sensing for the number of spokes can be done when power is initially turned on depending on how many slave arrays are detected the internal timings of the microprocessor can be adjusted to generate the appropriate patterns with a larger number of slaves the consistency image quality and persistence to the observer is significantly better particularly in is lighted areas each slave can also include a battery compartment for additional batteries power available from any of the arrays can be combined to operate the apparatus a configuration including a single master and multiple slaves can continue to operate even when a number of slaves or the master has dead batteries only one of the arrays needs to have good batteries and these good batteries power the entire apparatus a memory connected to the microprocessor can store a large number of patterns images and messages for example hundreds these images can be played out in a random sequential or fixed pattern selection of the playback method is done via the pushbutton switches 108 located in the master array see fig1 fig3 a 3 f show additional possible patterns for example spokes rings a spiral letters petals and a geometric pattern in the usual case.