Hey guys,
The other tubes I have.... one doesn't have a marking that I can find and the other 2 are not pentodes, ones a rectifier and the other was some kind of regulator tube.
My dad has a box of random tubes I am looking through now.... not seeing any #43's..... theres a couple #80 and #78 a 6D6, a 12SK7 (is this one a possibility? the datasheet is pretty vauge... I will search for a better one)..... and some that are not pentodes...... I take it i need a pentode for this? I have a #32, but thats a tetrode according that datasheet site.
The enclosure is not a problem, but looking at the circuit, I take it I would have 100v + across the code key, and thats not cool.
My local ham radio club has a homebrew program for the Feb. meeting and I wanted to make this old tube oscillator and a old fashioned straight key to go with it. So the voltage at the key needs to be a safe level.
EDIT - here is a better 12SK7 Datasheet - **broken link removed** problem is I don't know what exactly to look for on it as to minimum voltage ranges.