KH6GRT LAB POWER SUPPLY
OUTPUTS:
+5 VDC (1 TO 6) @ 5 AMPS and +/- 12/15 VDC (1 TO 16) @ 1.5 AMPS
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FRONT PANEL VIEW OF POWER SUPPLY
The 5 VDC supply uses a LM338K adjustable voltage regulator. The +/- 12/15 VDC supply uses a LM317T in the positive side and a LM337T in the negative side.
CUSTOM METER SCALE
FRONT PANEL CONTROLS
The 12/15 VDC and 5 VDC PWR ON switches are in series with the loads. They enable turning the outputs on and off without turning the whole supply on and off. Transformer limitations prevented me from floating both supplies from each other. Both COM jacks are connected together internally.
Labels are Brother P-Touch black on clear backing.
INTERNAL FRONT PANEL VIEW
LEFT SIDE INTERNAL VIEW
The power transformer is from an old S-100 bus computer providing +6 and +/- 15 VDC power. It has high, medium, and low line taps. Only the high and low line taps are selected from the rear panel switch.
An old HP voltmeter was used as the frame for this supply. The voltmeter was gutted and new chassis and perf board mountings were added. A new front panel and remade meter scale completes the metamorphosis.
TOP BOARD INTERNAL VIEW
Mainly the rectifiers, filter capacitors, and protection diodes are here. Most all the leads are going to the voltage regulators mounted on the rear panel heat sinks.
The 5 VDC schottky rectifiers are mounted to the lower frame rail.
RIGHT SIDE INTERNAL VIEW
BOTTOM VIEW
The big U-shapped aluminum piece forms a chassis that the power transformer is mounted to.
REAR PANEL VIEW
INTERNAL VIEW BEHIND THE REAR PANEL