02-13-2012, 01:33 AM
Transient peak plate current!
As the source voltage goes up or as you increase the capacitance in a capacitive input filter you have to increase the plate source impedance or you risk exceeding the transient peak plate current and the tube striking an arc and making a bad mess of things. (end of tube, cap and xformer)
I now recall a Majestic cathedral and an experiment with a 47uF 450 V cap that ended quite badly.
Now I'm gonna have a beer and kill off that brain cell for good.
![Icon_clap Icon_clap](https://philcoradio.com/phorum/images/smilies/icon_clap.gif)
As the source voltage goes up or as you increase the capacitance in a capacitive input filter you have to increase the plate source impedance or you risk exceeding the transient peak plate current and the tube striking an arc and making a bad mess of things. (end of tube, cap and xformer)
I now recall a Majestic cathedral and an experiment with a 47uF 450 V cap that ended quite badly.
![Icon_redface Icon_redface](https://philcoradio.com/phorum/images/smilies/icon_redface.gif)
Now I'm gonna have a beer and kill off that brain cell for good.
John
Las Vegas, NV USA