Re: [Elecraft] K3 SSB + CW Power Overshoot
> Changing back to SSB +CW What is SSB +CW? 73, Jim K9YC _ Jim: SSB +CW is a mode/configuration whereby one can send CW when in the SSB mode. The CW frequency is offset from the SSB carrier frequency by the value of the selected CW side tone. Purpose: enables means to reply to a SSB communication with CW in poor band conditions. Sometimes termed "cross mode". 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
Re: [Elecraft] K3 SSB + CW Power Overshoot
On 6/16/2018 9:16 AM, Dan Maase via Elecraft wrote: Changing back to SSB +CW What is SSB +CW? 73, Jim K9YC __ 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
Re: [Elecraft] K3 SSB + CW Power Overshoot
The K3 SSB + CW Power Overshoot behavior has been passed up the Elecraft Tech/Engineering chain. I expect it may take them some time to get to it, so in the meantime it would be useful for those interested to conduct the test below to determine if the behavior is unique to my K3 or more wide spread. My primary concern is operating with the K3 driving an amplifier (KPA 500 in my case). It is often the case that the overshoot is so high that the KPA faults on the first key press when power is set for 500 watts and in SSB +CW mode. __ Following is a repeatable test that exhibits the overshoot and power adjust instability problem we have been discussing. Setup: 1, Output terminated in dummy load (ANT 1) 2. Config: CW WGHT -- [1] SSB +CW 3. S Meter Peak -- ON 4. Meter Mode -- SWR/RF (to observe output power) 5. Set Power 50 watts (initial setting) 6. Select any band Operation: 1. Select CW mode; VOX on Press key and hold. Note that power ramps up to the set 50 watt value Adjust power up or down; note that the power change is smooth with no jumps or overshoots Press key on/off/on -- power always returns to set value Release key and set power to 50 watts 2. Change to SSB mode (upper or lower) Press key and hold while observing watt meter -- note that power overshoots the 50 watt level and then drops to 50 watts. Adjust power up. Note that the power jumps high then returns to set value. Adjust power down. Note that the power jumps high, than returns to set value. (note that whether the power is adjusted higher or lower, the output power jumps higher, then reduces to the set value). Also note that the power supply current jumps (overshoots high) coincident with each power adjustment. Release key, then press again and hold. Note that the power does not overshoot the set value. Release and hold any number of times and power continues to be stable at set value. Changing now to CW mode with VOX and power is stable. Changing back to SSB +CW and power is unstable and with overshoot with first key press. This phenomenon occurs in both HP and LP modes. This phenomenon is apparent when the K3 is initially turned on from a cold start, but gets progressively more pronounced after about 10 minutes of on time in quiescent state (no RF out). PA Temp at this time is 25C. As requested, fan is set to level 1. Discussion: It is my understanding from old Reflector mail posts that the SSB +CW mode is implemented such that when key is pressed, the K3 changes dynamically from SSB to CW mode. It appears that the CW ALC function is not in play until some time delay after key press, at which time the CW output settles at the set power level. This time delay would appear to be at the root of the problem. When the power is adjusted, it would appear the ALC loop opens up and then re-engages when adjustment stops. The fact that the phenomenon changes in magnitude as the K3 warms up, may simply be a function of linear stages within the ALC loop changing gain with temperature. The above test sequence is easy to apply and as such would be very curious to see if the phenomenon occurs on any of the Elecraft bench test K3's. __ Thanks and 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
Re: [Elecraft] K3 SSB +CW Power Overshoot
An afternoon of operating SSB a bit and the CW overshoot behavior has returned. No joy. Hope this gets on the Elecraft bug list. 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
Re: [Elecraft] K3 SSB +CW Power Overshoot
Bill: Thanks for your input. I did EEINIT yesterday and reloaded all SW. No change. Today, I did EEINIT again and fooled around with the radio in its native state, changing modes, etc. Then reloaded saved configuration and for no particular reason, did a BSET. Then did a SSB +CW selection. Lo and behold, the CW behavior is what I would expect and same as in basic CW mode. No overshoot and power change is smooth with no jumps. On CW key press, power starts out slightly low and builds to the set value. I suspect there is a bug in the code somewhere. Experience says there is probably an uninitialized variable lurking in the ALC code. **Elecraft SW developers note.** It will be interesting to see if this good behavior sticks. BTW, Albuquerque is my old, old stomping ground. BSEE from UNM in 1967. 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
Re: [Elecraft] K3 SSB +CW Power Overshoot
Interesting! Sounds useful on 6m, for example, when running a contest SSB above 125 and there's a difficult Q where the guy's having trouble with an exchange element. Generally running an amp, so overshoot would be a problem. Thanks for info. 73 Josh W6XU Sent from my mobile device > On May 28, 2018, at 11:41 AM, Dan Maase wrote: > > > Josh: > > This configuration permits sending SSB as well as CW in one mode (SSB). CW > frequency is offset from SSB frequency by the value of configured CW tone? > This is sometimes called "cross-mode" in non-Elecraft nomenclature. > Useful to continue a SSB conversation of QSB reduces intelligibility. > Also can check configured power with a key press without messing with "Tune" > setting. > > 73, > Dan > AC6DM > > What is "SSB+CW mode"? > > 73, > Josh W6XU > > Sent from my mobile device > > > On May 28, 2018, at 9:44 AM, Dan Maase via Elecraft > > wrote: > > > > > > 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
Re: [Elecraft] K3 SSB +CW Power Overshoot
What is "SSB+CW mode"? 73, Josh W6XU Sent from my mobile device > On May 28, 2018, at 9:44 AM, Dan Maase via Elecraft > wrote: > > > 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 j...@voodoolab.com __ 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
Re: [Elecraft] K3 SSB +CW Power Overshoot
Dan, I experienced a similar issue with my K3, S/N range 4,000. I attempted a TX Gain calibration with minimal improvement. 40m and higher bands (in frequency) worked OK (no overshoot) while lower bands still faulted. I finally performed an EE INIT, reloaded 5.60 firmware, and the last saved configuration. I later upgraded to the beta 5.64 firmware. Neither firmware version resulted in overshoot after the EE INIT. The rig has operated normally over the last week. I can now rest without worries (about the K3 and its performance at the upcoming FD). Save your current K3 configuration and try an EE INIT. While not logical, I did this twice before I achieved success. GL! 73, Bill, K8TE -- Sent from: http://elecraft.365791.n2.nabble.com/ __ 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
Re: [Elecraft] K3 SSB +CW Power Overshoot
Josh: This configuration permits sending SSB as well as CW in one mode (SSB). CW frequency is offset from SSB frequency by the value of configured CW tone? This is sometimes called "cross-mode" in non-Elecraft nomenclature. Useful to continue a SSB conversation of QSB reduces intelligibility. Also can check configured power with a key press without messing with "Tune" setting. 73, Dan AC6DM What is "SSB+CW mode"? 73, Josh W6XU Sent from my mobile device > On May 28, 2018, at 9:44 AM, Dan Maase via Elecraft > wrote: > > > 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