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There are two types of Beogram 1500;
The earlier type with round arm and SP cartridge has no transport screws.
The later type with square arm and MMC cartridge has three screws visible if you lift off the platter.
Put a piece of soft foam or similar in above and under the tonearm,
sandwich it in a way to make a soft squeeze when the lid is closed
to stop the tonearm from bouncing about.
Martin