🛠 ПАЯЕМ САМИ KIT DIY НАБОР БЛОК ПИТАНИЯ 1,5-12В LM317 С АЛИЭКСПРЕСС

DIY LM317 adjustable power-supply kit (1.5–12 V) — Assembly walkthrough, test and review

What the kit includes

• Toroidal or boxed mains transformer (220 V primary → 12 V secondary), transparent plastic case, and mains lead.
• Single-sided PCB with full silkscreen (component outlines and labels).
• LM317 regulator (TO-220), IC socket, heatsink, mounting bolts; thermal paste recommended.
• Voltmeter module and front-panel knob.
• LEDs (blue, yellow, red, green) and buzzer.
• Potentiometer, trimmer, assorted resistors (unmarked), diodes, transistor, electrolytic and ceramic capacitors.
• Alligator clips, wiring, screws, spacers, heat-shrink tubing, and an English instruction leaflet.
• Packaging: components bag and separate front panel.

Assembly / tutorial highlights

1. Pre-fit components before soldering. Because resistors are unmarked, measure their values with a multimeter first and place capacitors/LEDs with correct polarity.
2. Install diodes, transistor and ceramic capacitors (ceramics have no polarity). Fit the IC socket keyed correctly on the PCB.
3. Mount the LM317 to the heatsink using thermal paste and the supplied bolts.
4. Install the potentiometer and trim pot on the PCB/front panel.
5. Voltmeter module: desolder or cut its wires and solder the three legs directly to the PCB; secure the module with a nut/bolt.
6. Solder the transformer secondary leads to the designated PCB pads. Use spacers so the PCB does not touch the case.
7. Assemble the case and front panel, attach the knob, and connect the alligator-clip wiring.

Tools used (examples):

• Temperature-controlled soldering iron, flux/solder, heat-resistant mat, third hand, multimeter.

Note: the PCB silkscreen and the English leaflet are helpful during assembly, but resistors are not pre-marked—plan to ring out values before soldering.

Testing, behavior and faults observed

• First power-up: no smoke and the voltmeter module powered, but the front-panel voltmeter and an external multimeter showed discrepancies. The difference was larger at low setpoints and decreased at higher voltages.
• Output range: adjustable from low voltages up to roughly 14+ V no-load, despite the kit nominal range of 1.5–12 V. Readings became unstable (“dance”) near the maximum setting; applying a load can sometimes stabilize the reading.
• Short-circuit protection operated correctly: the supply shuts down on a short.
• Current capability is limited by the LM317 variant used — roughly 1.5 A max. Suitable for light bench work, not high-current applications.
• PCB connectors:
  1. Main output +
  2. Main output −
  3. Buzzer / continuity-check trigger
  4. Pulse-generator output (adjustable with trim pot)
  5. Unspecified function
• User error observed: applying a positive lead to the pulse output (instead of the main output) damaged the board’s microcircuit/module. Consequences included two outer LEDs ceasing to light and the maximum output being limited to about 4 V. The author plans to replace the microcircuit.
• Mechanical/fit notes: case fit and mechanical quality were praised.

Conclusions / review points

• Strengths:
  • Good beginner-friendly kit for learning soldering and basic PSU circuitry.
  • Attractive case and clear PCB layout.
  • Useful front-panel features: adjustable output, built-in voltmeter, LED indicators, buzzer/continuity, and a pulse-generator output.
• Limitations:
  • Low current capability (≈1.5 A).
  • Voltmeter module inaccuracies and discrepancies versus an external multimeter.
  • Instability at maximum settings (readings may “dance” without load).
  • The microcontroller/module on the meter/panel is fragile and can be damaged by incorrect wiring.
• Recommendation: Suitable for hobbyists and novices if you follow wiring carefully and understand connector functions. Replacement parts and tools are commonly available (author links some in the video description).

Main speaker / source

• The video author / channel host — a DIY electronics reviewer and assembler.