Hi,
I'm looking for a small pcb for the 6.3V/375 mA of an E188CC filament.
As it's a good Philips tube, I would like something with a soft start inside the reg to get rid of the in rush current in the filament during the switch on - I use SS rectifier with a CRC.
I know there are quite simple scheme with a LM317 and transistor/cap for the soft start.
I eventually thought about the great Mark Johanson gerbers of the Lm317 + denoizytor, but don't know if slow start enough ? but as this tube is a low noise low microphonic, I assume a Lm317 alone could maybe a little be improved.
Hoping for advice for something simple and chip; verroboard also is not a problem is simple enough.
Many thanks for your thoughts
I'm looking for a small pcb for the 6.3V/375 mA of an E188CC filament.
As it's a good Philips tube, I would like something with a soft start inside the reg to get rid of the in rush current in the filament during the switch on - I use SS rectifier with a CRC.
I know there are quite simple scheme with a LM317 and transistor/cap for the soft start.
I eventually thought about the great Mark Johanson gerbers of the Lm317 + denoizytor, but don't know if slow start enough ? but as this tube is a low noise low microphonic, I assume a Lm317 alone could maybe a little be improved.
Hoping for advice for something simple and chip; verroboard also is not a problem is simple enough.
Many thanks for your thoughts
if you want slow start lm317, lt1086 are good enough for that, yet fillament lifting will give the real edge over hum .
Last edited: