Quark fried, blown capacitor...

Neil, actually, the Quark "fix" is only a partial fix in reality. The are two sets of FETs in the Quark. One set, that is physically sandwiched between the two PCBs only has a rather thin heat spreader attached to it via thermal pad. The only way that heat escapes that set is through the air to the case from the heatspreader and through the traces and connections on the pcb that link to the set of FETs that are on the bottom of the esc. Truly not an ideal design. The mod that everyone is doing just allows a thermal pathway from the bottom set of FETs to the case.

The Compro, on the other hand, is rather robustly built. I really liked the feel of it. It has dual heatsinks and runs very cool. It also has a very substantial feel to it. When handling it, you don't feel as though you're going to break it.

The downside to the Compro is the software. Although I found the programming sequence to be easy enough, there are a couple of quirks. The biggest thing is that when running in a forward direction, the first application of reverse throttle applies the brakes, however; if you apply the brakes, go to neutral and then apply the brakes again (pump the brakes) the esc will go directly into reverse on the second application of the brakes. It does this whether the vehicle is still moving forward or not.

The way around this, is to use the forward only mode, but then you don't have reverse.

The second quirk is that you can't start at a creep with the Compro. Once you apply the throttle and it moves out of the neutral zone, the vehicle starts at a roll. Not real fast, but faster than a creep. It's fine for racing, but for bashing around in rocks and stuff, it might be a PITA.

The "problem" that I had, was that I couldn't program the free wheel option that would allow the motor to coast to a lower speed when I went from say 100% throttle to 20% throttle. Whenever I let off of the throttle, it would immediately brake to slow the vehicle to the speed of the new throttle position. This makes jumping on an off road track nearly impossible without wiping out.

All in all, I think that the Compro is a better controller than the Quark. The Quark is just a bit more user friendly, from an operation standpoint. The Quark is smoother.

[zeropointbug]

Yeah, I'm going to get a simple FET clamp for the Quark made so I don't have to get an expensive case machined first. To see how well it works, and if I am happy with no case and just a clamp w/ heat shrink on the controller.

I am also going to see if I can get my thermal probe for my Eagle tree to work, and see what kind of temps the top set of FET's get to in the Quark, and I know the surface area, plus I know the power throughput... I might be able to make some estimates of esc efficiency?

AAngel: How think is the PCB on the ComPro? THe Quark I think is 1mm thick, nothing much, but then again, it's in a case.