About stopping ModemManager. The service can be stopped and disabled, but it can still be started again by other dependencies. If you mask the service it should never start again. You can always unmask the service to start using it again.

If you are never going to use 4G/LTE modems (USB sticks or built into laptops). This is the easier solution.

About masking and unmasking in the systemctl man page:

mask:
This will link these unit files to /dev/null, making it impossible
to start them. This is a stronger version of disable, since it
prohibits all kinds of activation of the unit, including enablement
and manual activation. Use this option with care.

unmask:
Unmask one or more unit files, as specified on the command line.
This will undo the effect of mask.

# systemctl disable --now ModemManager.service 
Removed /etc/systemd/system/multi-user.target.wants/ModemManager.service.
Removed /etc/systemd/system/dbus-org.freedesktop.ModemManager1.service.

# systemctl mask ModemManager.service 
Created symlink /etc/systemd/system/ModemManager.service → /dev/null.

On Mon, Nov 15, 2021 at 01:44 AM, syuji ota wrote:

However, when the Linux or Windows systems sends <CR> without user permission,

QDX goes into terminal application mode and USB audio is stops.

If so, can you change the command to enter terminal application mode?

This is interesting, but I was able to enter the QDX menu system while watching the spectrum with baudline, and the audio never stops when I pressed enter and entered the menu. Was also able to send CAT commands, the audio only changes when going between RX/TX.

I checked with the following commands:

serial console:
minicom -D /dev/serial/by-id/usb-QRP_Labs_QDX_Transceiver-if00 -c on

baudline:
parec --format=s16le --channels=1 --latency-msec=5 | ./baudline -stdin

Sorry, I meant to write George in the previous email, apologies it has been a long day!

Best regards, Peter.

Hi Twolane,

I will take this off your hands if you still have it, shipping is to Sanibel FL.

Thanks!

Best regards, Peter.

Hi all,

So far it’s been a fun project to build and have appreciated everyone’s tips and gotchas.?
And of course enjoyed Hans’ photos of his tech assistant.

Order# 50083

OS: RPi4 (Buster)

FW: was trying to install 1.01c from original shipped fw.

PWR: built for 12V (3:2), was using 9V battery as input for initial testing

PCB: Rev1
PCB placement: not in case, just sitting on table

Build deviations: removed SMD inductors as first item so PCB could sit flat before installing topside components. Build was straight forward except for the replacement inductors was messy.

?

Downloaded 1.01c to RPi and unzipped file. (119.5K)

Inserted 9V battery for pwr, LED blinks properly. Using Putty, successfully connected via USB from RPi4 into QDX on port /dev/ttyACM0 and was able to access the QDX.

First thing to do, update the FW to latest release before doing anything else.

In menu, selected “Update Firmware”, LED blinks slowly, brings up file manager similar to page 80 of manual v1.06. Dragged/dropped file 1.01c into the area window.

It brought up another window to show the transfer, but everything just stopped without transferring anything. LED went dark, and USB connection dropped. No magic smoke.

I’ve tried applying power multiple times, but no blinking LED, etc. and no USB comms. I checked both AMS1117 and they are putting out their required voltages. I don’t have fine diagnostic probes to check VDD on the processor or other SMD components without wreaking havoc.

Any thoughts what I did wrong and how to get it back to life?

thanks, 73,

.paul. VA3FUZ

firmware: 1.01c
OS: Ubuntu 20.04.3
xfrmr: 3:3 9v
power: 2S Li-ion ~8v
deviations:
1) went overboard with the magnet wire allowance and came up short on T2, so the B wire is from the scrap bin. No reason to expect it matters, except I had to scrape it the insulation.
2) no case. Still in my pcb vice

Here are my RF sweeps. Not pretty & not sure what's going on. I'm thinking to remove the first turn from L12 to shift the peaks up, but I don't think that will help the numbers or 20m.






–Brent WT4U

开云体育

Hans,

the issue with Linux arises because the QDX presents its serial interface as a modem, or in emulation-speak possessing the Abstract Control Model (hence the /dev/ttyACM0 designation, rather than the more frequent /dev/ttyUSB0). These days dial-up modems are a rarity, but wireless modems, such as for GSM, 3G &c. are in common use.

Rather than the drastic hack of disabling the Modem Manager, which may be needed to support other hardware, Ben's (PA2ST) suggestion (/g/QRPLabs/message/74652) of using a udev rule is a very sound & reliable solution.

