Hi KJ7YYM (another KJ7er!),
If you monitor this group e-mail server, Hans Summers at QRP Labs will post a message to let everyone know about two days ahead of time when the next batch of QDXes will be available for sale.? The fun typically starts at 0600Z on the Day of Infamy.? There will then be a a mad rush on the QRP Labs web page for the QDX on the appointed hour and day, where hundreds of hopeful hams will be attempting to out-click-and-type each other trying to order their very own kit.? It will all likely be over in under 15 minutes, if the initial offering is any indication.
On Fri, Nov 12, 2021 at 10:33 PM CALEB_ELI_3 via <CALEB_ELI_3= [email protected]> wrote: Hello to the group, I heard that QRP Labs will release another run of 350 QDX kits, and that I could find more information in the group.? I have not found that chat yet, so I would appreciate if someone could inform me on that.? Thanks!
73 DE KJ7YYM
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Re: QDX firmware 1.01c with aids for debugging no-transmit-RF issues
Hi Darryl...?
Yes I suppose (though please do test it first).?
Other ways could include just seeing VOX as PTT method in WSJT-X but leaving VOX disabled in QDX.
73 Hans G0UPL http://qrp-labs.com
-------- Original message -------- From: Darryl Hambly <darryl.hambly@...> Date: Sat, Nov 13, 2021, 8:25 AM To: [email protected]Subject: Re: [QRPLabs] QDX firmware 1.01c with aids for debugging no-transmit-RF issues Hans,
I noticed that you mentioned, "...and if you chose a key-up threshold which is higher than the key-down threshold, then this will stop transmission, it will always key-up regardless of the volume." ?Would this be an effective transmit inhibit?
This may be useful in cases where I would like to receive using an antenna that will not produce a safe SWR and protect from transmitting accidentally.
73
-Darryl W2DLH
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Re: QDX issues: please include info:
#qdx
Hey Stan,
Great to hear about your success with the QDX!
I'm really interested in that quad band EFHW... would you kindly share details?
--
Julian, N4JO.
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Hello to the group, I heard that QRP Labs will release another run of 350 QDX kits, and that I could find more information in the groups.io group.? I have not found that chat yet, so I would appreciate if someone could inform me on that.? Thanks!
73 DE KJ7YYM
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QCX 50W Amp - Low RF Output
#20m
Hi everyone:
Looking for a little help here.
My newly assembled 20m QCX 50W Amp is not playing nice. RF output is no more than about 9 Watts. This is with about 5 W input from the QCX+ (20m).
Supply voltage is 20 VDC regulated. Input DC current is 0.9 A on key-down.
This maybe a hint:
With the QCX+ in "Practice Mode" and with straight key selected and used, the key-up idle current of the amp is about 21 mA. With R5 fully CCW the key-down current is about 120 mA. When I now turn R5 CW, no rise in current is observed, until R5 is about 90% of its full CW travel. Is this normal or should I see the rise in current much sooner?
Any pointers to troubleshoot my amp are highly welcome.
73
KF6FOH
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Re: QDX issues: please include info:
#qdx
My feedback on the build and operation -
Bottom line - the QDX operation is awesome.? I built it yesterday and tested and operated it today on all bands.
I read the several recommendations and followed advise.? My biggest issue is my eyesight is not good up close so had to wear magnifying glasses.
It had been a while since I built a kit, but the manual was really good.
After construction, I did ohm checks to make sure no shorts, then powered up with a dummy load and operated on WSPR to measure TX power.? I used a 9V lithium battery for power and got +36 dBm or so on all bands.
I have an EFHW that covers the 80, 40, 30 and 20 meter bands with no tuner at better than 1.8:1 on the WSPR frequencies.? I had WSPR contacts from Alaska, Iceland, Hawaii and Venezuela - I live in Kansas (center of the USA).
Will try 80 meters tonight.
Kudos to Hans - I have used a CW carrier to generate a tone to a SSB receiver as a quick test, and that got me to thinking about the Siliconix chip as a digital SSB transmitter.? No need for that now as the QDX is there!
I ran the QDX with no cover and could not detect the transistors ever getting hot with finger thermometer.
Will update later if 80 meters has any issues.
Stan, AE0LM
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Re: QDX firmware 1.01c with aids for debugging no-transmit-RF issues
Hans,
I noticed that you mentioned, "...and if you chose a key-up threshold which is higher than the key-down threshold, then this will stop transmission, it will always key-up regardless of the volume." ?Would this be an effective transmit inhibit?
