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My QMX+ seems to be working fine but I just did an SWR sweep and something looks bogus. The SWR is approximately correct for the chosen band but it is flat across all of the frequencies with only a little bit of wiggle. I know my 6BTV SWR is all over the map as you move out of the band limits but the SWR sweep does not show it.?
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I have never noticed this before but I kinda don't want to go back one firmware level and lose my calibration. So, I was hoping some of you are running the SSB code and can tell me if your SWR sweeps look OK?
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Thanks,
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Tony
AD0VC
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I just ran a SWR sweep on my QMX+ which is running version 3 of the beta SSB SW.? I am not seeing any change.
Have you verified that the you didn't lose one or more of the BS170s (final power amp)?? Some folks have experienced failure of the BS170s when running the SSB calibration.? I had this issue on my QMX+.? I lost one of the BS170s and had to install replacements.
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Steve KA0SM
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Rig is working normally. Normal power out on all bands. Just the SWR sweeps are flat.
Thanks for looking.
Tony
AD0VC
Example of my 20 meter sweep:
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I just ran a SWR sweep on my QMX+ which is running version 3 of the beta SSB SW.? I am not seeing any change.
Have you verified that the you didn't lose one or more of the BS170s (final power amp)?? Some folks have experienced failure of the BS170s when running the SSB calibration.? I had this issue on my QMX+.? I lost one of the BS170s and had to install replacements.
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Steve KA0SM
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Just ran a SWR sweep on a QMX+ running 1_01_003 into a Cobweb and got this:
It seems to be reporting about correctly, The Cobweb is designed for 20, 17, 21, 24 and 28m.
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Chris, G5CTH
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Thanks Chris, that is pretty much what I expected to see with my 6BTV. It's weird that mine seems to report the correct SWR for the band I select (as compared to my external SWR meter) but it shows it as being the same for all frequencies.? Maybe there is something
in my band configuration settings that is not right.
Tony
AD0VC
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Just ran a SWR sweep on a QMX+ running 1_01_003 into a Cobweb and got this:
It seems to be reporting about correctly, The Cobweb is designed for 20, 17, 21, 24 and 28m.
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Chris, G5CTH
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Hmm. I just watched the external SWR meter during the "sweep" and it holds steady also. It is clearly not actually sweeping for some reason.
Tony
AD0VC
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Thanks Chris, that is pretty much what I expected to see with my 6BTV. It's weird that mine seems to report the correct SWR for the band I select (as compared to my external SWR meter) but it shows it as being the same for all frequencies.? Maybe there is something
in my band configuration settings that is not right.
Tony
AD0VC
Just ran a SWR sweep on a QMX+ running 1_01_003 into a Cobweb and got this:
It seems to be reporting about correctly, The Cobweb is designed for 20, 17, 21, 24 and 28m.
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Chris, G5CTH
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On Thu, Apr 3, 2025 at 09:59 AM, mux_folder2001 wrote:
but I kinda don't want to go back one firmware level and lose my calibration.
You won't lose your calibration settings if you re-install v_027 of the firmware, unless you do a Factory Reset.
Firmware update preserves all compatible configuration settings across update versions.
Just this week I downgraded one of my QMX to 027, then went back up to 01_003, and the calibration was all still there.
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And I'm not seeing any improper behavior of SWR sweeps in 01_003 either.? They show my antenna behavior as expected.
Check to make sure you're really getting output power - SWR sweep will be wrong if the power isn't getting out (or back through T507).
Stan KC7XE
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On Thu, Apr 3, 2025 at 02:00 PM, mux_folder2001 wrote:
It is clearly not actually sweeping for some reason.
How can you tell?? You need to be monitoring the frequency to see if it is sweeping.
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Chris, G5CTH
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I can tell it is not sweeping when doing an SWR sweep because the external SWR meter holds steady while connected to my 6BTV. If I do an LPF sweep, the external meter swings all over the place as it sweeps.
Tony
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On Thu, Apr 3, 2025 at 02:00 PM, mux_folder2001 wrote:
It is clearly not actually sweeping for some reason.
How can you tell?? You need to be monitoring the frequency to see if it is sweeping.
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Chris, G5CTH
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Okay, I am running? and have run the calibrations, but haven't started adjusting band settings or attempting any SSB yet.? ?This is a QMX+ connected to a mag loop antenna.
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Keying CW on 40m, I got SWR protected, so I Menued into Hardware Tests > Tune SWR and and tuned.? The SWR reported is flickering around 1.7 and 1.8, which shouldn't trigger SWR protect.? ?Ah, but I'm connected to a mag loop antenna, and the SWR reported continues to flicker around 1.7 and 1.8 as I tune the loop all the way to 10m and back again.? The loop tuning is working, in receive I can hear the loop resonance moving as a peak in received noise.
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So I connect the serial monitor, go to the diagnostics page, and T on 40m.? It reports an SWR of 1.2-1.3.??
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Then I go back to the QMX menu to Tune SWR, and now it reports 10.? But I'm no longer sure what frequency the radio and the antenna are tuned to at this point.
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Then I turn the radio off for an hour.
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And when I come back I open the Serial Monitor, navigate to Hardware tests > SWR scan.? It scans from 3MHz to 9MHz and reports 10 for every frequency.? (But I realize later that I might have overlooked a dip at the resonant frequency, they can be easy to miss.)? I go back to the radio and tune the mag loop for maximum received noise.? I do another SWR scan it now reports 1.95 to 2.1 for every frequency in the scan.??
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I go back to Hardware Tests > Tune SWR and it now flickers around 1.9-2.0, but the SWR now responds when I tune the mag loop, and I'm able to tune it down to 1.33.? But I get SWR protected again before I can send my whole callsign.
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I begin to feel like an unreliable witness at this point.? I go back to Hardware tests > SWR scan.? It draws 10 except for a small spike down around 7.? I peak the antenna to 7025kHz and scan again, now I get an obvious and substantial spike down to 1.5 SWR.
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I'm sure there's a reasonable explanation for all this.
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-- 73 -- rec -- ad5dz --
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I tried switching back to 1.027 but it still would not sweep during an SWR sweep but then I noticed that the rig was set on VFO B! I switched back to VFO A and it sweeps correctly now!
That seems like a bug to me because the sweeps for everything else work with VFO B, just not the SWR sweep.
Whew.?
Tony
AD0VC
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I can tell it is not sweeping when doing an SWR sweep because the external SWR meter holds steady while connected to my 6BTV. If I do an LPF sweep, the external meter swings all over the place as it sweeps.
Tony
On Thu, Apr 3, 2025 at 02:00 PM, mux_folder2001 wrote:
It is clearly not actually sweeping for some reason.
How can you tell?? You need to be monitoring the frequency to see if it is sweeping.
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Chris, G5CTH
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On Fri, Apr 4, 2025 at 07:31 AM, Roger E Critchlow Jr wrote:
I'm sure there's a reasonable explanation for all this
Roger,
This behavior could result from a cold solder joint in T507 or its associated circuitry.? Temperature can change its connectivity.
Stan
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On Fri, Apr 4, 2025 at 04:49 PM, mux_folder2001 wrote:
but it still would not sweep during an SWR sweep but then I noticed that the rig was set on VFO B
The same here.
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73 Ludwig
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Stan --
And it shows up when I am making my first attempts to transmit.
-- rec --
On Fri, Apr 4, 2025 at 07:31 AM, Roger E Critchlow Jr wrote:
I'm sure there's a reasonable explanation for all this
Roger,
This behavior could result from a cold solder joint in T507 or its associated circuitry.? Temperature can change its connectivity.
Stan
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