I don't have the 3600, but most tuners feed the LNB power and DiSEqC commands through a choke. This is an easy part to blow if the coax gets shorted somehow, like making or breaking connections when the 3600 is already on. A choke might not be that hard to replace. However you need LNB power for DiSEqC devices, so unless you put a scope on the jack, I'm not sure one can conclude the DiSEqC output is dead. That expands the possible problem set unfortunately to DC voltage converters, etc.