Electronic Bench Power Station

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This is my electronic bench power station........ you may have seen it in the background of this project Retractable Resistor Rack

My original intention with this was just to use an old PC case (check) and a PC power supply (check) to provide a simple way of getting the voltages from the power supply to the front panel (check but with a slight bit of madness). As I used it, it's functionality changed (scope creep, many checks).

Current Functions:

1. Provide regulated -5, 3, +5, +12, eventually -12 volts for my electronic breadboarding projects.

2. Keep it simple, it has gotten a bit complex.

Added functions:

1. +6, +12 unregulated volts.

2. 4 AC outlets in a single 2 gang box

3. Oscope stand.

4. Bench Lamp support.

There a few things I would do differently but my main goal was to be able to keep the case as fancy as it is and be able to swap out the power supply if needed very easily.

STEP 1: Regulated Voltages From PC Power Supply

As you can see from the picture showing the back of the PC case, I did not use a standard PC power supply by todays standards. I bought this PC power supply many years ago, (pre 2000). I actually bought 2 for the sole purpose of using it in this fashion. I however did not save an old PC case from back then. So I hacked up the back of the case to mount this power supply.

The red button near the bottom of the case is to turn the power supply on and off. I cut a standard PC power cord and it is hard connected to the AC power inside a 2 gang AC outlet box, which I mounted to the front of the PC case.

As you look inside the case you can see that I used 2 pin molex connectors replacing the (antiquated in this PC power supply) connectors that came with the power supply. The idea here is to use the same connectors that come with the power supply so that you do not have to open or alter the power supply itself.

STEP 2: Getting Usable Voltages to Front Panel.

I used speaker connectors as a way to make quick connections to my supply voltages. For the 3, -/+ 5, and + 12 volts I did the following.

I connected all the black connectors together and I use those as the ground. As You look at the -5 you will see the red is the -5 voltage and is flipped compared to the other 4.

The bottom 2 connectors are wired together but go directly to a 2 pin molex connector that connects with it's mate for the appropriate supply voltage

The other 4 connectors are wired to each other and go to a switch mounted above the connectors. Then the other connector of the switch goes to the appropriate power supply voltage.

I used crimp connectors to connect the wires to the switches, just in case I decide I want to change the switches. Sure if I use different switches that require a different mounting hole I'll have to figure out that if I decide to do so.

I did cut a PC perfboard to help get the connectors on the speaker connectors to solder to. This was done more for structural reasons the solder tabs on these speaker connectors are very flimsy.

STEP 3: 6 and 12 Volt Unregulated Supply Voltages

I eventually decided to add an unregulated 12 volts to this supply center. After spending a couple of nights thinking how I wanted to do it, here is what I came up with.

I took a 12 volt 1 amp battery trickle charger and opened it up. I removed the switch to select either 6 or 12 volts from the original PC board inside the unit. I sourced some 1 amp diodes rated for 12 volts and made another bridge rectifier using the 6 volt output leads from the transformer. This gave me both 6 and 12 volts at the same time.

I used a 2 pair speaker connector as the front panel connections to use these supply voltages

I also put an AC switch on the front panel to control AC voltage to the charger unit. To use this unit it does have it's own AC cord that plugs into it's own outlet.

STEP 4: Shelf

I added (bolted really) a piece of wood to the top of the PC case so I can place an OScope on top of the power supply station. If you do this I recommend you do it first, but if you already have your PC power supply mounted in your case, you will want to either remove it, or make sure you place something on top of it to keep the metal from the holes you drill for the bolts from getting into the PC power supply.

STEP 5: A Bit of Light

This is a simple LED strip lighting that I hot glued to a PVC pipe I cut in half longways. It uses it's own power supply which I plug into a manual AC outlet I did an instructable for. Manual AC Power Controller