I just received a contract to build a 300b stereo amp. Actual going to build two, keeping the second one for myself, and drive it from my existing desktop amp. My client intending to drive it from her Sansui 7070db stereo receiver.
I was never going to do a 300b build, but she buys all the parts for me.
Fine, I show others how I do the filaments......
I was never going to do a 300b build, but she buys all the parts for me.
Fine, I show others how I do the filaments......
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LT specifies 150uF as an output capacitor for the LT1085, not 100uF. It likely wont matter, but be mindful that the 1085 can get unstable without proper decoupling.
Look up the ripple current rating for the first capacitor, rookie mistake is to take anything less than 2A of ripple current rating.
decoupling the adjust pin of the 1085 can lower noise by 3..9dB but requires an extra diode over the Adjust-output pins.
Look up the ripple current rating for the first capacitor, rookie mistake is to take anything less than 2A of ripple current rating.
decoupling the adjust pin of the 1085 can lower noise by 3..9dB but requires an extra diode over the Adjust-output pins.
I strongly recommend Rod Coleman's filament regs. They've been evolving since around 2012 and I think in V7 now. Very widely used in several countries, available with instructions and backup from Lyrima in the UK. I know of nothing better and plenty of designs which don't sound as good. Good value too.