Oh I know just what you mean. I had to put the pot back and the zeners for the bias adjustment that was so fun lol. You made me wonder because my 6 tuber have another variable cap on top by the pi circuit. I was curious. No matter what I've done it won't go below 1.7 I am not to awful concerned it's been strong since I recapped it.If you got the input to adjust with the tuner in the picture, then don't touch the other ones especially if you don't know what they are for. I know at least one of them is for bias tune, and I have no idea what all the others do.