This may be useful in cases where I would like to receive using an antenna that will not produce a safe SWR and protect from transmitting accidentally.
73
-Darryl W2DLH
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Hello all, So I have my QDX all assembled and overall have been pretty happy with it other than some frustration trying to get it to work with a rasberry pi (which still doesnt work for me).? The issue I am noting is that while I get transmit current draws of 1amp no 30m .7amps on 20m I only get around .2amp on 40 m.? 40 m also has a receive signal of around 14db while 30 and 20 are both up in the 30db range.? I'm trying to figure out where I should start looking to get the power output of 40m up closer to where it should be along with its receive audio strength.?
??? v/r ?? K9WBZ
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Re: QDX Isues with sWindows10
#qdx
Hi Evan,
I am using my QDX on a windows 10 laptop without the issues you mention. I'm not sure if this is your start-up sequence but mine is: 1. USB cable hooked to windows 10 and the QDX but power to the QDX is off 2. Power on the QDX and wait until the LED goes solid 3. Start WSJT-X
The above works every time for me. Btw, I also disabled the USB 'power down' function in the power saver windows setting, but I'm not sure that matters.
I have seen twice now where the receive seems to go off on the QDX after some time and I'm not receiving any signals. Just switching bands and coming back will restore the signals. I'm not sure what that is about yet.
Cheers, Gregg W7GRM
On Fri, Nov 12, 2021 at 7:49 PM Evan Hand < elhandjr@...> wrote:
- Windows10 Home.?
- Firmware 1_01c.?
- Built for 12 volts operation
- Both Battery and switched DC
- Rev 1 Board
- One deviation: removing the 4 inductors before building the rest of the kit.?
I am having issues using my QDX with Windows10.? I have tried 2 different laptops from different manufactures.? I have not been able to get either one to work.? What is really strange is that after trying with a Windows10 PC I need to do multiple power off resets to then get the QDX to work again with my Raspberry Pi 4 running 32 bit Buster with all updates.? The tests are with version 2.52 of WSJT-X in both environments.? The terminal software that I use is PuTTY on both.? Putty will always connect.? The sound cards will disconnect at times between reboots.
There appears to be something that happens when connecting to a Windows10 USB port that does not happen with Linux as installed on a Raspberry Pi 4 with 8 GB of memory.? It seems to be repeatable on one of my Windows10 PCs:
1 I confirm that the QDX is working both receiving and transmitting on the Raspberry Pi
2 I power all down and move the USB connections to the Windows10 PC
3 Turn on the QDX and the level bar of WSJT-X is much higher than with the Raspberry Pi
4 There are no decodes
5 Shutdown again and reconnect to the Raspberry pi
6 First time on powering up the QDX the terminal window will work, the WSJT-X will not receive audio.? The transmit function will work with the Tune button
7 Power cycle the QDX again and this time or the next power cycle the QDX will start receiving signals and send them to the Raspberry Pi to be decoded.
8 Going back to the Windows PC starts the issues all over again.
The other Windows10 PC used to connect but now will not connect either the comm port or the USB sound devices.
The QDX has been performing well on the Raspberry Pi 4, though do want to use it with the faster Windows10 machines.? Both are laptops.? My speculation at this point is that a windows startup process for the USB device is causing an issue with the update process of the QDX.? That might explain the multiple restarts that are required, in that Windows may be putting something on the disk that gets interpreted as an update that has to be processed to determine it is not a file for the QDX to use.? This is pure speculation at this time and maybe WAY off base.
?
I guess my next step is to try to capture any issues with logs on all three devices.? That will be a task for tomorrow.? Calling it a night tonight.
The question to the group is if anyone else is experiencing similar issues with Windows10?? Has anyone tracked down the issue?
73
Evan
AC9TU
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QDX Isues with sWindows10
#qdx
- Windows10 Home.?
- Firmware 1_01c.?
- Built for 12 volts operation
- Both Battery and switched DC
- Rev 1 Board
- One deviation: removing the 4 inductors before building the rest of the kit.?
