Re: QMX: Requiescat in Pacem
Even if it is not yet Easter my QMX stood up from the deaths yesterday: Based on Hans' feedback to my dead QMX as was pretty sure, that the CPU would have been killed due to a voltage difference between
- the USB connection to my laptop (running on one potentially ungrounded power supply)?
- the 12V supply power comming from an ungrounded lab power supply
Yesterday I disassembled my QMX from the enclosure and pulled out both power supply (SMPS) PCBs. I then added jumper wires for GROUND and VDD (3.3V) to the main board PCB#2 connector and supplied 3.3V (JP104 Pin 4 and Pin 2 GND) from a current limited lab power supply and slowly increased the voltage while watching the current. At 3.3V I saw a current consumption of approx. 150mA --> Hooray, CPU not shorted, most probably OK! I then checked the PWM_3V3 and PWM_5V signals on the main board, that are directly coming from the CPU --> 116.4kHz rectangle signals --> CPU is working. As a next step I put in the SMPS PCB#1, to create the 5V and pass through the 12V, that I connected through the power supply connector with 3.3V still being supplied directly to the main board. Again I had high current consumption on 12V --> problem must be on SMPS PCB#1! I pulled out SMPS PCB#1 and put in SMPS PCB#2 for 3V3 supply. I fed 12V to the main board 12V connector of PCB#1 (JP101 pin 4) and saw 3.3V coming out of SMPS PCB#2 and a nice 116.4kHz signal on PWM_3V3: I was now suspecting, that the 5.6V Z-diode D108 on SMPS PCB#1 had a short, desoldered it and soldered in a new one. Unfortunately a 3W 5.6V Z-Diode, that I had ordered, was too big to fit into this place, so that I had to put in a glass 5.6V Z-diode. Put in PCB#1, connected 12V to the power connector of the PCB, slowly raised to voltage and again hooray, QMX was working again!! I updated to the firmware from 1_00_012 to 1_00_017 without any problems and the QMX seems to be working fine. That D108 obviously took up its protection role and died with a short is for me a strong indication, that the SW based switching regulator still has problems...
I think my use case to provide power to the QMX from one power supply and have a laptop conencted with a different power supply with at least one ungrounded is not an common scenario, if you run FT8. -- Vy 73, DB2OO -Joerg
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Re: WSPR Receive Frequency on QCX Mini With TCXO
On 17/02/2024 08:13, dl3naa via groups.io wrote: Karl, there is another possibility Which reminds me, it is possible to bypass the QCX filter with a switch. Makes SSB receive possible but not good. WSPR does its own filtering. 73 Alan G4ZFQ
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Re: QDX High bands question
Hello William
The T37-17 (yellow/blue colour) toroids replaced the shiny black ones in the QDX high bands kit in March 2023. The current assembly manual does reflect this fact. Please could you check that you have the latest manual revision?
73 Hans G0UPL
On Sat, Feb 17, 2024, 11:58?AM k6whp < k6whp@...> wrote: On Wed, Oct 11, 2023 at 07:07 AM, Hans Summers wrote:
So the manual is correct... according to experience - experience being slightly different from simulation expectations - and if you build according to the manual you probably stand the best chance of getting a good output power.?
Hans,
Forgive the resurrection of this thread, but, in beginning to sift through the parts of my QDX kit, I noted the cores designated for L2, L3, L4, L6, L8, and L10 were described as "37-10 toroid (shiny black)", yet those supplied to me were a garish blue and yellow color. I am a UCLA graduate and these are my alma mater's colors and that's fine. I am nonetheless leery of these not being "shiny black".
Is my kit-building experience over as I know it or is there hope for me yet?
** sobs mournfully**
TIA.
--
William, k6whp
--------------------
"Cheer up, things could get worse. So I cheered up and things got worse."
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Re: WSPR Receive Frequency on QCX Mini With TCXO
Hi Peter,?
Thanks very much for the modification information.? I'll watch and read up and if I feel it's doable with my modest abilities,? I'll probably have a crack at it. I've had several WSPR stations pop up this morning on 14.0964, so thanks again also for letting me know regarding the filter width.? I have used the radio on WSPR for transmitting,? but didn't think about the filter implications for reception. Then when I did, became mightily confused!
Karl?
DL6DAV?
Sent from
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Re: QDX High bands question
On Wed, Oct 11, 2023 at 07:07 AM, Hans Summers wrote:
So the manual is correct... according to experience - experience being slightly different from simulation expectations - and if you build according to the manual you probably stand the best chance of getting a good output power.?
