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Figure 2 - Identifying the connection point
Figure 2 - Identifying the connection point

The viewfinder will be powered by the camera's main circuit board, and normally only requires a single DC voltage between 9 and 12 volts to operate. The viewfinder will also have a video input and ground line, as well as several other functions such as a power LED or function switch that can be ignored. In the end, you will only need three of the wires coming from the viewfinder (power, ground, and video input). Start by removing the multitude of tiny screws from the camcorder shell until you reveal the main board where the viewfinder connects as shown in Figure 2.

Normally, the viewfinder will have a removable plug that can be pulled right out of the main board, making it easier to probe for voltage if necessary. Having removed many of these viewfinders, I can assure you that there is no standard whatsoever when it comes to number of wires, or wiring colors. Black and Red almost always do not indicate positive and negative, so a little hardware hacking will likely be needed in order to get the viewfinder to power up and run without the rest of the camera.

If your viewfinder is soldered directly to the board, cut the wires so there is a bit of wire left on the main board in case you need to power up the camera to aid you in finding the power and ground lines later. If all the wires are the same color (often the case), then find some small labels to stick on the wires, or make a diagram of each wire so you can match it back up to the viewfinder.



Figure 3 - Live testing to decode the viewfinder wiring
Figure 3 - Live testing to decode the viewfinder wiring

Figure 3 shows one of the many alternative methods that you can use to help identify the positive (power) and negative (ground) wires of your viewfinder - by checking every wire on the main board while the camera is powered on. This can be done with or without the viewfinder connected, as most cameras will still power up with it disconnected from the main board. Figure 3 (inset) shows how my connector looked, having four white wires and one blue wire. Again, there is almost always no logic to the colors or even the number of wires, many of which are totally redundant.

Viewfinder voltages range from 6 volts to 12 volts, and will often run fine from any voltage between 9 and 12 volts due to the built in regulation, which make them easy to connect to an external battery source. Figure 3 shows my multimeter registering 12 volts, but negative, meaning that I have the correct two power wires, but they are reversed according to the colors of the jacks on my meter. Sometimes you have to test every possible combination of wires to get a voltage reading, but if your camera is powered up and fine without the viewfinder connected, then you will eventually find the magic pair. If you have a dead camera, or one that does not like operating with the viewfinder out of the circuit, then there are several other ways to decode the cryptic viewfinder wiring.

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