There's only a dial
Water level for the wash is selected in the area of the timer above FILL. For full loads, you just start it there and let it fill, after you have selected the water temperature at the tap. I don't know if this was a one fill hose machine or if it had separate hoses for hot and cold. For less than full fill, you start the timer in the area marked FILL, then when you have the desired amount of water in the tub, you pull out the dial.pointer to stop the fill and advance it to any of the time periods below FILL. Once the wash portion of the cycle started, you would have to adjust the temperature for the rinse unless you were using the same temp for both. Many brands offered the lowest of the low model with no water temperature switch, GE, Frigidaire, WP, Kenmore, Norge, Bendix & Philco. I saw a really basic GE washer in a store that had a speed selector switch and one cycle but no water level or temperature control. It only had one water valve and fill hose.
I like the DD WP machines because I can get them to do the spin drain and yes, John has told me numerous time about straining the stuff back through the load, but it does not make a problem for me in the KA, either of the Maytags, the V-12 GE, nor in the 1-18 or solid tub Frigidaires .