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QMX and FT8CN audio issue - strange issue

 

You might actually need an OTG cable off the tablet. My limited experience with interfacing radios to tablets have always needed an OTG cable.
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73 de VE4ACE
 

On Mon, Nov 18, 2024 at 09:18 PM, Jim VE4BWG wrote:
I am still scratching my head over how to get the QMX to transmit from the FT8CN app
I use FT8cn with my Samsung S20+ phone all the time with no issues.? It works great
I don't have to use the dongle approach, but that may be required by some devices to get their USB-C to switch to the OTG mode.
In the FT8cn settings I chose:? Control=CAT, Connection Type=USB, Rig=QRP Labs QDX
Then on the 'Calling' screen, I touch the icon in the upper-right corner to enable the transmit, and it just works.
Touching CQ will start my CQ on the next timing boundary.?
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When trying to transmit, does your QMX turn on the little dot under the A to show that PTT was enabled? Does the other dot turn on to say it is receiving audio?? Of course if the dots turn into a line, then all is working...
One note: if I have all of the same settings, but don't plug in the cable to the QMX, the audio from the CQ comes out on the phone's speaker.?? That helps me know that I am operating the program correctly.
Stan KC7XE
 

I had the same problems with my QMX:
no TX:
Windows 10 desktop with JTDX: TX FT8 no problem
Tablet XIAOMI Pad5 (Android13, XIAOMI HyperOS) FT8CN: TX very briefly, then 2 points, nil? ->Threshold GMX at 60:? ->TX FT8 no problem
Smartphone Poco (Android 14, XIAOMI HyperOS): TX very briefly, then 2 points, nil? ->Threshold GMX at 45 (!):? -> TX FT8 no problem
The Android devices obviously produce lower levels.
bad SWR - "S":
Tune produces good SWR, TX breaks off with "S" in the display? -> Cause: Very short interruptions in the cable connection due to poor contact of the ground of the BNC plugs. Plugs wobble a bit, but OHM meter usually shows OK. Tune with QMX works without errors with good SWR, the short interruptions are ignored by the SWR protection in Tune-mode. If something moves during transmission (QMX, cable), the interruptions occur and the QMX switches off. The dummy usually works because other cables are used. Remedy: Carefully bend the inner ground contacts in the plug a little (very fragile, about 1/10mm, not more).
It could also be another loose connection.
 

Stan, still no joy getting the Android Galaxy A7 Lite tablet (with USB-C port) to put the QMX into Xmit mode with FT8CN.
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Notes:
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- in the top right corner of the 'Calling' page there is a very small green dot
- in the top right corner of the 'Decode' window I have the flashing red mic icon - pressing it did nothing
- 1 dash appears under the 'A' during receive periods
- 2 dashes appear under the 'A' during the period that the FT8CN app shows in Xmit mode, but the QMX does not transmit
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For these tests I used (1) USB-C male to USB-A female dongle and a USB-A male to USB-C male cable. I had also tried an ordinary USB-C male to USB-C male cable by itself. Neither enabled Xmit.
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QMX settings: (1) VOX off - USB - QDX (2) VOX off - USB - TS-480. (2) VOX on in both devices. No Xmit
--
Jim
VE4BWG
 

Jim, with the 'one dot' and the 'two dots' appearing as you describe, it means the Android is properly keying your rig, and sees it's sound device and is sending sound data to it.? But the output sound is of too low a level to trigger the transmit.? So if your Android has no further controls to increase the output level, you can go into the QMX "Digi interface" menu, and try decreasing the "Rise Threshold" parameter to a point that it will detect the signal.? When you find one that works, you will also need to decrease the "Fall Threshold" to a value lower than your "Rise Threshold".? It is safe to go all the way down to 0 if you need to - but you may get a cleaner output at the beginning and ending of transmissions if you can use higher values.? See if that works....
Stan KC7XE
 

