ok thanks that helps alot as I was not pressing the P4 while I turning the selector dial. I don't have any bad tubes yet but I will keep looking.
I don't like that the 800 does not have a noise test like the other Hickok models but I have never used the other models with noise test to know if works well or is accurate way to tell if a tube is noisey. Thanks for your help.
I don't like that the 800 does not have a noise test like the other Hickok models but I have never used the other models with noise test to know if works well or is accurate way to tell if a tube is noisey. Thanks for your help.