such a set. If you go about things in the wrong way, you may receive a fatal shock. Unfortunately there is no really safe and simple way of telling whether or not your set has a live chassis. So if you are not familiar with such matters, consult a radio serviceman. He will, if necessary, make all the connections needed for the record player and assure you that there will be no danger in using it. Provided, however, that you make your connections only to the sockets marked "Pick-up", you cannot go far wrong. Having connected the screening of the pick-up lead to the appropriate socket, there may still be a little hum. This will probably disappear when you connect a wire between the framework of your turntable motor and the screening of the pick-up lead. Alternatively, try connecting the turntable framework to earth. (There is no necessity to run a wire to a metal plate buried in the earth. If your electricity points are properly installed, the large, third pin of a three-pin socket should be amply good enough. Alternatively, scrape the paint from a cold-water pipe and fit an earth clip. But do not use a gas pipe as an earth, it is a highly dangerous practice.) Do not feel alarmed at these warnings right at the beginning. But having warned you against the misuse of your equipment, we shall explain how to use it to the best advantage. Volume Control If your record player does not already boast a volume control, you must either provide one or get a radio serviceman to fit one. The pick-up leads should be soldered to the outer two of the three tags on the volume control. One of 12