Hans, Forgive the resurrection of this thread, but, in beginning to sift through the parts of my QDX kit, I noted the cores designated for L2, L3, L4, L6, L8, and L10 were described as "37-10 toroid (shiny black)", yet those supplied to me were a garish blue and yellow color. I am a UCLA graduate and these are my alma mater's colors and that's fine. I am nonetheless leery of these not being "shiny black". Is my kit-building experience over as I know it or is there hope for me yet?** sobs mournfully** TIA. -- William, k6whp -------------------- "Cheer up, things could get worse. So I cheered up and things got worse."
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Re: WSPR Receive Frequency on QCX Mini With TCXO
Karl, there is another possibility but I never tried it myself as I am a huge CW-fan and dont want to loose the filter:
With this Modifikation you should be able to use a QCX for transmitting AND receiving WSPR.
Good luck!
Peter DL3NAA
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
I've listened to this weekend contest in 20 and 40m bands and tinkered with AGC settings some more. I've also tried Paul (W9AC) suggestion to increase "Smooth samples", and it seems to alleviate the clicks on TX.
My goal was to keep reasonable good dynamics and make RX as less tiresome as possible. Here's what worked for me:
It's nice to have so many options =) =)
Regards,
YO3GFH
op. Adrian
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Re: #QMX #Japanese Band limits does not work Ver. 1_00_12
#qmx
#Japanese
Hans;
Now I understand that the reason 5MHz band is still on the menu is to enable rx only, but no tx is allowed.? Many thanks!!
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
Hi Roy
> Something to do with reducing > the value of Sample blocks > appears to make QMX grumpy.
Thanks... I'll fix that. No problem. It's just that pesky AGC sample buffer again... It's in use all the time audio is running. When you go in and change the size while it's in use things can get confused. You'll find probably it crashes sometimes not others, when you change sample size. I can fix it easily don't worry. For now, restarting QMX will recover it.
73 Hans G0UPL
Hans, FYI:
I just tried to set Paul's "good start" settings (post below), not through Terminal, but through the QMX menu. After finishing, selecting the right push-button to step out, my QMX locked-up with just "Audio" showing. No buttons worked including power off, so had to power off by pulling the plug.
On re-start (plugging back into power and starting), QMX came up just normally, and all settings I made were still present.
I was able to reproduce the issue (again, Menu settings via QMX, not terminal) by trying a few things. This is what did it in:
- moving "Sample blocks" back up to 5 (your originally published settings to try)
- backing all the way out of menu. (QMX working OK here)
- returning to Menu -> Audio -> AGC Settings -> Sample blocks
- reducing the Sample blocks to "2".
- back -> back (to AGC Settings) -> back (to Audio)
- QMX totally hung now
Something to do with reducing the value of Sample blocks appears to make QMX grumpy.
Roy - KI0ER
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
Very pleased with the new features.? The QMX is growing up now. Well done Hans! One thing for my wish list would be a variabel filter setting for CW. I'm working a lot of guys using homebrewed tx or ww-2 gear. They are not spot on most of the time and VFO' s tend to drift. This morning I had a QSO? with a om who returned to my cq about 150 Hz lf and I first did'nt hear him. Now I'm using RIT and tune around my calling frequency after a cq.
73 Durk PA3BYW?
Hans,
Thanks so much for this, a great improvement on CW!? Paul, thanks for thes ettungs, I've been playing around with them a bit with QSOs on 30M and litening to the 'test on 40M.? Think I'll end up somewheer between youe settings and Hans LOL.? Owning an Elecraft K3 and K4 means I've done a lot of playing around with AGC settings!
73, Bill NZ0T
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Re: WSPR Receive Frequency on QCX Mini With TCXO
Hi Bruce,?
I'm getting nothing on 14.0971. However,? as per Peter's suggestion,? 14.0964 provided a few hits late yesterday evening.? Hopefully, there'll be more today when the band wakes up.?
Karl?
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Re: WSPR Receive Frequency on QCX Mini With TCXO
Thanks, Peter?
This generated a small number of hits late last night.? I will try again later this morning when the 20M band is more lively.?
Karl?
Sent from
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March QST has two articles praising the QCX & QMX for portable ops!?
--
73, Dan? NM3A
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
Hans,
Thanks so much for this, a great improvement on CW!? Paul, thanks for thes ettungs, I've been playing around with them a bit with QSOs on 30M and litening to the 'test on 40M.? Think I'll end up somewheer between youe settings and Hans LOL.? Owning an Elecraft K3 and K4 means I've done a lot of playing around with AGC settings!
