this criciut is for sine wave genrator using the IC called NC-1458 which have 8 pin's but criciut seing 4 is he using one IC ?.... after design from where we know it,s genrating sine ware
Well, obviously they are the same node and it is very poor practice to give the same node more than one name, so I might assume that really there is a physical connection point there like a connector or some other means or physical connect-disconnect. If this is the case, it is also poorly drawn because they are not drawn properly..
It's simply wired as an adjustable resistor, giving just two connections. When they are wired using three connections (like a volume control) it's called a potentiometer.