I am having issues using my QDX with Windows10.? I have tried 2 different laptops from different manufactures.? I have not been able to get either one to work.? What is really strange is that after trying with a Windows10 PC I need to do multiple power off resets to then get the QDX to work again with my Raspberry Pi 4 running 32 bit Buster with all updates.? The tests are with version 2.52 of WSJT-X in both environments.? The terminal software that I use is PuTTY on both.? Putty will always connect.? The sound cards will disconnect at times between reboots. There appears to be something that happens when connecting to a Windows10 USB port that does not happen with Linux as installed on a Raspberry Pi 4 with 8 GB of memory.? It seems to be repeatable on one of my Windows10 PCs: 1 I confirm that the QDX is working both receiving and transmitting on the Raspberry Pi 2 I power all down and move the USB connections to the Windows10 PC 3 Turn on the QDX and the level bar of WSJT-X is much higher than with the Raspberry Pi 4 There are no decodes 5 Shutdown again and reconnect to the Raspberry pi 6 First time on powering up the QDX the terminal window will work, the WSJT-X will not receive audio.? The transmit function will work with the Tune button 7 Power cycle the QDX again and this time or the next power cycle the QDX will start receiving signals and send them to the Raspberry Pi to be decoded. 8 Going back to the Windows PC starts the issues all over again. The other Windows10 PC used to connect but now will not connect either the comm port or the USB sound devices. The QDX has been performing well on the Raspberry Pi 4, though do want to use it with the faster Windows10 machines.? Both are laptops.? My speculation at this point is that a windows startup process for the USB device is causing an issue with the update process of the QDX.? That might explain the multiple restarts that are required, in that Windows may be putting something on the disk that gets interpreted as an update that has to be processed to determine it is not a file for the QDX to use.? This is pure speculation at this time and maybe WAY off base. ? I guess my next step is to try to capture any issues with logs on all three devices.? That will be a task for tomorrow.? Calling it a night tonight. The question to the group is if anyone else is experiencing similar issues with Windows10?? Has anyone tracked down the issue? 73 Evan AC9TU
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Re: QDX - trifilar toroid T2
Just found that on the schematic. Thanks Julian. Guess I'm still in business..... off to the LED install..... grin
Jim W3APC
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Re: QDX firmware 1.01c with aids for debugging no-transmit-RF issues
Exactly as Shirley says, of course.
The reason why that is so is because the firmware is handled as one single block of data that completely overwrites the one it replaces, unlike PC software, where there may be hundreds of individual files, and where an update may be achieved by changing as few as one of them.
--
Julian, N4JO.
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Re: QDX - trifilar toroid T2
Good for you for checking!!
Your reward for being so attentive to detail is that it's OK: two of the windings form the centered tapped secondary of a transformer, so they are in series once soldered to the circuit board. The third winding should be isolated, though.
--
Julian, N4JO.
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Re: QRP sub-bands for FT8
Currently digital modes are only allowed in the CW band segment. And I think that's the correct home for narrowband digital modes, ones that use 500 Hz or less for an individual transmission. FT8 is such a mode; each signal only uses about 50 Hz. It uses an entire voice channel worth of bandwidth because it's popular, with many stations sharing that 2.8 kHz piece of the band; it's more closely packed than CW operation is.
An FCC proposal would allow digital modes with unlimited data rates and no bandwidth limitation, still in the CW band segment. In theory you could create a mode that used the ENTIRE CW segment to achieve data rates in the?hundreds of kb/second, perhaps using OFDM and adapting to interference. The ARRL countered with a proposal that would limit bandwidth to 2.8 kHz, but again with unlimited data rates.
I think that would be a horrible mistake because wide and narrow modes don't mix well. If we're going to widely authorize modes with SSB or wider bandwidth, those belong in the voice segment.
No hope they will put the next FT-8 sub-band in the voice bands I suppose?
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Worked on the kit today and ran into a short at T2.?? THE Trifilar Torrid off the board read good for continuity. (A-A etc) Installed in the board and now reads shorted A to B. Solder joints look ok. Any ideas? Guess i am going to have to pull T2.?
Got a sneaking suspicion its not in the winding...
Jim
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Re: QDX - No RF output, Tx line stays low
I finished the QDX today and experienced the finals failure. Wound the transformer for 12 volts, used a LIOn battery at 12.2 volts. Receive worked incredibly well. Transmit tested with a dummy load. Output was about 1 watt on 20 m and 40m but no output on 80. I measured the voltage on the finals and was 12 v on all in receive. Next time I transmitted there was no power and that ominous smell started being emitted. A visual inspection found that R37 was missing. Apparently knocked off rather than unsoldered by mistake. I¡¯m not sure a bypass capacitor would have that much effect on output power or failure. I will disconnect the 12 v feed to the finals and see if the IC5 is also dead.? Conditions: 12 ?v? Win10 Wsjtx Stock firmware?
