Circuit board of the amateur Radio86RK computer. This computer has been assembled shortly after specs were published and was operational for about five years. The memory has been extended to 32 KB, stacking memory chips vertically (all pins are shared, except the selector pin that has been bent apart for the upper row, to be connected to the separate bus). The place of the second interface chip next to the large connector is empty (it has been dedicated to various experiments and was not required for the ordinary peripherials to work). On the bottom right, the amplifier for the tape data recorder can be seen. Hand assembled and photographed by uploader.