Garbage...the only reason I use the large cap is because I also pull the 6.3v I need for the 2 other tubes in the circuit off of it. If you can get a linear regulator to work for your 5v I think you will be very happy with the lack of humm. I remember blowing up the first regulator too...check your grounding. just ground the whole filament circuit once. Think I mixed things up over by the tube socket by running twisted wires over to the tube sockets and putting on another ground wire over there...ooops! Mel
Ferrite beads help with reducing transmitting or picking up high frequencies but will have no affect on 50 or 60 Hz hum. The first thing to determine is what frequency is the hum. Is it line frequency 50/60 or is full wave power supply frequency 100/120 Hz? Got to know that. It could be a combination of both and require more than one solution.