73, Bill NZ0T
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
The DX contest is proving to be a great way to test the AGC.
And it is working quite nicely.? Thanks, Hans!
Just hopped on 20m and snagged two Spanish stations and a Hawaiian station.
Amazing what 4W and a 15ft dipole can do when the band is open.
73, Mike KK7ER
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
Hans, FYI: I just tried to set Paul's "good start" settings (post below), not through Terminal, but through the QMX menu. After finishing, selecting the right push-button to step out, my QMX locked-up with just "Audio" showing. No buttons worked including power off, so had to power off by pulling the plug. On re-start (plugging back into power and starting), QMX came up just normally, and all settings I made were still present. I was able to reproduce the issue (again, Menu settings via QMX, not terminal) by trying a few things. This is what did it in:
- moving "Sample blocks" back up to 5 (your originally published settings to try)
- backing all the way out of menu. (QMX working OK here)
- returning to Menu -> Audio -> AGC Settings -> Sample blocks
- reducing the Sample blocks to "2".
- back -> back (to AGC Settings) -> back (to Audio)
- QMX totally hung now
Something to do with reducing the value of Sample blocks appears to make QMX grumpy. Roy - KI0ER
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
On Fri, Feb 16, 2024 at 02:04 PM, <nz0tham@...> wrote:
I got 17 loaded just fine.? Anyone have suggested AGC settings to start with?
73, Bill NZ0T
See below.? The high "Smooth Samples" setting seems to eliminate much of the audio clicks.? The remaining settings give reasonably good dynamic range while limiting strong signals. I'm still experimenting with values but this is a good start. Paul, W9AC ?
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Re: An interesting diagnosis
All I can say it’s a good thing I had lifted the leg of pin 32 of the cpu that was NG before I removed it. ?That saved me. ?
Jeff
W1NC
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Re: #qmx #firmware 1_00_017 AGC, S-meter, LPF sweep
#qmx
#firmware
I loaded .17 and it is working well on digi with iFTx on the iphone. ?Thanks to Hans ill be trying it out on the next SOTA outing.?
On Friday, February 16, 2024, 3:30 PM, Hans Summers <hans.summers@...> wrote: P.P.S. yeah there's a lot of clutter in there. Like my workbench (see attached)... the QMX "Lab" is almost as cluttered as the real one.? On Sat, Feb 17, 2024 at 1:27?AM Hans Summers via <hans.summers= [email protected]> wrote: P.S. Attached... "The Lab" Easter egg...?
On Sat, Feb 17, 2024 at 1:25?AM Hans Summers via <hans.summers= [email protected]> wrote: I got 17 loaded just fine.? Anyone have suggested AGC settings to start with?
Adrain?YO3GFH said:
"I configured AGC with the values seen in your screen captures, they seem pretty sane, I only changed "Recovery dB/s" (from 10 to 15) and "Threshold S" (from 8 to 7)."?
I think that is reasonable...?
I remind all that: - I was being a little extreme perhaps in my settings, because I wanted to see what goes on, during my development and testing
- I had long hang time and slow recovery dB/second because again, I wanted to see what was going on, and be able to demonstrate in the video?
- My video test case was also extreme... S9+30dB... to demonstrate the extreme capability of the AGC system to totally delete any possibility of that massive signal reaching the earphones, in this case it instantly applied about 36dB attenuation, and no blip at all is seen on the Audacity software's recording of the audio (which is also streamed over the USB sound card interface concurrently to the audio output). And also to clearly show everything for the video.?
- My 40m noise floor is too high here right now, as I said on the video, my antenna fell down. It doesn't work as well lying on the roof which has a metal frame inside the tiles.?
Easter egg: If you press the D key on the terminal screen, in the main menu, you get my secret "lab", it's my playground which I use during development of my various functional additions, and for debugging, etc. What's in there now is some debug info on the AGC as that's the task I had most recently on the lab bench. Might be interesting, if you are wanting to play with the AGC.?
--
Jginaz
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Re: WSPR Receive Frequency on QCX Mini With TCXO
Tune the dial ?to the centre of the WSPR band 097100
Tones will vary between ?600 and 800 but you should have a full passband to pass to the PC
Any Hum etc on the audio connection ?ruins the chances of decoding anything but you should still see a few carriers in a waterfall?
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k6whp
Paul Christensen
Bruce Akhurst