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Re: USB audio levels

 

Looks like one of those fickle Windows mysteries, all back to normal now.
de VK6XT?
QMX+ VOX

 

I waited for and yesterday installed the 1_02_000 firmware.? I did a bit of tinkering
with the EQ to get some more emphasis in the mid-range (and worth noting that
when I do live sound at folk dance events, I always cut back the bass and emphasize,
not too much, mids and highs to improve intelligibility of the dance leader, just as Hans suggests).
?
And I made 4 SSB contacts on 20 meters with some Italian stations in a contest setting ....
running about 75 watts with the QMX+ and my HR-50+ amplifier.? Worked great.
Thank you, Hans ... you are a wizard!
?
One glitch ... I cannot get VOX to work.? I'm using one of Erik Larsen's microphones, which
clearly works fine in PTT mode and sounds OK.? I set microphone gain using the built-in
Mic Test ... goes red on just the loudest peaks.? On USB, speaking into the microphone
apparently triggers the VOX,? but it then cycles on and off until I manage to get QMX+ mode
out of USB over to LSB.? LSB doesn't work at all ... speaking into the microphone does not
trigger VOX.
?
Input device is set to "External Microphone".? And I'm using TRS (stereo) 1/8" mini cable
between the microphone and the QMX+.
?
Any hints will be much appreciated!
?
Thanks -
?
Bruce K1FFX
?
?
Re: QMX Internal Mic simulation

 

No,? thank you.? I agree it will work, so it is up to Hans now ?
I like to think I am smarter than this but...

 

I fired up my QCX 20M for the first time in over a year.? I didn't tune the antenna.? I sent a few dits and dahs, then when I checked I was at 2:1.? I am not transmitting into a darn near 1:1 and only seeing about 1.3 watts.? I know the QDX is very sensitive to SWR.? is the QCX also, did I likely blow my finals?? or is there a alignment that may need to be done since it has been so long since it was powered up?
?
Bob
Re: #qmx #Firmware release 1_02_000 #qmx #firmware

 

1_002 working well here. First DX QSOs last night - Auckland NZ to Portland OR and Italy!
Re: #qmx #Firmware release 1_02_000 #qmx #firmware

 

Upgraded to the latest 1_02_000 firmware from the 1_01_003 beta with no issues yesterday.? Calibration ran fine.?
?
Today had the first QMX+ to QMX+ message exchange using the FreeDATA protocol, between Ohio and Maine on 20m.
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What a great little radio!
?
-Dj
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Re: QMX Internal Mic simulation

 

Thanks George for testing the internal mic yourself. The audio quality might not be the best in this way, but could be enough for making quick and short QSOs.
?
73,
Yoon KM6KJI
Re: QMX+ Low Power After SSB Update

 

I bit the bullet and went back to the previous firmware version: xxx.027, without the SSB support. Sad to report that the RF output power has not changed - still about half of what it was before running that *&*^^%$ calibration procedure. I certainly won't be doing that ever again. :-(
?
Hans - any idea what has happened and how to resolve it?
?
I've got a handful of spare BS170 FETs in my parts box. Is it possible that the calibration thing clobbered one or two of the installed ones? What can I measure to check?
--
Jim / K7TXA
Eagle, ID

SKCC 10447T
BUG 301
Re: QMX+, strong noise in receiving

 

Jean-Jacques,
?
so you received something. But I don't know about the signal strength and the noise. Hard to say something more.
?
Some question:
  1. Did you receive the same signal via an other RX? If yes, what was the SNR?
  2. For the 30 m recording did you transfer the audio via USB to the PC or via QMX audio out and PC audio in (direct, not via microphone)?
  3. Why did you record only one canal?
  4. Could you record two canals audio via USB, QMX connected to the dummy? And after this the same recording using an antenna and receiving a signal? (recordings by Audacity)
  5. Do you have a signal generator (plus attenuator) to produce low signals, let's say 4 ?V and 1 ?V. If yes could you record audio from a low signal like in No. 4?
  6. Could you record all using a band with high noise and a band with the lowest noise?
Please switch off the AGC for all recordings and use CW mode with the same bandwidth.
?
73 Ludwig
Re: Heavy ssb tx distortion

 

Hi Ricky,
?
I had similar issues with some of the electrets I tried. I settled for using my pc headset with built in mic with and a mic preamp module MAX9814.
?
Mel. M0KMD.
Re: #qmx #Firmware release 1_02_000 #qmx #firmware

 

After upgrading the firmware and building K6ARK's elecrtet mic, I had multiple successful SSB QSO's on 20/40m with both my high and low band QMX's.
Thanks to Hans and all the beta testers.
?
Brad, AB4BA
Re: #qmx #Firmware release 1_02_000 #qmx #firmware

 

Wow Hans,?
Congrats, awesome, fantastic...?
?
Will the internal microphone work with the official firmware or is this a subject to be done in another Firmware update!?
?
73 de Matt, DL1SER
Re: #QMX #Volatage #Transmit #Volatage #Transmit #qmx

 

¿ªÔÆÌåÓý

It is Q507.?

