After watching several YouTube videos demonstrating the construction of simple triode vacuum tubes I decided to build some. Cylindrical electrodes are classical in design and work well as triodes, but the assembly is more difficult to align reproducibly. I've switched back to the parallel plate style of the WE 101D and its ladder grid, though the ladder is more demanding to build compared to the early Audion's serpentine grid. I made the first ladder grid by just hand holding the pieces to weld them. This method is easy, but tedious. I'll use an aligning fixture for the next build.
The next part that needs attention is the filament. The original WE 101D's that I've looked at on eBay show an 'M' shaped filament. This is a simple arrangement if you're using a glass arbor to support and position the electrodes. I'm going to avoid using an arbor and just utilize the extra pins in the button pinch and run three filaments in parallel. I'm looking forward to getting one of these tubes processed and tested. I expect the electrical characteristics to be ostensibly the same as the original 101D. We'll see.
The next part that needs attention is the filament. The original WE 101D's that I've looked at on eBay show an 'M' shaped filament. This is a simple arrangement if you're using a glass arbor to support and position the electrodes. I'm going to avoid using an arbor and just utilize the extra pins in the button pinch and run three filaments in parallel. I'm looking forward to getting one of these tubes processed and tested. I expect the electrical characteristics to be ostensibly the same as the original 101D. We'll see.
