enter image description hereI simulated the circuit below with multisim and got the required values.

[![enter image description here][2]][2]

1.25 to 22V using the poistive regulator -1.25V TO -22V using the negative regulator +5V using 7805 -5V using 7905

But when i built the circuit on the bredboard i dont get close to these vakues except the +5V using 7805. The inductor gets very hot and the transformer starts stinking up. Transformer secondary voltage is around 17Vrms.

  • 5
    \$\begingroup\$ Your circuit is shrouded by text boxes and there is no sign of a transformer. Also, there are wire connection dots that don't seem to connect to wires and wires that cross other wires then connect to them - badly drawn circuits are harder to read so please fix it up. \$\endgroup\$ – Andy aka Apr 29 '18 at 19:16
  • \$\begingroup\$ The schematic looks to be completely messed up at bridge D5. First: the AC source is best done as a center-tapped transformer. You can get away not using a center-tap to get your negative rails but that calls for more space than this comment allows. So start off by deleting all of the negative-voltage stuff. Next: move your ground connection from the bottom AC terminal on D5 to the (-) terminal instead. That should get your positive voltage stuff working. We can help you with the negative voltage stuff later. \$\endgroup\$ – Dwayne Reid Mar 2 '19 at 4:24
  • \$\begingroup\$ And C8 and C10 are missing their ground connections. \$\endgroup\$ – Transistor Nov 8 '19 at 23:04

If the transformer stinks this means its temperature is way too high, which means it is delivering way too much current. I assume you haven't connected any loads to your power supply, so it should only draw the idle currents for the regulators, which are a couple tens mA at worst.

Check your wiring for a short somewhere.

Check polarized capacitors are connected with the proper polarity.

Remove voltage regulators and check with continuity tester in diode mode. You should measure a diode threshold or more between each pin. If two pins are shorted together, there's a problem.

Divide and conquer: if the problem persists with voltage regulators removed, then the problem is upstream of the regulators. Then put them back one at a time, and find which one is trouble, then look downstream.


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