When the device is turned on, it shuts down after this error message. What could be the reason for this error?

Honestly I'm out of ideas.

I can't imagine why the Mac thought the Q was consuming too much power, as the USB on the QMX only uses the two data lines. No traces from the USB to anything else to my knowledge.

Any chance you tried the set-to-bootloader with the temporary jumper steps?

GREG

Excellent!

Tuning off Shapped tx did it!

?

Stan, thank you so much for your help.

Best 73, Bob

?

?

Sorry Nick i forgot to mention the plus.

1. Make sure that TxID is turned off.? Its timing is incompatible with QMX current tone detection, and QMX will drop tx in the pause between the TxID and normal modem signal (happens in many fldigi modes, not just RTTY) - probably a QMX firmware bug, it is on Hans list to fix.

2. In fldigi "Config - Modem - TTY - Tx" turn off "Shaped Tx".? This conflicts with QMX's own shaping algorithm, and causes it to drop transmit.

I hope that helps...

Stan KC7XE

I’m trying to use Fldigi RTTY and seeing the PTT dropping at the very beginning of transmitting text.

watching QMX output on my scope I see initial RF signal for less than a second and then output drops.?
I have configured Fldigi to use Hamlib with settings of PTT via hamlib command and RTTY is USB mode.

If I click on tune in Fldigi upper right corner, it enables PTT for duration that I keep it set.

I am sure this is a configuration issue but I don’t know what it is. Any ideas?

?

Thanks for any suggestions.

Bob, K3TCT

?

Even plugged in the QDX, waited until LED stopped flashing, plugged USB cable into computer and got "unknown device."

?

Yes, I did the v3a cut on the pc board. Not doing it I think would result in smoke and flames..har, har!

--

73
Karl
KI4ZUQ

Hello.

?

I am returning to ham radio after more than 40 years away. In order to regain some proficiency in CW I have purchased the device referenced in this URL. I am very pleased with it and it is a great assist for me. Plus it's fun. I offer this purely as an informational pointer. To clarify - I have no interest whatsoever in the marketing of this or other ham radio related devices.

?

?

--

73

Jim

VE4BWG

Just for information Hanz, the picture you sent appears to be for a QMX+ Version 1, not a QMX.?

--

73
Karl
KI4ZUQ

Is there a possibility that the bootloader is damaged?

The first few times i have seen the qmx drive come up but it was closed by the MAC due too much power.

At one time i tried to copy the new firmware but on that moment the mac closed again the USB port.

After that i see never the qmx drive again.

?

hanz

Hello Greg,

?

I am using rev 1.

The USB cables should be fully data i used them for my NanoVNA

i used Windows 10.

Tried also an older Mac with an older OS.

?

No luck so far.

73

hanz YL3JD?

Hello Greg,

Many thanks for your points, i check it tonight. Now at work :-)

?

Thanks 73 hanz

I have superficially similar behavior on 6m (QMX+ rev1).

?

But I have not gotten around to troubleshooting it since I don't use 6m too often.

Replacing the PCM1804 is beyond what I would normally consider as a try-and-see experiment but it may come to that.

Please share what you find out.

Thanks.

?

73, Mike KK7ER

?

Thanks Nick,

?

This is what i measured on JP104

See picture with the numbers at the measure points:

1. used as grnd

2. 6,9V

3. 7,7V

4. 1,14

5. 3V

6. ?0V

I hope this makes sense.

I feed the QMX with 8V

?

?

?

?

?

Good? morning Hanz

?

I've been watching this thread and have some comments and questions.

?

1) What revision is your QMX?

2) Are the USB cables you are using known to be fully data capable??

--- There are a LOT of USB cables out there that only deliver power and not data.?

--- You absolutely need USB cables that have the data lines included.

3) You mentioned you tried a windows PC. What OS level are you using. You made need a USB driver for pre-Windows 10.?

4) As others have noted, that amount of current seems to indicate that the QMX is in bootloader mode (no firmware installed - earlier revision QMXs require you to first load the firmware. Also, if not a 'newer' revision unit that had the firmware pre-loaded from the factory folks, there won't be anything on the LCD display.

?

5) So . . . in bootloader mode, you won't see a USB 'port' device. The QMX should appear as a Flash Drive.?

---On Windows, (depending on the OS version, etc) the flash drive may pop-up automatically or? . . .?

--- you may have to find the new 'drive' that appears in the Windows File Explorer and click on it to open the 'drive' window for copying in the firmware.

--- if you get that far, remember that you have to download the firmware and un-zip it. Then drag the file or copy and paste it into the flash drive window.

?

Then power cycle the QMX one more time.? If all goes well, the LCD should come up with a band selection showing. You might have to adjust the contrast pot to get the characters to show on the LCD.

?

here's a snip from the assembly manual.

?

On booting up for the first time, the QMX screen contrast adjustment will be required; QMX
will then ask you for your choice of version, use the right-hand rotary encoder to select the
version you built (for example 80-20m) then press the left button to select it. If you chose
the wrong band version, you can always get back to this selection using by executing a
Factory Reset. Please refer to the operating manual for further details.Rotate the right encoder (I think its the right - might be the left) until you get to the selection that matches the version you assembled.?

?

Hope this helps . . .

?

?

73 GREG? KI4NVX

?

?

?

Thanks Bruce and Ronan,

?

I was a bit confused by 74ACT08SC and 74ACT08SCX. One in SOIC-14NB and one in SOIC-14. Only a small difference in some geometrical parameters, but maybe important for QMX. So I remembered the post about an alternative IC.

?

Ronan, it was the MC74ACT08... MC74ACT08DG is in SOIC-14. That should be my choice.

?

73 Ludwig

Is the 3.3V VDD rail present Hanz?