Tower bells as external bells - Overview

Abel can be used in the tower where the bells are tied and Abel is used to produce the bell sounds in the ringing chamber. There are essentially two ways you can use Abel: either as a simulator, where you use one or two tied bells and Abel rings the rest; or as a sound generator (true "silent practice"), where all the bells are tied and Abel is used only to generate the bell sounds.

For both simulator and silent-practice operation, the bells must have sensors attached to them so that Abel can detect when the bell would normally strike. If you are using one of David Bagley's "Multi-bell interfaces" to connect to Abel, David will advise on sensors for use with it. Otherwise, you can make your own sensors: making sensors to attach to bells is not difficult, though you will need to be competent with a soldering iron. There may also be commercially-produced sensors available (but not from the suppliers of Abel) that may be appropriate for connecting to PCs.


NEVER work on a bell that is up. Attaching sensors to bells means that you will have to attach reflectors or electronic apparatus to the wheels or bell frame. You should always do this with the bells down.

If you are doing a tower installation of Abel, it is up to you to comply with all regulatory standards for wiring (including standards about proximity of mains-connected devices and wiring to lightning conductors, to which metal bell frames are often bonded), church rules for changes to the building, etc. The authors of Abel, and AbelSim Ltd, are not responsible for work you do in the tower, and do not guarantee that the circuits given in Abel documentation can be made to conform to any such rules and regulations.

There are at least four categories of sensor you can use. Which ones are suitable for your belfry depends much on local technical skills, and how weather- and light-proof the belfry is.

Click on the following items for instructions on how to make bell sensors to proven designs:

  Optical sensors
  Proximity sensors

WARNING - if you connect dummy handbells or tower bell sensors to the serial ports of your PC you do so entirely at your own risk!

See also:

  Connecting bells using the serial port
  Connecting bells using the Multi-Bell Interface
  Handbells as external bells
  Using external control switches with Abel
  Configuring Abel to use bell sensors
  Configuring Abel to use control switches