17-04-2014, 09:11 PM
Many thanks for the replies. I have added some more photos to show the individual bits.
The construction starts off with the black 4 arm frame. Onto this is mounted a brass block which is held to the black frame with two screws with springs on them. There is then a centre screw, also with a spring, in the centre of the brass block. This screw pokes out through the centre of the speaker grille on the front of the cabinet, so is obviously meant to be user adjustable. As this screw in the middle of the brass block is turned, it moves the plate with the letter box hole (notice it widens out on the underside), and the coils mounted on it, nearer or further away from the copper coloured strip with the thread in it which goes to the centre of the cone. The screws holding the letter box hole/coil plate also fix the horseshoe magnet in place. One interesting thing I have just noticed in taking the latest photographs is that one side of the brass block has a + sign on it. Could this be to ensure the magnet is fitted the correct way up? I have also attached a photo of the underside of the copper coloured strip with the thread on it. Maybe something could have been attached there to go into the letter box shape hole, but I can't see any obvious way it would have been fixed. I don't know what these "reeds" look like anyway. When the coil/letter box plate is moved up towards the copper strip it magnetically attracts the strip very strongly.
I hope this helps to shed some light on things. There is audio getting to the coils by the way.
Thanks
Trev
