Hi Paul
"Transmit enabled" means that you can? transmit. It? does not mean? you ARE transmitting. To transmit you press the T key.
Roger, I've been through the connections with a fine tooth comb, but no harm in doing it again., but it would be nice to know if "transmit enabled" should be permanently showing, as in my case, doesn't seem right.
Paul DJ0CU?
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Hello all.
Is there a way to simplify the OCXO adjustment if a thermometer (having a miniature probe) is available?
Is there a way to simplify the OCXO adjustment if a drift-free reference receiver (as obviously assumed) is not available?
Greetings
Jens
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Re: QMX - smoke - another C107/Q108 failure
Hi Razvan Thanks for your input - I meant only to rig up temporary linear supplies on my bench to check through the main-board, not as a permanent change The plan is :
- Remove both SMPS boards
- Supply +3.3 from linear regulator and check if the CPU runs
- Replace the 3.3V SMPS/linear regulator board and supply +12V from linear supply, check CPU again
- If all good, repair or replace the 5V SMPS board
Regards Rick Regards Rick
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Roger, I've been through the connections with a fine tooth comb, but no harm in doing it again., but it would be nice to know if "transmit enabled" should be permanently showing, as in my case, doesn't seem right.
Paul DJ0CU?
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Re: QMX, Song of praise, all 5 verses sung!
Thanks Axel
And I agree on all points! It IS a very fine thing :-)? ?
Short form:
- QMX ordered
- waited ( waited, waited, waited patiently)
- built, => firmware installed, => turned on, => running.
Once again confirmed, the kits from QRPlabs are great.
To fit so much RF technology into such a small space is quite a challenge.
Even for the experienced solderer.
But it is exactly as described in the assembly instructions in many places: Read carefully, some things twice, look closely with a magnifying glass, and take your time.
I took my time, but nevertheless I was done with the soldering after about 15 hours.
The installation of the firmware is really very simple. I only had to get a USB C cable.
7 Volt, 250 mA, take a deep breath and....
no smoke, no smell, everything wonderful, the little wonder box is running.
Antenna on and immediately signals on the 40m band.
Now the installation in the enclosure takes place.
Fine thing.
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New QRP-Labs product idea? A QMX/QDX based digimode / cat interface?
Important note : I know Hans is a very busy man doing great stuff for us, but the idea below came to mind this morning and had to write it down.
?
Not just owning QRP-Labs rigs?I have made my fair share of digimode and CAT interfaces for my other rigs.?
But playing with my QMX for a few days new and loving the single USB cable solution, the idea came to mind that it would be great to have a single USB cable digimode / cat interface for my other rigs.
And looking at the QMX and QDX basically everything is there :
- Built-in 24-bit 48ksps USB sound card (much better than most other USB sound cards)
- Built-in USB Virtual COM Serial port for CAT control (you could have one to configure the interface and one to pass through the rig).?
- The USB could be able to power the MCU etc.
Only thing missing is some good isolation for the audio and CAT signal lines, and a connector to which these signal lines would be available to the outside world.
If it would exist, I would immediately buy a 2 for my rigs.?
Just a though. And again, see?Important note?above.
--
73 Lex PH2LB?
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QMX, Song of praise, all 5 verses sung!
Short form:
- QMX ordered
- waited ( waited, waited, waited patiently)
- built, => firmware installed, => turned on, => running.
Once again confirmed, the kits from QRPlabs are great.
To fit so much RF technology into such a small space is quite a challenge.
Even for the experienced solderer.
But it is exactly as described in the assembly instructions in many places: Read carefully, some things twice, look closely with a magnifying glass, and take your time.
I took my time, but nevertheless I was done with the soldering after about 15 hours.
The installation of the firmware is really very simple. I only had to get a USB C cable.
7 Volt, 250 mA, take a deep breath and....
no smoke, no smell, everything wonderful, the little wonder box is running.
Antenna on and immediately signals on the 40m band.
Now the installation in the enclosure takes place.
Fine thing.
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Like you posted.
Thinking a bit more the things involved in Rx but not Tx are the
band pass filter components L401 and it's associated capacitors
and the trifilar transformer T401.
The sweeps in the diagnostics are useful to check, if they are
all giving a low max value that's an indication of a lack of
connection.? Check the soldering of the toroids, everywhere, it's
very easy to fail to get the enamel off.? I had this and redoing
the soldering fixed it.
Chris, G5CTH
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To put it another way, what does the same screen look like on a unit that is working normally in receive. Thanks
Paul DJ0CU?
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That's not transmitting, at least as
far as the software is concerned.
PTT signal and RF output are both off,
voltage isn't shown, BIAS SMPS is off.
Press T and you should see the
difference.
Chris, G5CTH
On 24/08/2023 07:56, Paul Harrison via
groups.io wrote:
toggle quoted message
Show quoted text
I have completed my QMX tx works fine on transmit but there is no
receive on any band.?
Attached a picture of the configuration screen. It looks like it's
permanently on transmit, what would be the cause?
Thanks anyone for tips.
