[Dumb] Using a gas cooker

[TJM]

I just moved into a new house and have found (to my horror) that the oven is gas heated. Turn the knob, hit the ignite button thing and then a small blue flame appears at the back of the oven.

There's no manual and I've never used an oven like this in my entire life. The only control is a knob that turns from big flame to small flame (helpful). Could any gas oven users shed a light on how hot 'big flame' is and how long it takes to heat the oven? If it helps, the unit is a tall and white oven/stove combo made by Lyric that looks ancient. I'm actually pretty sure I saw it in Ashes to Ashes two weeks ago.

 

[TJM]

Sure your not using the grill controls?

Ya, it's marked Main Oven and there's a separate one for the grill.

The knob has no numbers on/near it - once it's moved from the off position, there is a symbol for a big flame, followed by a bar that gets thinner until it reaches the small flame symbol at the end. There are no steps - turning it from off through maximum heat to minimum heat is one smooth motion.

Edit: Ok, to hell with it. Thrown in a pizza at medium heat and will see how long it takes to cook.