One of the good things about Christmas is that I always managed to get some proper time for working on my projects. This year is devoted to my belated project: 4-65A SE amplifier. We bid farewell to our family guests so had this evening a bit of time to start preparing the filament raw supply for the 4-65A.
This will be a heavyweight amplifier. Too much iron, but 100% DHT and no capacitor in the signal path, a promising design.
A couple of hours were sufficient to prepare some of the key components: a pair of common-mode chokes winded on ferrite rings, capacitor arrays and a Schottky bridge mounted on an aluminium sink:
The raw filament supply circuit follows the standard design recommended by Rod Coleman to use the filament regulator boards. I managed to get a nice pair of 10mH@3.5A chokes made by JMS transformers which is the same company that provides the custom-made split bobbin transformers:
The 10mH choke will help reducing the current pulses and the input capacitance, which is less than 3mF. This circuit will provide 12V @ 3.5A with a ripple current of 31mV peak to peak maximum.
Ale the r2/r3 increse te conduction angle and lower the current pulse of input caps 😉
btw thanks for share all your great work ! have happy new year
manu
Hi Manu,
R2 and R3 will provide sufficient damp to improve impulse response, etc. Also will limit the pulse currents in addition to the secondary winding resistance. What are you suggesting?
Thanks for your comments and hope you have a great new year too!
Ale
I wonder, if you make a interchange:
R2 L1, and R3 between C3 and C7?
what size ripple peak to peak?
Thanks.
Should simulate again, but so far I built it without R2 and R3 and the output voltage is 12.2V at full load which is more than acceptable.