I have just attempted the K3 SSB +CW configuration for the first time. Unfortunately, behavior is not quite as expected; I experience a substantial CW carrier overshoot on first key press and after a subsequent mode change. (Mode change can be a band change or an Operate/Standby change when running with the KPA500).
The overshoot is on the order of 10 to 40% depending on the power level setting. When running the K3 barefoot at 100 watts the overshoot is on the order of 110 watts measured with a W2 in peak reading mode. When running the KPA500 set for 500 watts (approx 27 watts drive), the KPA output overshoot has been observed to exceed 700 watts triggering a high power fault. The only recourse is to reduce drive setting to the KPA500 to an output level of 400 watts or so where the output power overshoots to on the order of 550 watts. Holding down the key after the overshoot, the power settles to the selected value in a second or so (assuming KPA power is set such that no fault occurs). Subsequent CW key presses produce power output at the selected value without overshoot, regardless of momentary or continuous key press. Also observed is difficulty setting power on key down, particularly with the KPA500. Power setting is "jumpy" when changing power, after the overshoot has stabilized. It seems as if when increasing power, it overshoots the set value, then drops to the set value. The issue is observed on all bands and on upper or lower sideband. I've performed TX Power Calibrate several times with reported success, but no change in overshoot behavior. When in normal CW mode, there is no overshoot and the power adjustment is smooth and stable. The SSB +CW mode would be quite useful if it was stable, but I am uneasy using it as currently implemented. Any comments or ideas are welcome. K3 is S/N 4457 Firmware version is 5.62 FPF 1.26 DSP 2.88 73, Dan AC6DM ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
