Actually, no ... it isn't the same thing. In the vicinity of their rated dissipation, semiconductors (at least their bulk characteristics) and non-film resistors (solid carbon or wirewound) have a gradual exponential probability of failure with increasing power dissipation. Metal film resistors have a very sharp (high order) exponential probability of failure with increasing power dissipation. As I said before, if you stay below the rated power dissipation of a metal film resistor it will hold up well, but if you exceed that by any significant amount, even briefly, you'll turn it into a blown fuse that will make your rig very unhappy. A semiconductor (again, talking bulk here) and a solid carbon resistor will typically merely degrade under the same level of abuse without catastrophic failure.
Commercially manufacturing such devices taught me a lot. 73, Dave AB7E David Cutter wrote: > Putting several in parallel on a suitable outboard heatsink is not > expensive and, properly rated, will cater for any load. As with > semiconductors, the trick is to not exceed the "junction" > temperature. As always, follow the manufacturer's recommendations > then add your own fiddle factor. MIL 217 taught me a lot. > > David > G3UNA ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
