#dynohub lighting

[thephotoblue]

STURMEY ARCHER FILTER SWITCH UNIT

The electronic switch unit inside the Dry Battery Unit available as back up power for the Dynohub.

R20 is another code for D cell.

The single diode prevents the rectified dynohub voltage from getting to the batteries (except by the bleed resistor which is an 'extra' - see text).

Note the batteries are the wrong way round!