@JeffYoung
You probably have an ltspice model. I have a request to You. Could you check what the 100hz ripple will be in this configuration: 33000uF capacitors and 0.47R resistors? Now the ripple is 170mVpp. Rail voltages under load +/- 21.7VDC from 18VAC on secondaries. Maybe it will be better?
You probably have an ltspice model. I have a request to You. Could you check what the 100hz ripple will be in this configuration: 33000uF capacitors and 0.47R resistors? Now the ripple is 170mVpp. Rail voltages under load +/- 21.7VDC from 18VAC on secondaries. Maybe it will be better?
Thank you Jeff 🙂
Do I correctly suspect there will be a bigger voltage drop?
Regards and Happy New Year
Do I correctly suspect there will be a bigger voltage drop?
Regards and Happy New Year
Yes, but not material (~0.05V).
If you're willing to lose some voltage, 1 ohm resistors will nearly halve the ripple again at the loss of about 0.25V.
If you're willing to lose some voltage, 1 ohm resistors will nearly halve the ripple again at the loss of about 0.25V.
I have one more board so I can make a better version without desoldering. I wonder whether to install 4pcs 33000uF capacitors before the resistors and 47000uF on each rail after them . Will it be quieter than all 33mF versions?
More resistance leads to lower-voltage rails and more heat in the resistors.
More capacitance before the resistors puts more of a tax on the transformer (and fuses if you don't have a thermistor or other form of soft-start).
More capacitance after the resistors does too, but to a lesser effect.
More capacitance before the resistors puts more of a tax on the transformer (and fuses if you don't have a thermistor or other form of soft-start).
More capacitance after the resistors does too, but to a lesser effect.
Thank you Jeff.
I was thinking about a slb power supply but the costs will be much higher with a new transformer so I will work on your project 🙂
I was thinking about a slb power supply but the costs will be much higher with a new transformer so I will work on your project 🙂
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If you mean the "Double Bridge" board, they're here:
https://www.diyaudio.com/forums/pass-labs/137145-f3-builders-thread-65.html#post5647859
https://www.diyaudio.com/forums/pass-labs/137145-f3-builders-thread-65.html#post5647859