Thanks very much, Brooke. Much appreciated! I like the pentode emulator -- it's a compound FETRON. Triple the FETs, triple the fun. -- Tom On 8/30/2025 5:12 PM, Brooke via ARC5 wrote: > Hi: > > I've added some information and patents on solid state tubes at: > https://prc68.com/I/USM159.html#SS_Tube_Replacements