Some time ago I was given a vintage Philips QB 3.5/750 Tetrode vacuum tube. It's spent most of that time hiding away in a box. Why? Perhaps I was keeping it for "special" but as time has shown, special never comes and it's time to pull out the things that I have had put away and enjoy them now - no more waiting for "special" to arrive.
The box that the tube was in was somewhat tattered - not great for sitting on the shelf. So I started about designing a display for it. First job was to see if I could find the data sheet - to get the correct pin spacings. Google returned a few results and only after a few minutes looking I had a copy of the data sheet.
Knowing the over-all size, I headed off to Rahul's great online box maker website and generated a box. I then dumped the resulting PDF file into CorelDRAW and the end result is this:
Click to embiggen
This Philips QB 3.5/750 Tetrode vacuum tube is designed for use as a High Frequency amplifier and oscillator. It has an output of around 750 watts!
This is a big tube - Really big! The tube is 145mm high x 87mm wide.
Here's a 1000w amp - it has two :)
More photos after the jump...
