One source for a pretty good dial is an old tube type stereo receiver at a garage sale or Goodwill store, or ? the cord dial mechanism can be used if you have the room. In fact, I figured out the small Heathkit transceiver pulley on the cap will give you a 7" travel. Or make a drum out of an ARC-5 transmitter output coil ...you can probably use the window too. I think I have one. 73 Kees K5BCQ