DIY Mic Pre Kits, Lunchbox Mic Preamp Kits, Power Supply Kits

I built prototype #003 and #004.

I am now 95% satisfied with this PSU.

Accomplishments: Prototype #004 is:

1. Now using less components. Was able to eliminate the expensive 0.1 ohm Resistor. And there's 3 of them in prototype #002.

2. Finalized values for the inductors for 100% reliable startup of the PSU. Even just a 1milliHenry difference in inductor values spell the difference between reliable startup operation, or not working at alll.

3. Reduced the number of 2.2nf caps from 6 pcs to 4 pcs.

4. Reduced, almost negligible vibration noise coming from the inverting section.

5. When connected to the SC-1 pre and mini-IO module, it is very quiet! No crackling sound, no RF noise caused by the PSU.

6. Add (3) 0.1uf bypass capacitors. One for the +48V section, +18V and -18V section


So now, I just need to modify the PCB design one last time to incorporate the above changes. Maybe one last final final prototype PCB...

Then we're good to go... then I'll be able to sell SC-1 Solo preamps in small cases.

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