sir tony namisslook nyo ata... full wave voltage doubler yong input nya.
there is a mistake in the drawing, C1 and C2 is just 1 cap and connects to the + and - terminals of the bridged diodes....16volts ac input means an unloaded rail of 22.4 volts, as it is, zener current is about 22mA without anything connected to the psu terminals, actually less if we consider the dc resistance of hte power traffo...D3,R4,Q1 can be replaced with just a single 5watt zener diode.....
In this voltage doubler by ESP, D2 and D4 are useless. They should be removed. Once removed the circuit becomes what Tito Tony presented. Looks like ESP missed that...
ah ok.. baka kako namisslook lang ni sir tony kaya nya nasabi nyang mali yong caps
good advise......napasin ko ang title ng thread ay "First Watt B1 buffer preamp" i know this was a Nelson Pass design so this is the proper link: http://www.enjoythemusic.com/diy/0708/first_watt_b1_preamplifier.htmand scheme:
The human side of Born2BeWired talking... hmm you have a carbon-based side after all.
The stock parts are 2SK170's, LSK170's or 2SK370's, and you can use substitutes having Idss between than 5 and 10 milli-Amps and transconductance numbers from 5 to 30 milli-Siemens.
Another thing i find interesting with the pass circuit is the hefty capacitance he used with the bias provider: 15000uF. This, in combination with the 10k + 10k voltage divider resistor, will result in an rc time constant of 75 secs! (5000 x 15000e-6)Simply put, the circuit will require about 2minutes from turn on for the bias to settle to its design value. Its like waiting for a windows pc to boot before you can use it to its full. But this wont probably matter if used with valves amp, as it will take roughly the same amount of time to cold start these amps.