Eric Lemmon wrote: > I was surprised to notice that, while the > RF output power settings were almost exactly on the money at 5, 12, 25, and > 50 watts into a dummy load, the DC input power to the radio did not track > the output power- not even close! In fact, the DC input power at 5 watts > output was about 85% of the DC input power at 50 watts output. And that is > what toasted the PA module- the DC input power that was not converted into > RF output power was, instead, heating the driver and the PA stages to > destruction.
Something is definitely wrong. I have messed with a lot of power modules and radios and have never seen this type of action without something being spurious. Efficiency of these modules do change with applied drive, and differing control voltages, but not that much. You didn't state exactly what the current draw was at the different levels, so I cannot extrapolate the difference in efficiency of the module at the different power output levels. In your case, however, were not talking about a few percent, like we should be. I'd guess the module was spurious at the lower power levels. Kevin Custer