Hello again Tom,
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Sorry for the delay.
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Here's some pics and links from Amazon for what I've been using:
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INIU Power Delivery (PD)Bank - A terrific performer. I use them for the Q's and to power my mini laptop in the field that requires 20V at 65Watts.
Not cheap, but known 'good stuff'. There is a Black Friday sale going on now.? I charge them with the 65W fast charger that came with the mini laptop.
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PD Adapter - 12V? - Work fine on my Q's that are still 'stock'?
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https://www.amazon.com/NFHK-5-5x2-1mm-Adapter-Emulator-Trigger/dp/B0B9RDJ1YK/ref=mp_s_a_1_1?crid=26BM0GAGSUFE2&dib=eyJ2IjoiMSJ9.E6HgZqeiPBeQ6K8IAV-7k0YCCo7WFj9mEFfiaG6pfVNCmg7LGX871CYRIP3JkhW18fJ0q1Z_abXVVA44DciOOzJqvHh7AuWuWPjXVTqPOUfYLZdciPl-nurtAcj697M5NqwOP2X7HssKXMMyY8Bv00TginoJRZaCKaqnunaKc9hn3DmWTR1NGqxPoP9t6Q04sOr9f1U4ISgwcLVPCEQ11A.pOcza_o7AkJAzP33TPU5mtAriCjN-rJlgSghjtBCMtk&dib_tag=se&keywords=12+volt+pd+trigger+adapters&qid=1732196383&sprefix=12+voly+pd+trigger+adapters%2Caps%2C133&sr=8-1#
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PD Trigger Kits (Do it yourself . . . :)? ?I got these to experiment and because I modified a couple of my Q's to use different DC power in jacks that have locking collars on the plugs and are 5.5 x 2.5 (vs the OEM 2.1). Bit fiddley to change Voltage resistors if you want volts other than the 12V that they come set for, but not too hard to do. Plenty of extra resistors in the package. Liked them so much I bought a second 5 pack to save for the future.??
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https://www.amazon.com/Voltage-Trigger-Module-Type-C-Default/dp/B0BGHZ8V3B/ref=sr_1_1?crid=TX29KGPZE1L4&dib=eyJ2IjoiMSJ9.YrTSINAd_reAG3EOZcUec5opTXJ0t_Lwxnw-Zm1DuPuYJu3xrCN_QOBROgZ59PxoyItsc_POpiN1ba_rLOE5mvQPDFLSdKzzZuDimr6mz7NjSmFi5RqxHvmWhhI_gVQ45WVDrZwHTBTZhPRfzE5LexjkvvA6LALZuYlJewG52HFBU_kUSsvzEyPbW_-W6PdzFqoFigd5GG_x57sGzS0aM-_QAhC04s7SjuJFpI2lfc4.LIa6u3dxxujBthVrApcYAqHQT3HluhnxqArYCJmheA8&dib_tag=se&keywords=5PCS%2BUSB-C%2BPD%2BQC%2B5V%2B9V%2B12V%2B15V%2B20V%2BDC%2BFixed%2BVoltage%2BPower%2BTrigger%2BModule%2B5A%2BType-C%2BMale%2BInput%2B(Default%2B12V)%2C%2BWhite&qid=1732197914&sprefix=5pcs%2Busb-c%2Bpd%2Bqc%2B5v%2B9v%2B12v%2B15v%2B20v%2Bdc%2Bfixed%2Bvoltage%2Bpower%2Btrigger%2Bmodule%2B5a%2Btype-c%2Bmale%2Binput%2Bdefault%2B12v%2B%2C%2Bwhite%2Caps%2C197&sr=8-1&th=1
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Hope this is helpful.
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73 GREG KI4NVX
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I had a similar problem with my Samsung tablet. In my case the solution was to turn up the tablet audio out volume to maximum. That got me on the air!
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73, Rick
VE7TK

Website:

 

I wanted to quickly share my experience with the INIU Power Delivery (PD)Bank (in my case, the smallest 10000mah variant), versus others like the Baseus 65w 20000mah PD bank I also have. ?The INIU gives me trouble on a few fronts:
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1) If the power draw is too low like when powering my noise canceling speaker, the INIU shuts off, whereas the Baseus is always ready to instantly deliver, even with nothing plugged in to a PD trigger cable.
2) My INIU model supports PD, but doesn't seem to support QC (as indicated) -- which is another way to get power out of the Baseus (for example).
3) I can't seem to have the PD trigger cable deliver low levels of power, and also get juice out of a USB-A port from the device concurrently.
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My experience may not be the same for all models in the line-up, but I'd have opted for another Baseus, had I known.
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Garrett
pp5/kc3unp
 

FWIW . .
I am using my 25000nah INIU power bank to concurrently run a small 5V cooling fan ( 30ma) from the USB A port at the same time as my QMX at 12V or my QDX at 9V via PD trigger adapters on the main USB C output port.?

I did notice a glitch a time or two where the power dropped to the Q's when I plugged in the fan AFTER having already plugged in the Q's. Fortunately, about the same time as I noticed that glitch, another OP posted that some PD banks will default all the ports to 5 V with same cable sequencing.?

I haven't tried to reproduce that as I just got in the habit of plugging in the 5V fan USB cable first. No glitches since.?

GREG KI4NVX?


On Thu, Nov 21, 2024 at 11:35 AM, Garrett kc3unp via groups.io
<kc3unp@...> wrote:
I wanted to quickly share my experience with the INIU Power Delivery (PD)Bank (in my case, the smallest 10000mah variant), versus others like the Baseus 65w 20000mah PD bank I also have. ?The INIU gives me trouble on a few fronts:
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1) If the power draw is too low like when powering my noise canceling speaker, the INIU shuts off, whereas the Baseus is always ready to instantly deliver, even with nothing plugged in to a PD trigger cable.
2) My INIU model supports PD, but doesn't seem to support QC (as indicated) -- which is another way to get power out of the Baseus (for example).
3) I can't seem to have the PD trigger cable deliver low levels of power, and also get juice out of a USB-A port from the device concurrently.
?
My experience may not be the same for all models in the line-up, but I'd have opted for another Baseus, had I known.
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Garrett
pp5/kc3unp
 

Hi Stan. Success. But in order to get FT8CN to trigger the QMX I had to lower the rise/fall values to zero. I will experiment more tomorrow with rise/fall values to delve into this a bit deeper. Of note: (1) USB-C male to USB-C male cable does not work; (2) Success came with a USB-C male to USB-A female dongle connected to a USB-A male to USB-C male cable; (3) Cat - USB - Kenwood TS-480 (QDX did not work).
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Although I was putting out about 5w I had no establishing contact with a calling station. As well my CQ calls only attracted one reply. I check PSK Reporter and I was getting out fairly well.
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It was a good afternoon. I even got iFTX running FT8 successfully on an iPhone XR / QMX combo. That was with a Lightning to USB-A female connected to a USB-A male to USB-C male cable. Successfully logged my first QSO in 40 years - KF9TS EN54. Not a long hop but it made me smile. PSK Reporter showed my QMX signal was heard all over Continental USA and in China and the Azores. Not too bad for a sloping 41' EFRW (17' CP) tuned to 14.074 MHz with an AT100M Pro.
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Thank you Stan and all who jumped in to offer advice. I am grateful. And smiling...
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--
Jim
VE4BWG

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