What are the Jumpers (Links) used for?

There are five Jumpers (Links) labeled J1 to J5 on the PCB.

	Jumper J1 (Speaker) is used to select either internal or external speaker operation. The default setting is for the Internal speaker with the link bridging the top two pins (position A). If an external speaker is used, the link must be moved so that it bridges the bottom two pins (position B).
	Jumper J2 (Direct) is used only if the tone-ringer is operated by a DC source (instead of the normal AC ring voltage). The default setting is for an AC ring supply (link open). If a DC source is used, the two pins on jumper J2 must be bridged.
	Jumper J3 (Speaker) is used to connect the Internal Speaker that is mounted in the front-cover of the tone-ringer to the PCB. Check that the speaker wires are plugged into this link-block before replacing the cover on to tone-ringer.
	Jumper J4 is used to select either "normal" or "reduced tinkle" operation. The default setting is "normal" with the link bridging the bottom two pins (position B). If "reduced tinkle" operation is required the link must be moved so that it bridges the top two pins (position A). The "normal" position is used for the majority of installations.
	Jumper J5 (Hytel) is not used.

Further details are available in the product's installation instructions.