-- Jginaz
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Re: QDX firmware 1.01c with aids for debugging no-transmit-RF issues
No need to install them in order. You can go directly to the newest one.
On Fri, Nov 12, 2021 at 6:11 PM Mike - N5AQM < n5aqmdb@...> wrote: Is it safe to assume that these firmware updates are not incremental? I plan on starting my build soon and would like to just upload the latest. (I have had updates for other gear where you need to run thru them all with the oldest to the latest)
Thanks!
73
-Mike
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If you have a QCX without the TCXO option, it can be a bit off frequency out of the box. The 27 MHz crystal for the Si5351A is an inexpensive microprocessor crystal and its frequency is not guaranteed to be highly accurate. It's usually a little bit above 27 MHz; the default setting of the reference frequency is actually 27.004000 MHz, 4 KHz above the nominal frequency.
The firmware lets you set the actual reference frequency of the crystal in your QCX to get a more accurate frequency readout. (It uses that value to calculate the correct settings of the frequency synthesizer.) You can find the correct setting?in one of a few ways. If you have one of the QRP Labs GPS modules, you can use it to automatically set the frequency. If you have a frequency counter, you can measure the output frequency of your QCX, calculate the error, and then adjust the reference frequency accordingly. If you have a calibrated signal generator with a precise output, you can zero beat it with your QCX, and again calculate the error and adjust. You can set it in increments of 1 Hz, which is 0.037 ppm, a negligible error. (At 10 MHz, that would be a maximum error of 0.37 Hz. There are very few ham applications that require higher frequency accuracy than that. And it's going to depend somewhat on temperature in any case, so even if you set it to maximum accuracy on the test bench it might be a bit farther off when you operate the radio.)
The procedure for setting the reference frequency is now in the QCX operating manual, which is separate from the QCX construction manual. it's on page 35 of the manual for firmware 1.07. The procedure for calibrating using the GPS module is on page 36.
If you have the TCXO, the reference frequency needs to be set for 25.000000 MHz. The TCXO is specified as being accurate within 0.5 ppm, which would be an error of 5 Hz at 10 MHz. You can use the calibration procedure to set it more accurately if you wish, but most operators will find it unnecessary. If you do it, set it to 25 MHz manually first and THEN run the GPS calibration.
Your reports from the RBN suggest that your QCX is about 50 ppm off from the default value. You didn't report whether your frequency is high or low. adjusting the reference frequency down 1.35 kHz (to 27.002650) if your frequency is high, or up 1.35 kHz (to 27.005350) if your frequency is low, should get you much closer. That amount of error is normal for inexpensive crystals; there is nothing wrong with your radio, and it's why the adjustment is there. A more tightly specified crystal might cost 10 times as much and require a price increase of the rig.
It's also possible that the frequency accuracy of the RBN is less than perfect. Using GPS calibration is the best way to get the rig calibrated accurately if you have the GPS receiver for the QCX.
I noted on my QCX, that the QRG is off from what RBN indicates.
15 m 1 khz, 20 m 0,6 to 0,7 khz, 30 m 0,4 - 0,5 khz, 40 m 0,3 khz and 80 m 0,2 khz.
Any ideas why? and how to correct that?
73s
Martin
DK3UW
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Re: QDX firmware 1.01c with aids for debugging no-transmit-RF issues
Is it safe to assume that these firmware updates are not incremental? I plan on starting my build soon and would like to just upload the latest. (I have had updates for other gear where you need to run thru them all with the oldest to the latest)
Thanks!
73
-Mike
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Re: QDX - No RF output, Tx line stays low
I installed firmware 1.01c, see the diagnostic flashing. ?One flash in PTT test, two in Tune in WSJT-X. ?Received signal level shows 80 on the bar graph, but now I don't decode anything. ?Went back to v1.01a, decoding again. ?Enough for one day!?
73, Ben. K0IKR
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Julian N4JO
Darryl Hambly
Zachary Painter
Jim
Shirley Dulcey KE1L