Re: Valour of capacitors and diodes in circuit with 7660s

Posted by Gabi Smith on Apr 25, 2018; 8:19pm
URL: http://guitar-fx-layouts.238.s1.nabble.com/Valour-of-capacitors-and-diodes-in-circuit-with-7660s-tp42786p42795.html

Thank you for the response. I think it will be enough (Only a TDA2040 and a j201 to supply).

The1uf is given for the inversion (positive to negative). Nothing is said about the capacitors needed to doubling the voltage. I've seen on the internet that the common valours given in this case is 10UF for the one coming from the second pin of the chip and 100uf for those who are going to the ground.

On the breadboard, i've got the figure 8 (+/-9v for the tda2040 power amp and 18v for the j201 pramp), but i'm meeting a bug : a tremolo effect coming I think from an oscillation of the invertor. The multimetter is alternating -2, -3. and -6v and never show -9v. The 18V seems ok (17.6V for the supplied 9.5V). There-s a high treble hiss too. Soooo, a little debubugging is waiting me tomorow.