Much other SDR kit requires one or more udev rules under Linux.

HTH, 73, Stay Safe,

Robin, G8DQX

I have seen WSJT-X report clipping input audio (and no sensible reception) when first loaded up (QDX solid led before launching WSJT-X) on all versions of firmware (at least b and c but pretty sure it happened before too). I have a feeling it could be a related issue.

Closing WSJT-X and repowering QDX has fixed the issue each time. My hypothesis is that it happens when I launch WSJT-X almost immediately after the led lights solidly but I haven't had time to confirm this or whether only reloading WSJT-X is sufficient.

Running 9V, haven't looked at the serial traces for optimisation yet. Had plenty of QSOs on all 4 bands within Europe, one transatlantic to USA so QDX seems to be working great (note my antenna is a horrible compromise for now).

Modifications from standard: blew the PA up twice, first time noticed immediately and replacing 4 BS170s resolved the issue. Second time had to replace the 74ACT08 too (used TI SN74ACT08) but my transatlantic contact was post these mishaps. Pretty sure both times was due to tuning errors, I am now using an LER SWR resistor bridge type circuit during tuning and no troubles since.

(MS Windows 10, linear PSU @8.something volts)

Just thought I'd give you my observations in case they help.

73
Jack

On Sat, Nov 13, 2021 at 05:40 PM, Julian N4JO wrote:

Yes, it certainly shows you what the orientation should be when properly installed, but unfortunately you can't solder it in that way, because you can't get to the underside of the board. The precision of the kit parts is really good, so if you go for parallel you can't really go wrong.
--
Julian, N4JO.

I connected the BNC to the rear panel then solder the BNC and use the panel to align the remaining connectors.? I did not mount the back to the bottom or top.

Dave, he will be rewarded.? Assuming we are successful, the QDX will be his.? : )

73,? Mike KK7ER

On Sun, Nov 14, 2021 at 01:47 PM, Hans Summers wrote:

I wonder, is it just the 1.01c firmware that doesn't initiate correctly every time? Or all firmware versions??

I had issues with 1.01a as well.? 1.01c seems to be better, although I now know how to get around the issue.? I did not install 1.01b.

73
Evan
AC9TU

Had the same issue, resolved it by filing a bit of the opposite long side of the PCB. Just a fraction of millimeter was enough. I even managed to put a piece of paper (would have used kapton tape if I had any) just in between the IC and the chassis to prevent any possible short.?

Additional on. Previous post regarding ATU 10,, mini-tuner. My tuner worked very well for the first 2 weeks. I am sad to report it stopped tuning and appears to be broken.? When opended up, the construction great, sealed in clear silicone, but no ?repairable problem. To be honest, I loved it so much, I ordered a replacement, but you may want take care.?

It may be the case that this does not resolve all the CAT control issues, but it certainly resolved mine :)?
--
Karl Heinz - K5KHK

My name is Julian and I approve of this message ;-)
--
Julian, N4JO.

Finished QDX today and fired it with? Windows 10 and made two nice contacts.? Learned a few tricks in the process.

1.? Connect QDX and allow time for device to connect before opening WSJT.? This allows WSJT to see the QDX as an option
2.? Open control panel then sound then select QDX? set Record Levels to 85 and output levels to 90.
3.? If you are having issues, use the configuration editor in terminal mode to check the hardware and CAT controls.?
4.? Use configuration menu to update firmware to 1.0c as the blinking LED is a great debugging tool. ( Thank You Hans).

On Sun, Nov 14, 2021 at 08:06 AM, Dave Edwards wrote:

I only just finished my Small Wonder Labs PSK31 kit.

I remember putting together a couple of Dave's kits years ago, and I really thought the rock-bound kits, with no display, were something.? I was on the air on 7030 for well under $100!? That's why I consider the QCX line such an engineering marvel.? So much consideration and functionality, especially at the economical price.? Full band coverage, a display, built-in alignment, and options galore.? My KX1 is great (I use it much more than the K1), but it was a $500 kit for two bands (20m and 40m), and it cost another $100, if I recall correctly, to get 30m and 80m, and that may not have included the ATU.? And considering some of the alternatives - Four State QRP kits, QRPMe (carrying on Dave's RockMite line), Diz's OneWatter and other kits, Pacific Antenna / Hendricks kits, and many others, I would say we are getting enormous value and a well-designed, beautifully-engineered kit from Hans.? The QCX-Mini display board set up is a work of art, in my humble, non-engineering opinion.? haha.

