The BA-3 as preamp build guide

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Zen Mod

Zen Mod

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I believe everything should be clear if you read datasheet of xformer

having separate secondaries and connecting them to have CT is much easier that the other way around

here's some help

ignore miss-type here and there

if you have datasheet, post it here
 

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Zen Mod

Zen Mod

Official Court Jester
Joined 2003
zenmod.in.rs/
Paid Member
duh

no color info there

what wire colors you have , one secondary, second secondary?

usually, start of winding is one color, end of winding other color

say that you have green and yellow


green 1 : first secondary out (to diode bridge)

yellow 1 + green 2 : Center Tap (GND)

yellow 2 : second secondary out (to diode bridge)

checking is easy , by sketch I uploaded ; connect two wires from different secondaries, put Vac meter across free ends,power up Donut ( taking all safety measures - isolated mains contacts etc.), measure ; if you have double Vac , that's the arrangement ; if you have nearly 0Vac , change place of wires of one secondary, retest
 
T

Tomcat1969

Member
Joined 2019
Zen Mod said:
duh

no color info there

what wire colors you have , one secondary, second secondary?

usually, start of winding is one color, end of winding other color

say that you have green and yellow


green 1 : first secondary out (to diode bridge)

yellow 1 + green 2 : Center Tap (GND)

yellow 2 : second secondary out (to diode bridge)

checking is easy , by sketch I uploaded ; connect two wires from different secondaries, put Vac meter across free ends,power up Donut ( taking all safety measures - isolated mains contacts etc.), measure ; if you have double Vac , that's the arrangement ; if you have nearly 0Vac , change place of wires of one secondary, retest
Click to expand...

I understand. Thank you.
 
M

McQuaide

Member
Joined 2011
sov said:
😀
They are ClarityCap CSA bought at HiFiCollective.
Click to expand...

I went ahead and put these caps on the outputs of both my Pearl 2 and BA-3 FE, replacing the electrolytics and film bypass. 2.2 uF is all I need based on input impedances. I listened for a few minutes and my initial impression is positive, I'll try to do a longer session tonight.

Don't laugh at my BA-3, I mistakenly bought components that are oversize and crammed them in. :p

y4mFAGxsbRi55GAX6rrTM0mTQ7wrmPcnanYfTzTtKQroBJGpreOwQZHSyXvFDGLc0ILobI9mw6HjSnlX0rPuUMw1R2rrYrb-Y0f2MinQmgOUKn6CUSY59C7hHiED_qyC2StuqzCI7Cy69NrWYFS4qMRWpiHEYuIB2Ixlyf4YegPZrDvt-7LVm7r-T4wI2gEdVfuQZ2xaOrL2JQCPRfWvN7Dfw
 
M

McQuaide

Member
Joined 2011
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