Lewm: The way a degausser will magnetize is to turn it on, or off in close proximity to the item to be 'degaussed'.
The way to use any cheap degausser is to turn it on AWAY from the item to be degaussed. Then bring the degaussing coil or device up to the item and wave it around in smooth stokes and the slide it away smoothly. Once it is away from the item, then you can turn it off.
The item can be move up to the stationary degausser tool in the same manner if that is easier.
The specially made devices for degaussing Lps must have some method to prevent the problem, or the thing has to be turned on before the Lp is placed on it and after the Lp is removed...
The way to use any cheap degausser is to turn it on AWAY from the item to be degaussed. Then bring the degaussing coil or device up to the item and wave it around in smooth stokes and the slide it away smoothly. Once it is away from the item, then you can turn it off.
The item can be move up to the stationary degausser tool in the same manner if that is easier.
The specially made devices for degaussing Lps must have some method to prevent the problem, or the thing has to be turned on before the Lp is placed on it and after the Lp is removed...

