Radios that can be operated in the dark with one hand.
Battery in square enclosure acts as on-off switch, programme selector, volume control and power supply.
No buttons, dials, sliders or other moving parts.
Because radio can be operated in the dark, all parts can be transparent.
Simple construction, electronic components all on simple base board.
Battery in circular container controls on-off and station by pushing in and releasing. Volume is controlled by rotating battery.
More compact than Version 1 but a little more difficult to operate with one hand.