frequal.com

Assemble Dead Photobridges Into Working Ones

If you have several PhotoBridges that no longer work properly, there is a good chance you can take parts from one and fix another. A dead PhotoBridge has roughly even chances of having a dead mainboard or a dead power supplies. Moving a working power supply into a system with a dead power supply will often restore it to life.

Disclaimer

The process below involves testing voltages and disassembling electronics that weren't intended for consumer modification. If you haven't worked on electronics before, or if you have any doubts, please consult with someone who does or take your Photobridges to an electronic repair shop.

Also, this will void your warranty, but since the last one was sold new over a decade ago, I think they are all out of warranty anyhow.

Supplies

You will need:

Multimeter (I used this one from Harbor Freight, a steal at $6.39)
Philips head screwdriver (magnetic tip is helpful but not required)
Sharp knife or box cutter
Small container for screws

Step 0: Start Your Notes

Once you start disassembling your Photobridges, it can become hard to keep track of them. I recommend making notes or a spreadsheet to track the serial number, the power supply status, and the mainboard status. Keep track as you go.

Step 1: Locate the working power supplies

Open your first dead Photobridge. Remove the 7 screws (3 on back, 4 on bottom). Slice the warranty sticker. Slide off the top case and set it aside.

Plug in your opened PhotoBridge, being careful that nothing can fall in or accidentally make contact with the exposed electronics.

First, inspect the small LED on the power supply close to the from of the PhotoBridge. If it doesn't light up at all, the power supply is likely dead. Even if it lights up, you'll want to test the actual output &em; I've seen power supplies where the LED is lit but the output is too low.

Next, find the connector where the power supply connects to the mainboard. The connector has thick metal posts that bend at a 90 degree angle and go down to the mainboard. Sil-screened onto the mainboard are the voltages: 3.3, 3.3, Ground, Ground, Ground, 5. Turn on your multimeter and touch the black lead to a ground wire, and the red lead to one of the 3.3V wires. The multimeter reading should be close to 3.3V. I've seen Seen them as low as 3.17 and as high as 3.3. Repeat for the other 3.3V line, then the 5V line. 5V should be close to 5V, mine were between 5 and 5.14.

If the power supply voltages check out, then the mainboard is bad.

Record your findings in your notes and move on.

Step 2: Remove the dead power supplies

Power supplies are held in place by 4 screws in the corners, one ground wire screw, and the mainboard connector. For each dead power supply, remove the screws and wiggle it slightly loose, so you can move it about an inch away from the mainboard. This will give you room to pull off the connector. Grab the connector firmly and wiggle it out carefully. It is pretty snug. Take the dead power supply and set it aside for electronics recycling. I like to mark it DEAD with a permanent marker so I can't get confused later.

Step 3: Test unknown motherboards with a working power supply

Now find one of the working power supplies (with a bad mainboard) and remove it, following the process from Step 2. Place the supply in a PhotoBridge where you removed a dead power supply. First, hook up the connector to the mainboard. Then slide the power supply into place, screw on the ground wire, and attach the power supply with enough screws to keep it from moving. I found just 1 toward the front of the case was enough. Plug in the PhotoBridge and attach a video cable to a TV or monitor. See if it comes to life! If so, this mainboard is good, and you have successfully assembled a new working PhotoBridge, congratulations! If not the mainboard is dead. Either way, record your findings.

If you have several PhotoBridges to test, take out the power supply and test the next one.

Step 4: Assemble Working PhotoBridges

When you are finished testing all of the mainboards, you can take all of the working power supplies and pair them with working mainboards. This time, fully attach the power supplies to the case with 5 screws. Put the top cases back on, and reattach with the 7 screws you took off originally.

Enjoy your new PhotoBridges!

Extra Note: Maintenance

Photobridges seem to suffer more failures the longer they are powered on. I recommend you unplug Photobridges when not in use to maximize their useful lifetimes. You may want to invest in an inexpensive power strip to make this easier.

Last modified on 29 Jul 2020 by AO