Assembly Instructions

Disclaimer:
Working with high voltages (110V/220V) can be lethal. Work at your own risk. Soldering irons are hot. Use caution.

Tools Required:

1. Cutter Pliers
2. Long Nose Pliers
3. Soldering iron (adjustable temperature preferred), or 25-30W soldering iron. (Do not use 100W soldering iron.)
4. Solder lead (60/40 or equivalent)

Step-by-Step Assembly Instructions:

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TIP:

1. Solder components from the smallest/shortest to the biggest/tallest component in that order. This makes assembly easier.

2. Do not use too much solder lead. Use just enough to make a good connection. The PCB is plated-through hole, and molten solder lead will flow into the hole to ensure a good connection. You don't need globs of solder to make a good connection.

3. Work slowly and carefully, especially if this is your first time. Double-check parts before soldering them. It's easier to solder something in, that to desolder them out (if you make a mistake).

4. If you make a mistake solder a part in the PCB (example, wrong location, or wrong orientation/placement), you will need a desoldering tool to suck the solder out from the board.  Even then, the part may not easily get out. The easiest thing to do is to "sacrifice" the part, cut the leads, use a long nose pliers to hold the lead, heat the pad while pulling the leads out. Then use a desoldering tool to open the hole. So as I said, double check parts before committing to solder them.

Step 1:

Solder all resistors, and diodes to the board.

(2pcs) 220 ohms - RED-RED-BROWN

(1pc) 8.2K (8K2) - GRY-RED-RED

(1pc) 7.5K (7K5) - VIOLET-GRN-RED   = this is marked on the PCB as 7.68K

Note the orientation of the (4) diodes on the board. The white band should all be on top.

Step 2:

Next, solder the 0.1uf capacitor. You may need to open up the legs of the capacitors a bit to fit in the holes.

They'll go into the PCB looking like this.

Step 3:

Next, solder the bridge rectifier W02G. Note the orientation of the component and where the flat side is pointing.

Step 4:

Next, solder the (4) electrolytic capacitors. (2pcs) of 10uf and (2pcs) of 1uf.  You will need to open up the legs of the 1uf a little bit to go into the hole.

This is what your PCB board should look like at this point of the assembly. Note the capacitors.

Step 5:

Next, solder the (2) LM317 regulators to the board. For aesthetics, make sure they're the same height when you solder them. Also, note the orientation. The flat side (heatsink mounting part) should be facing towards the outside of the PCB.

Step 6:

The only thing remaining to do now is solder the (2) big electrolytic capacitors.

TIP: The capacitors are snap-in type. So when you put place them on the PCB, do a twisting motion. When you solder the capacitor, the (-) leg of the capacitor is tied to the ground plane of the PCB. The PCB copper can suck the heat out of your soldering iron. So make sure to bump up the temperature of your soldering iron up.

TESTING:

Solder AC1 and AC2 terminals of the board to the SECONDARY windings of your power transformer. Apply power to your power transformer, and measure that you're getting 44V and 48V DC at the output of the PSU board.

Note: You may not measure EXACTLY get 44 and 48V due to component tolerances. But if it's of by a few millivolts, you'd be fine. If you're measuring something like 0V or 60V or higher, something is wrong and most probably you have a short somewhere.

If everything checks out, then attach a heatsink to each voltage regulator. I recommend you use TO-220 insulators/spacers so there is no electrical connection between the heatsink and the regulator. You can also use TWO SEPARATE heatsinks, one for each regulator. Just make sure the two heatsinks DO NOT touch each other.

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