Yep. It’s here alright, I actually drew the schematic up on this one! –
Check it out. Note that the power supply in the scheme is not the original switching type as used in the nano. It’ll make no difference to the sound, all the power supply needs to do it provide 230VDC to those plates! You could sub in the power supply from this amp here: http://jjs.at/electronic/class_a_subminiature.html
Demo video:
This was kindly provided by a freestompboxes.org member, many thinks 🙂
View the thread here: http://freestompboxes.org/viewtopic.php?f=2&t=511&p=55083#p55083
Here are some good links regarding sub-mini tube amps – http://amps.zugster.net/projects/subminiature