Paul DJ0CU
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I have completed my QMX tx works fine on transmit but there is no receive on any band.?
Attached a picture of the configuration screen. It looks like it's permanently on transmit, what would be the cause?
Thanks anyone for tips.
Paul DJ0CU
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Re: #qmx Bringing up QMX, Nothing in display but terminal works, shutdown press does not
#qmx
Paul, maybe flashing your firmware, at that 180 mA limited current, was marginal for getting a good flash. Your startup delays, and failure to shutdown, sound more to me like software issues than hardware. Fingers crossed that something simple like a reflash, at normal voltage without current limits, and system reset, will normalize your QMX's startup and shutdown behavior.
toggle quoted message
Show quoted text
On Wed, Aug 23, 2023 at 10:12 PM, Paul - AI7JR wrote:
... I set my current to about 180 mA and it came up.
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Re: USB Device not recognized .... another one
#qmx
On Wed, Aug 23, 2023 at 09:18 PM, Rick Williams - VE7TK wrote:
?The LED backlight pot is at about 50%
Turn that backlight pot completely counterclockwise to start. Ideal contrast might be a hair off of full left, but anything beyond that is blank screen territory. 50% is definitely a blank screen. As Paul mentioned, you've got to give it more juice. 25mA is way too low.? I started mine with the 250mA and 7V that Hans recommended. When I saw things were working, I went up to 11V. And soon after that, I just put it on my LiFePO4, no problems for me operating at 13.3V and even more than that, through a properly matched balance line fed antenna.
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Re: #qmx Bringing up QMX, Nothing in display but terminal works, shutdown press does not
#qmx
Paul, I'm glad you got the screen fixed. No, those long delays are not normal. Do a system reset, and if that doesn't work, try re-flashing firmware followed by a system reset. If the problem still exists after that, then you have more troubleshooting. I think somebody else had similar startup delays and failure to shutdown.
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Re: #QMX Are these Issues?
#qmx
This isn't what I'd expect, my QMX
comes on instantly when I press the power on button. It shows the
Shut down message a fraction of a second after the long press but
doesn't close until I take my finger off, then it's instant.
Thinking a bit I wonder about the
controls board, try powering up with just the main board and PSUs,
no display, no controls. The current should remain at zero
indefinitely. If so you might try shorting pins 5 and 7 on JP201,
the connector to the controls board. That's the same as pressing
the power on button.
All these things seem to be associated with controlling things.
Chris, G5CTH
On 24/08/2023 06:06, Paul - AI7JR
wrote:
toggle quoted message
Show quoted text
Is there some kind of log for QMX issues? Don't want to bore
anybody by reporting what's known, or my build defect!
Here's what I'm seeing (I've got Firmware version 9 loaded,
7volts, 250ma current limit):
- On application of power, initial current is 0, but goes to
around 10ma after 10-15 seconds. Stays steady after it comes
up.
- On initial power application, power on click is ignored,
until the above 10ma step in current.
- At that point, power on click "delays" for ~10sec, then
display comes on and 150ma current draw.
- Tune knob frequency only goes up?
- Long press power click displays Shutdown, but LCD never goes
off, current (150ma) never drops.
- While "Shutdown" is displayed, band and mode can be changed!
- Going back to 3, if the power is interrupted briefly (maybe
200mS), device turns off. Pressing power-on click activates
immediately!
I what I'm seeing "normal" at the moment? :-)
Haven't gotten so far as to transmit or receive, either one. (Need
to read that operations manual!)
Please forgive if this is the wrong place to put this!
73, Paul -- AI7JR
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Re: USB Device not recognized .... another one
#qmx
Thanks for getting back Paul.
You are correct! In my case it should then trip the current limited supply. However, the QMX doesn't draw current at any time and never goes over my pre-set limit?
To confirm, when I apply power to the 2.1mm connector and long press the left encoder, the QMX should go into into Update mode whether it's connected to the PC via? USB cable or not?
--
73, Rick
VE7TK
Website:
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Re: USB Device not recognized .... another one
#qmx
Have I misinterpreted something. Some comments on this site
suggest that the QMX will turn on (no LED display) and draw
current (~150 mA) without a USB cable attached when the left
encoder is given a long push?
If you haven't loaded the firmware yet, it will come up in Update
mode--it won't wait for any key press. ;-)
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Re: USB Device not recognized .... another one
#qmx
25 mA is not enough. Hans suggests 250 mA and 7 volts
somewhere... I set my current to about 180 mA and it came up.
73, Paul -- AI7JR
On 8/23/23 21:18, Rick Williams - VE7TK
via groups.io wrote:
toggle quoted message
Show quoted text
Well I have completed my 12VDC QMX. I have it connected to a
current limited power supply set at about 25 mA at 9VDC (yes I'm
paranoid). I have a power meter and dummy load on the BNC output.
The LED backlight pot is at about 50%
I plugged in the USB cable BEFORE switching on the power supply
and immediately Win10 gave my the dreaded USB Device not
Recognized. When I switch on the Power supply no
current is drawn and there is 9 VDC on the power connector on the
PC board. Similarly a long push of the left encoder yields no
current drawn. (This is a good thing -- hi!)
