Neat to see a Rob Robinette article pop up here, his website is a fantastic resource for guitar amp work. His articles on Amp Startup and Troubleshooting were particularly helpful when I built a tube amp for the first time. I hadn't heard of using an incandescent bulb as a current limiter in startup before, I was glad to have additional options for trying to make the troubleshooting process a bit safer given the high voltage involved.