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X-Can V2 Cooling
I've just finished "cooling" this unit which has been left powered up for the past 4 years. These babies run warm (especially if you live in a warm climate) and the points to watch for are the transistors scorching the PCB and the caps drying out. This doesn't happen overnight but you can imagine what heat the components are subjected to if the unit is left on for years.


The two transistors under the PSU board sometimes scorch both the main board and the underside of the PSU board as there is nowhere for the heat to escape to, it's trapped under the PSU board and over time it will scorch both boards, the solution is as follows:

1: Drill holes in the PSU board. This will allow the heat to transfer up and away from the transistors (make sure you don't drill through any of the tracks, there is plenty of free board to drill but be careful!):

 

2: Fit suitable heatsinks onto the transistors. You will get heatsinks on the two that require heatsinks, namely the two located under the PSU board, you will have to saw the fins off one side of the sinks so they don't "touch" each other... if they touch you'll get a very big "bang" so make sure there is a gap between them. The best heatsinks for this application are from RS components, Part number: 507-4753 36p each. Perfect size but, as mentioned, you'll have to cut the fins off one of them in order that they don't both make contact. The scorching is Perfectly Normal and you'll also find, if you turn the board over, there's the likelihood the tranny pads have lifted off the board due to the heat...... easy to reinforce just scrape back the green from the tracks to expose the copper and then solder on the copper which will reinforce the transistor connections, it's worth doing this "anyway" as the solder will help dissipate the heat from the transistors.

 

3: If you're a paranoid android then you can also vent the enclosure itself, this is not totally necessary as the heatsinks and drilled PSU board will help transfer heat away from the transistors but if you live in an extremely warm climate then enclosure ventilation may also be prudent:

 

4: Replace all of the 85C caps with high temperature 105C types, these are better suited to this application: