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PSU-1848 Power Supply Kit
PSU-1848/2448 Wiring Guide
1. Connect AC1, AC2 and CT pads of the PCB to the secondary windings of your power transformer.
2. Connect the (+), (-) and GND to your SC-1 Preamp, or project.
3. Connect the +48V pad to your SC-1 48V pad.
Note
: Before connecting the power supply outputs directly to your project, measure the output voltages first and adjust if
necessary. See the section Voltage Adjustment Guide below.
PSU-1848/2448 Voltage Adjustment Guide
When calibrating/adjusting the output voltage of the PSU-1848/2448, make sure there is a "load" connected to the PSU board.
Otherwise, you may get a false reading when turning the trimmer pot.
The simplest way to do this is to just solder the (2) on-board LEDS on the PSU-1848 board.
1. Using a voltmeter, measure the voltage across the (+48) and GND terminals. We want a voltage reading of +48Volts if you’re
using this for the SC-1 Mic Preamp project. You probably won’t exactly get 48Volts, so using a small screwdriver, adjust
leftmost trimmer R3 to measure 48 volts at the outputs. Turn the screwhead
COUNTERCLOCKWISE
to
increase
the voltage.
2. Next measure the voltage across (+) and GND pads. Adjust the middle trimmer R6 to get +18V at the outputs. Turn the
screwhead COUNTERCLOCKWISE to Increase the voltage
3. Next measure the voltage across (-) and GND pads. Adjust the rightmost trimmer R7 to get –18V at the outputs. Turn the
screwhead COUNTERCLOCKWISE to Increase the voltage Note... since this is a (-) supply, increasing the voltage will direct you
towards (0) zero volts. You'd want to decrease the voltage (i.e. turn CLOCKWISE) to adjust the voltage to -18Volts.
4. DONE! FINISH! Power off, then connect the (+), (-), GND and +48V pads to your SC-1 preamp or project.
Note: After connecting your preamp/load to the PSU… you may want to re-check the output voltages just to be sure. Re-adjust if
necessary.
