Technique - Trying to fix a JVC GY-DV500 videocamera
Swapping motherboards on a JVC-GY-DV500
After a faulty-wired Firewire cable had destroyed the expansion card in the PC and the camera itself was damaged as well, I was facing a dilemma. I still owned footage from multiple miniDV-tapes, but without a FireWire connection, getting them into the PC would be hard, as exactly that connection had failed on my camera. Taking on a repair-attempt seemed like a viable option in such professional equipment.
I decided to look around on Ebay for a substitute GY-DV500. The downside was that I only found US-models. The European models that did come up were defective or were ridiculously pricey.
Why is that a problem? Because the Americans still hold on to the NTSC-standard.
As I expect the FireWire-processing is done on the motherboard, I suspect the models from the US are adapted to their standards and thus can not be exchanged with my European (PAL) PCB.
I eventually found one in Italy for little money. 'Fun' about this lot was the clear damage the camera's housing had sustained. I can only think of a dive towards the ground while on a tripod...
The housing at least showed clear impact-damage at the front and the viewfinders' enclosure was being held together with glue in multiple spots.
Opening up the camera
As I didn't have a service manual at hand from this camera, I also didn't know if there could be components near the FireWire connector that already took the blow instead of the motherboard, so I started opening the unit near said connector.
To get to the PCB with the FireWire connector, a bottom-part of the machine has to be removed, after which the PCB with the first components for power-supply could be pushed aside.
The first consequences
The bottom of the PCB with FireWire connector already showed some first components, connected to ground, that obviously had started to sweat. K601 shows it's running a fever.
I kept my hopes up that this part could already be an explanation, but as this part is most likely just used for interference-supression (as it measures 0 Ohms on the meter) and is connected to ground, I can hardly believe this to be the problem. Let's continue the search for that matter.
With quite a lot of wiring, the FireWire-connection could be traced to the motherboard.
There, unfortunately more damage became visible. Something got really hot here, considering the caps that have nearly desoldered themselves from the PCB and the blackened legs of a large IC. As the PCB-tracks to these legs showed obvious darkening as well, I feared the worst, but kept my hopes up till the last moment.
Damage irreversible
After removing the pink heatsinking slab, this showed what I expected: damage beyond repair.
The burned spot could not be missed, that's for sure.
Totally different motherboards
I started this attempt to exchange either this controller-chip or the complete motherboard with the one from the Italian camera.
This sticker was rather surprising though: it really looked like this camera didn't even feature it's original motherboard, but was used in another type of camera. Multiple parts of the PCB were of a completely different setup than in my 500. The GY-DV300 did exist however, but when it comes to size, it does not look like (At all) that this motherboard would ever fit in it.
The other side of the PCB really did seem to point in the direction of someone else tried to 'fix it'. Multiple components were missing and here and there, some very bad soldering had been done.
I decided not to continue and left the motherboard as it is. No FireWire for me then.