Jean Hiraga SE Amplifier Power Supply

[Nikon1975]

Dear All,

I would like to build the SE ampli based on KT88 from Jean Hiraga. I am king of new of the business, but it looks to me that there is something wrong in the design of the power supply:

1) The specs of the rectifier impose a maximum capacitor after the tube of 33uF, while in the design there is a 100uF capacitor.

2) If I simulate the power supply with PSU 2, imposing a load of 200 mA there is no way I get the 375 V required.

I am not an expert, I was wondering if some of you built this amplifier, and if you had problem in the power supply.

Best Regards,

Davide

 

[Gordy]

Please consider posting the schematic, or a link to the schematic.

: )

 

[Nikon1975]

Sorry, that's the schematic: Jean Hiraga 12AX7 Single Ended KT88 Tube Amplifier Schematic

thanks,

Davide

 

[nicoch58]

look like is dual mono psu , as there is a 100ma on kt88 and the choke is rated 150ma....

not expert I need to learning how design a tube psu , but 100µ is too big, and small value is better as low peak current ,to lower the ripple better add second filter stage...

the reflect impedence/resistence of trafo is important, to avoid ringind and overshoot and tube want to see a min resistence from trafo (tribute-audio trafo a in 700 ohm range)
the choke resistence play for final voltage...look like is better usa last filter with R to separate the channel and set the rigth B+

 

[nicoch58]

here the view of Dht Rob
Google Traduttore

more info here
http://www.freewebs.com/valvewizard/fullwave.html

 

[Bas Horneman]

Dht Rob's article translated by moi.

http://www.dhtrob.com/overige/pdf/dhtrob_psu.pdf