Stephen Rector wrote: > The other area is maybe unique to HF digital mode operators. Since > I'm QRP with the KX3, I use Olivia because of it's advantage as a > weak-signal mode. With the KX3, I find that during a 3-5 minute > transmission, the PA starts its HI-TEMP foldback at anything above > the 3.0W setting....
Hi Steve, This is typical. The KX3's heat sink was designed to handle full power only for low to medium duty-cycle modes (CW and SSB) or for shorter transmissions. Olivia is probably worst-case, and I'd expect the maximum to be 3 W or even less. (At 3 watts, the KX3 automatically switches to a higher-impedance PA output, reducing current by about 50% relative to 3.2 watts.) We don't have a larger heatsink planned at this time; you're welcome to roll your own and/or apply some high-performance thermal compound. But there's one other thing you can try: reduce the supply voltage. With a supply voltage of say 9 to 10 volts, you should be able to operate key-down for much longer periods at 5 watts. 73, Wayne N6KR ______________________________________________________________ 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