I have tried 3 USB cables. Two get no reaction from my PC and one
gets the USB error message. None of the cables yield ANY reaction
on a Linux PC?
I'm not sure what's happening? I assume that applying power to the
QMX should cause it to enter and or display Update
firmware. Is a long press of the left encoder
required for that to be displayed? Is is displayed on the LED
display or on the computer?
The "flaky-ness" of the USB cables has me leaning toward a USB
cable problem some have encountered. I have successfully updated
the firmware on my QLG2 but it uses a different USB cable. So, am
I correct in assuming that -
- IF I have a faulty USB cable,
- the USB device will not be found,
- no bootloader will be installed,
- the backlight will stay off, and
- without firmware the QMX will draw no current?
Have I misinterpreted something. Some comments on this site
suggest that the QMX will turn on (no LED display) and draw
current (~150 mA) without a USB cable attached when the left
encoder is given a long push??
Finally, the USB-C connector on the main PCB looks a little dicey!
(Photo attached)
Thoughts appreciated. Thanks!
--
73, Rick
VE7TK
Website:
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#QMX Are these Issues?
#qmx
Is there some kind of log for QMX issues? Don't want to bore anybody by reporting what's known, or my build defect! Here's what I'm seeing (I've got Firmware version 9 loaded, 7volts, 250ma current limit):
- On application of power, initial current is 0, but goes to around 10ma after 10-15 seconds. Stays steady after it comes up.
- On initial power application, power on click is ignored, until the above 10ma step in current.
- At that point, power on click "delays" for ~10sec, then display comes on and 150ma current draw.
- Tune knob frequency only goes up?
- Long press power click displays Shutdown, but LCD never goes off, current (150ma) never drops.
- While "Shutdown" is displayed, band and mode can be changed!
- Going back to 3, if the power is interrupted briefly (maybe 200mS), device turns off. Pressing power-on click activates immediately!
I what I'm seeing "normal" at the moment? :-) Haven't gotten so far as to transmit or receive, either one. (Need to read that operations manual!) Please forgive if this is the wrong place to put this! 73, Paul -- AI7JR
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Re: QMX - smoke - another C107/Q108 failure
Hello Razvan
The SMPS boards are not a risky proposition, my friend. There is a known issue with a proportion of the current batch, having the Q103/Q104 drain short, regrettably. However other than this, there are no known issues with the SMPS boards or the whole concept.?
There are certain short-circuits, via solder bridges, carelessly placed probes, wire clippings and so on, which the QMX will not tolerate or forgive. However this is always the case in?any radio with multiple power rails. Well in fact in almost any circuit! You never have the right to short any arbitrary parts of the schematic together and expect the rig to not get damaged.?
On Thu, Aug 24, 2023 at 12:45?AM DL2ARL < dl2arl@...> wrote: Rick wrote above:
"I think the best approach here will be to rig up linear 3.3/5V supplies "
Hello Rick and group,
I have a similar tought on another thread in this group. Check for the message:
There already is a 3,3V linear regulator in the rig. One should only disable the "handover" from the linear regulator to the buck converter. I seriously intend to do so, at least until I understand what's up with all this happening that makes me feel rather unsure when handling the rig in so many experimental ways.
The rig is small and frail; my hands are big and clumsy... ;-)
For a 5V rail there is no such linear regulator in the rig, so one might add it somewhere where there is enough groundplane on the PCB to solder it to. I would refrain from using one of those scarry xx1117 5V LDO's needlessly having the output electrode on PIN 2 (middle pin) and the cooling tab. In case of a thermic failure, the input gets toasted directly to the output. Whoever designed this chip... (censored)
More civil linear regulators have the cooling tab connected to the ground electrode and if "melt-down" happens, the input gets connected to the ground and there might be hope that a fuse somewhere gets blown before the trace on the PCB burns out. But in most cases, the output stays safely isolated from the ugly happening.
And do not forget to connect the 3,3V regulator to the 5V rail, to avoid unnecessary loss. By doing so, there might be problems with the wake-up timing of the whole combo. As designed, the 3,3V rail feeding the main professor is alive and kicking long before the 5V rail is up. Reversing the order of wake-ups, some latch-up might occur that was not foreseen in the initial sequence. A big electrolitic cap here and there or even some sort of wise watch-dog reset-policy might be needed if wake-up gets bitchy.?
Let's try and please keep us informed of your progress. The more I think, the better I find the idea of replacing the buck converters with linear regulators, if not for good, at least for the testing period, until things settle down. But the more I think, the more I believe that, if I would succeed in replacing the buck converters with LDOs... I would just leave it stay put this way.?
It is also very refreshing to know that the buck converter boards can be tested without endangering the main professor, the one and only, the unreplaceable.
Yours friendly, Razvan dl2arl
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Lex PH2LB
Rick Williams - VE7TK
Paul - AI7JR