[John10b]

This is getting interesting and a little puzzling. In your first and subsequent posts you say words to the effect “ changed all the components........it was working till I change the STYLUS ...”
Let’s stand back for a moment and recap.
1. It was working to start, you say.
2. You changed the stylus ( not cartridge).
3. Then it became faulty.
4. You changed all the components.
5. Cathode voltage is rather too high at +17volts.
6. Only faint buzz when you touch control grid.

So what caused it to become faulty after you changed the stylus?
I presume you didn’t disturb any part of the amp.
It is quite common for an amp to go u/s after switching on/off/on.
Did you make an error when you “changed all the components “.

Considering all that’s been said, I would double check every thing you have done and if you are satisfied no mistakes were made I would pop in a new valve.
Cheers
John