PSU-2448mk2 Power Supply Kit
2. The SC-1mk3 and X-12 preamp have on-board, local voltage regulators. The local regulators adjust the voltage down to
+/-18V on the preamp board. So we want to feed the SC-1mk3 or X-12 board with at least +/-20V coming from the PSU.
PSU-2448mk2 Short-Circuit Protection
The PSU-2448 Power Supply kit uses LM317 and LM337 Voltage regulators. These voltage regulator chips have built-in short-
circuit protection.
However, in some cases, the built-in protection of the voltage regulator isn’t enough. Thus, when a short circuit happens (say
the V+, or +48V is accidentally shorted to GND), the voltage regulator may fail. A common symptom of a failed voltage
regulator is it won’t adjust no matter how you turn the trimmers, or it would only output a small voltage.
The fix is removing the faulty voltage regulator and installing a brand new one. The desoldering of the faulty regulator is a little
di
ffi
cult if you don’t have the proper desoldering tool.
To solve this problem, the new PSU-2448mk2 Power Supply Kit (Black face PCB) has (3) on-board fuses to protect the PSU (and
your equipment) from accidental voltage shorts.
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