Tony
AD0VC

From: [email protected] <[email protected]> on behalf of Marek SP9TKW via groups.io <sp9tkw@...>
Sent: Sunday, May 4, 2025 2:35 PM
To: [email protected] <[email protected]>
Subject: Re: [QRPLabs] #QMX #Volatage #Transmit
?
thanks Tony, could you tell me what number on schematic is this transistor? I will check for shorts etc...
?
---------------------------------
73 de Marek SP9TKW
Re: QMX Internal Mic simulation

 

Hi Yoon
The quality ain't too bad, actually ok but,
there is a squealing low level noise in the background. Thanks for the info because I could use that in an emergency. Very convenient so I would like the Mic kept in any future board revision!?
Best 72,
George?
QMX gets a full POTA trial

 

¿ªÔÆÌåÓý

Park US-3843 today, central NC. Low humidity after yesterday's storms. ?Slight breeze.?

QMX built for 9w
Dork regulator DROK Adjustable Voltage Regulator...
Bioenno 9v battery
SOTA Beams Bandhopper
Palm pico paddle

Why I love this rig: even though it is menu-driven, it seems SO INTUITIVE that it doesn't seem difficult to do what I want. ?Hans must have done some serious human factors analysis with the rig.?

Also, the receiver is outstanding.?

I made 24 QSO in 45 minutes on 20. The beacon CW message capability is superb. ?

Thanks to all for the Drok regulator suggestion.?

And thanks to Hans!!

Mark Lunday
wd4elg@...
Re: #QMX #Volatage #Transmit #Volatage #Transmit #qmx

 

thanks Tony, could you tell me what number on schematic is this transistor? I will check for shorts etc...
?
---------------------------------
73 de Marek SP9TKW
Re: Heavy ssb tx distortion

 

On Sun, May 4, 2025 at 08:17 PM, Ricky wrote:
The one everyone is using is -25db could this be the issue.???
Ricky, I guess yes. Using the default settings only some peaks of your voice are coming through. If you would set Microphone gain much higher you would add a lot of noise.
?
You may read this SSB settings.
?
73 Ludwig
Re: #QMX #Volatage #Transmit #Volatage #Transmit #qmx

 

¿ªÔÆÌåÓý

In diagnostic mode the transmitter voltage should be very low, like .4 volts until you press T. It is red in the first image because it is way too high. The modulator transistor is either shorted or being forced on by some circuit fault.

Tony
AD0VC

From: [email protected] <[email protected]> on behalf of Marek SP9TKW via groups.io <sp9tkw@...>
Sent: Sunday, May 4, 2025 2:09 PM
To: [email protected] <[email protected]>
Subject: [QRPLabs] #QMX #Volatage #Transmit
?
I have QRP-Labs build QMX mid-band Rev.4 f/w v_027 which is blowing finals. So far two sets, third set in.
?
Transmitter Voltage is showing in RED to start with.
?
Here are diagnostics screens
?
?
After pressing "P", screen changes to this
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And after pressing "T" screen changes to this
?
?
Off course all into dummy load.
?
Calling few CQs into dummy load, I can see that finals get very warm and familiar smell is being emitted.
?
As I said two sets of BS170 have been already smoked. Any pointers what to check.
Display SWR reading seem correct as well as output power.
?
Please help.
---------------------------------
73 de Marek SP9TKW
#QMX #Volatage #Transmit #Volatage #Transmit #qmx

 

I have QRP-Labs build QMX mid-band Rev.4 f/w v_027 which is blowing finals. So far two sets, third set in.
?
Transmitter Voltage is showing in RED to start with.
?
Here are diagnostics screens
?
?
After pressing "P", screen changes to this
?
And after pressing "T" screen changes to this
?
?
Off course all into dummy load.
?
Calling few CQs into dummy load, I can see that finals get very warm and familiar smell is being emitted.
?
As I said two sets of BS170 have been already smoked. Any pointers what to check.
Display SWR reading seem correct as well as output power.
?
Please help.
---------------------------------
73 de Marek SP9TKW
Re: #qmx #Firmware release 1_02_000 #qmx #firmware

 

On Sun, May 4, 2025 at 02:20 PM, Martin+HB9GVW wrote:
An idea: what would be an addition is an audible SWR indication in case the tuner is a few meters away from the QMX, eg progressively longer dashes if the antenna is too long, short dits if the antenna is too short. In the range of say SWR <1.5 a continuous tone is heard.
I didn't think this through. Just sitting on a frequency with a given tuner setting gives you an SWR, but doesn't tell you on which side of the optimum you are. Only by changing the tuning knobs you can know whether it's getting better or worse.
There should be an indication as well to the actual SWR and as to improvement / deterioration when you change the tuning.
?
73 de Martin / HB9GVW
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