Your post is a nice reminder of how things were in the not-so-distant past.?

A more specific way would be to add a udev rule that let ModemManager ignore this specific device. For example based on the USB ID.

With lsusb I found the ID:

lsusb?-vt
<snip>
??????????? |__ Port 4: Dev 12, If 4, Class=Audio, Driver=snd-usb-audio, 12M
??????????????? ID 0483:a34c STMicroelectronics 
??????????? |__ Port 4: Dev 12, If 2, Class=Audio, Driver=snd-usb-audio, 12M
??????????????? ID 0483:a34c STMicroelectronics 
??????????? |__ Port 4: Dev 12, If 0, Class=Communications, Driver=cdc_acm, 12M
??????????????? ID 0483:a34c STMicroelectronics 
??????????? |__ Port 4: Dev 12, If 3, Class=Audio, Driver=snd-usb-audio, 12M
??????????????? ID 0483:a34c STMicroelectronics 
??????????? |__ Port 4: Dev 12, If 1, Class=CDC Data, Driver=cdc_acm, 12M
??????????????? ID 0483:a34c STMicroelectronics
</snip>

So the VID/PID for the QDX is: 0483:a34c.

Then, create the following rule and reload udev.

# create UDEV rules (as root)
cat > /etc/udev/rules.d/80-qdx.rules << 'EOF'
ATTRS{idVendor}=="0483", ATTRS{idProduct}=="a34c", ENV{ID_MM_DEVICE_IGNORE}="1"
EOF

# Reload udev rules
udevadm control --reload-rules && udevadm trigger

You can show info to see if udev added the ignore tag (ID_MM_DEVICE_IGNORE=1) for ModemManager.

udevadm info /dev/ttyACM0
P: /devices/pci0000:00/0000:00:01.2/0000:02:00.0/usb1/1-2/1-2.4/1-2.4.4/1-2.4.4:1.0/tty/ttyACM0
N: ttyACM0
L: 0
S: serial/by-path/pci-0000:02:00.0-usb-0:2.4.4:1.0
S: serial/by-id/usb-QRP_Labs_QDX_Transceiver-if00
E: DEVPATH=/devices/pci0000:00/0000:00:01.2/0000:02:00.0/usb1/1-2/1-2.4/1-2.4.4/1-2.4.4:1.0/tty/ttyACM0
E: DEVNAME=/dev/ttyACM0
E: MAJOR=166
E: MINOR=0
E: SUBSYSTEM=tty
E: USEC_INITIALIZED=5869499
E: ID_BUS=usb
E: ID_VENDOR_ID=0483
E: ID_MODEL_ID=a34c
E: ID_PCI_CLASS_FROM_DATABASE=Serial bus controller
E: ID_PCI_SUBCLASS_FROM_DATABASE=USB controller
E: ID_PCI_INTERFACE_FROM_DATABASE=XHCI
E: ID_VENDOR_FROM_DATABASE=Advanced Micro Devices, Inc. [AMD]
E: ID_PATH=pci-0000:02:00.0-usb-0:2.4.4:1.0
E: ID_PATH_TAG=pci-0000_02_00_0-usb-0_2_4_4_1_0
E: ID_VENDOR=QRP_Labs
E: ID_VENDOR_ENC=QRP\x20Labs
E: ID_MODEL=QDX_Transceiver
E: ID_MODEL_ENC=QDX\x20Transceiver
E: ID_REVISION=0100
E: ID_SERIAL=QRP_Labs_QDX_Transceiver
E: ID_TYPE=generic
E: ID_USB_INTERFACES=:020201:0a0000:010100:010200:
E: ID_USB_INTERFACE_NUM=00
E: ID_USB_DRIVER=cdc_acm
E: ID_MM_CANDIDATE=1
E: ID_FOR_SEAT=tty-pci-0000_02_00_0-usb-0_2_4_4_1_0
E: ID_MM_DEVICE_IGNORE=1
E: DEVLINKS=/dev/serial/by-path/pci-0000:02:00.0-usb-0:2.4.4:1.0 /dev/serial/by-id/usb-QRP_Labs_QDX_Transceiver-if00
E: TAGS=:uaccess:systemd:seat:
E: CURRENT_TAGS=:uaccess:systemd:seat:

73, Ben
PA2ST