Re: QMX(+) Build experience, Poor Audio Filter Sweep/RF Filter Sweep/Image Sweep/ADC IQ test and resolution with new PCM1804
I think L403 is coming off the board tomorrow....
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73
Karl
KI4ZUQ
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Re: QMX and power bank PD
I seem to have found my way into the Monty Python 'room for an argument'
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Re: QMX and power bank PD
Muhsin is correct.? As I noted in my original reply, some 2.5mm connectors may work.? Some are designed with spring contacts, and are advertised as being compatible with 2.1mm.? And those do achieve a good contact.?
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However, Muhsin, if there are two choices in a connector for a QMX trigger cable, and one of them is 5.5/2.1mm, as is the case with buying most brands of trigger cables, the correct and best choice is ALWAYS the 5.5/2.1mm connector.? It will provide better performance over the long term, and will avoid confusion with 2.5mm connectors which don't have spring connectors, and are dangerous for use with QMX/QMX+.
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Stan KC7XE?
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Re: QMX+ no power output, low SMPS bias current
On Sun, Apr 6, 2025 at 06:43 PM, <mitchellrlawrence@...> wrote:
I am going to start form the bnc and work my way back through the circuit unless I find any other advise?
Be aware that the VSWR transformer winding puts a DC (not RF) short across the output BNC connector.
73, Don N2VGU
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Thanks Stan and John. I think that's what I probably did; changed the mode from WSPR to CW by mistake during transmission. I'll try again once I am out in another park soon.?
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Re: QMX and power bank PD
On Sun, Apr 6, 2025 at 11:48 PM, John Pokluda wrote:
oversized barrel
It is not a barrel, it is spring based, works with 2.1mm 73 DE muhsin TA1MHS
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First check keyer menu and check your not in practice mode and then display and in CW mode.
This mistake I have made many times!
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Re: QMX and power bank PD
On Sun, Apr 6, 2025 at 11:48 PM, John Pokluda wrote:
Why on earth take the risk with an oversized barrel, even after Hans' otherwise comment?!
Hans's comment is: 5.5 x 2.1 is correct.?
my comment is: THIS?5.5 x 2.5mm?plug?
on?
works?with?no problem!
Both are true you can change the plug if you want. 73 DE muhsin TA1MHS
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Re: QMX+ no power output, low SMPS bias current
Hard to understand measuring SWR if you truely have 0 watts out... :-)
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Paul -- AI7JR
On Apr 6, 2025, 15:43 -0700, mitchellrlawrence via groups.io <mitchellrlawrence@...>, wrote:
I just finished my build sounds similar to your issue?
0 watts
9.xx volts?
swr jumping a little mostly around 1.2-1.5
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I am going to start form the bnc and work my way back through the circuit unless I find any other advise?
let me know if you discover anything!!
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Re: QMX and power bank PD
Why on earth take the risk with an oversized barrel, even after Hans' otherwise comment?!
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Re: QMX+ no power output, low SMPS bias current
I just finished my build sounds similar to your issue?
0 watts
9.xx volts?
swr jumping a little mostly around 1.2-1.5
?
I am going to start form the bnc and work my way back through the circuit unless I find any other advise?
let me know if you discover anything!!
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Re: QMX and power bank PD
On Sun, Apr 6, 2025 at 05:11 PM, Stan Dye wrote:
Some 5.5x2.5 plugs may work.
But you inherit extra risk of intermittent power connection, which for some users has resulted in damage to their QMX internal power supply.?
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Stan
THIS 5.5 x 2.5mm?plug?
on
works with no problem!
other people are using it with their PDs and QMXs on POTA activities.
I tried to get an ?intermittent contact just for you, but I couldn't, sry.
73 DE muhsin TA1MHS
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Re: Available Hand Mics for QMX SSB ?
All the mics I have assembled and tested with my QMX+ (which is now a LOT of mics) have had various results. I have not changed the default settings from the SSB firmware, but some elements pick me up from several inches away and others I need to be about about 3 inches from the mic. This is not a problem for me, I like to hold the mic close anyway, so I usually have to turn down the mic gain. Every mic element will be slightly different.
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All the elements that I have used and tested were adequate to pick up my voice with the default settings in my QMX+ and hear it well with my Yaesu FT-710. (QMX transmitting into dummy load, FT-710 has 18dB attenuation turned on and an G5RV antenna in the back yard) I have not found one yet that I thought was inadequate for the job. I did notice a slight difference when I used a "cheap" (not inexpensive cheap, but flimsy cheap) and a nice cable. The better quality cable yielded slightly better performance.
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Re: Broken L512 toroid.... T37-10 (Black)
Thanks Ronald....they look promising...:)
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#qmx #SSB Firmware beta 1_01_000 release
#ssb
#qmx
Hi all,
This is my experience?with the SSB beta release.
After much fear and?consternation, I took the plunge today and installed the SSB beta firmware in a QMX Rev 1. I attempted to do a calibration on Putty, but the R and O commands would not work. This could be due to my inexperience with Putty or a failure to understand the?instructions. I disconnected the?QMX from my laptop and was able to run the calibration from the Hardware Tests screen on the radio. The QMX got a little warm, but the?calibration was apparently successful. Afterward, I checked the CW power output on?several bands, and it appeared to be normal (same output?I had before the calibration). I did not put the QMX back on Putty to check the calibration curves.
I tested the?SSB mode with a QRPguys microphone?kit and made 8 successful?phone contacts on 20M. Audio and signal strength reports were good. The?mic is covered by a cutdown foam windscreen purchased from Amazon, and the only mic setting I adjusted?was compression set at 5. I found the best output occurred while talking straight down into the mic held about an inch from my mouth. Probably because the mic element is a setback from the vinyl cap. I have not tried other?bands yet.?
I am mainly a CW op, but after the successful SSB implementation I may have to start making more phone contacts. I'm almost embarrassed to say it was fun!?
72, Randy NR5N
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So far everything seems to be functioning well. I have noticed that when using the swr tune function that on some bands the swr reading does not change while tuning an antenna and I have to turn it off then on again to get a new reading. This didn't happen before and would change as I operated a tuner.
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Randy
VE3JO
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Re: Available Hand Mics for QMX SSB ?
Thanks Stan. I think I will also order the same mic Hans used. Comparing the sensitivity specs between that mic and mine shows quite a difference in sensitivity. I am also going to try a higher quality 3.5mm cable.
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73, Jared, N7MAW?
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Re: Broken L512 toroid.... T37-10 (Black)
Here's one source Bill
Ron
I've broken one of the T37-10 (Black) L512 toroids.? Do you know where I might get a replacement?
Thanks,
Bill
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Re: Swr meter in SSB mode
That's the same for me, everything is fine in CW and Digi but SSB is weird
On Sun, Apr 6, 2025, 5:20?PM Barry Palmatier via <BarryPalmatier= [email protected]> wrote: I have the same problem on my qmx. It only happens in SSB mode. In CW everything is normal.
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Karl
Donald S Brant Jr
Grant
Paul - AI7JR
Ronald Taylor