Doug,
Are you sure that clock is your problem? I've tested MacBook Pro many times and it's very accurate. Has never affected decoding. I don't have an iMac so maybe it's different, but I would doubt it.
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On Nov 17, 2022, at 11:26, Doug Kaye < doug@...> wrote:
The clock on my iMac isn't accurate enough to reliably decode FT8, etc. Can my qgl2 solve this? Can it control the time on the iMac or should I connected it to the QDX? So far, I haven't been able to communicate with it on the iMac via a terminal emulator since I haven't been able to identify the serial port in /dev.
?
? ? ?¡doug K6DRK
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The clock on my iMac isn't accurate enough to reliably decode FT8, etc. Can my qgl2 solve this? Can it control the time on the iMac or should I connected it to the QDX? So far, I haven't been able to communicate with it on the iMac via a terminal emulator since I haven't been able to identify the serial port in /dev.
?
? ? ?¡doug K6DRK
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Re: Possible Rev 5 Suggestion - Multicolor LED
Hi Mitch
I take your point about the multi-colours being easier to read.?
In some way though all the QRP Labs products have always been quite minimalist in their user interfaces. From the Ultimnate3S, to QCX, QDX, the number of controls and display elements has always been relatively?small. They all pack lots of features and performance, with a small number of user controls.?
Perhaps there are other ways to solve the counting to 3 problem. If ordinary correctly functioning transmit operation was for example, represented by a pulsating appearance of the LED? So it sort of fluctuated slowly at 1Hz from 0 to full brightness and back, if all was well - that would be quite distinct. But if an error condition needed to be indicated, then use 1 flash or 2 flashes - much easier to discriminate?between.?
This could be done on the existing hardware with no need a new version with?multi-colour LED.?
On Thu, Nov 17, 2022 at 4:07 PM Mitch Winkle < ab4mw@...> wrote: It can (for some) be difficult to count the flashes as well.? I have struggled with this depending on lighting conditions and radio positioning.? Three flashes fools me into believing it's two flashes and then I have to stop everything to carefully count.? Blue Power, Red TX means low audio, and?Green TX means all is well!? Something like that maybe?? The user wouldn't even have to focus on the device, only note the color change.
In the meantime, reducing the LED brightness may make the flashes easier to count also.
It's nice to catalog things like this for later revs.? They aren't show-stoppers but they make the device more user-centric for some lines of code to set GPIO levels (I'm sure it's a bit more than that ;) ).
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Re: QSX Stuck in Firmware Update Mode
Well, that will sure cause a problem!? Glad it's figured out.
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3 QDX projects for someone.
I have 3 QDX radios none of which work. #1 and 2 are finger burners if held on the bottom but I did make a few contacts with 2 before it died. #3 (in an enclosure) performed well for six months and now joined the others.There is a lot of talent here and maybe someone is looking for a challenge, I for one have given up kit building
.? Solder technique is good. If interested or have questions let me know. Dave W9DBF.
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Re: No Serial Port? (QDX on Mac OS)
#qdx
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On Nov 17, 2022, at 10:11, Doug Kaye < doug@...> wrote:
Please ignore this thread and my others. Hans has helped me figure out all my problems, I think. The EEPROM is missing from the PCB! Thanks for all your help and advice. I've learned a lot along the way.
?
? ? ?¡doug K6DRK
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Re: QSX Stuck in Firmware Update Mode
Please ignore this thread and my others. Hans has helped me figure out all my problems, I think. The EEPROM is missing from the PCB! Thanks for all your help and advice. I've learned a lot along the way.
?
? ? ?¡doug?K6DRK
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Re: No Serial Port? (QDX on Mac OS)
#qdx
Please ignore this thread and my others. Hans has helped me figure out all my problems, I think. The EEPROM is missing from the PCB! Thanks for all your help and advice. I've learned a lot along the way.
?
? ? ?¡doug K6DRK
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On Thu, Nov 17, 2022 at 06:18 AM, Mitch Winkle wrote:
How does it behave on 12V?? Or can it?? I am not familiar with the circuit.
?
Thinking of a portable scenario where invariably power is 11V - 13.8V nominal.? Thus, if the amp performs at a lower output (on 12V) then all good.? The amp stays cooler and should be able to survive a higher duty cycle.
?
What are the issues with this thought process??
?
Hi, Mitch.? The amp puts out about 25w with 12v.? I was running my other amp (40m) that way for quite a while with the QDX and it was fine.? Then I purchased the boost converter you see in the photo and started running it at 20v.?? Issues? 1. Building the LPF kit, the LPFs come with components for 5w operation so I had to order higher power components.? I increased the toroid size to T50 and the capacitors to 250v varieties.?? 2. When designing my LPF switching circuit off the QDX with an Arduino Nano and buck converter, I created a ground path through the STM32 on the QDX and cooked its LPF pins.? I actually did this on both my QDXs.? I switched to a transistor driven LPF switch circuit.? The most current the 2n2222 transistors can sink of the STM32 is 7mA through a 470 ohm resistor. 3. My DC jack on the amp is a little funny and if it isn't just right, it gets intermittent power.? I can see that on my boost converter screen.?? Really, that's it.? I still need to print a case for the LPF board and switching board. Joshua
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Re: PTT change for 50 W amp.
On 17/11/2022 15:19, Ronald Taylor wrote: I think you need to be looking at manual Rev Someone else asked a similar question earlier. The revisions are listed here read carefully:-) 73 Alan G4ZFQ
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Re: QDX for 40-10m - Should I wait?
#qdx
That's exactly what I am going to do buy both options. Just let me know when the hi band kit is ready and the order will be in. If Hans is taking advanced orders just let me know.
Dean
N2TNN
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Re: PTT change for 50 W amp.
I think you need to be looking at manual Rev 1.07 for your PCB Rev. 3 board
Ron
On Thu, Nov 17, 2022 at 8:09 AM < ha7rja@...> wrote: The drawing of the JP21 and JP22 layout at the top of page 101 of the QCX+ assembly manual (rev. 1.04) is NOT the same as the PCB of my QCX+ (PCB rev 3).
The drawing reads (left column, from top JP21 to bottom JP22) reads "+5V, Ring, PTT, Tip", whereas the PCB reads "PTT, Ring, +5V, Tip". This is VERY confusing!
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Re: #gdx QDX Firmware Request: Phase Modulation (psk31, etc.)
#gdx
Hello Ed
The attached picture shows a PSK 31 signal. A 1 is represented by a 0-degree phase shift and a 0 is represented by a 180-degree phase shift. Each symbol generation has a raised cosine shape. The phase change occurs at the zero amplitude point. This fact ensures that the bandwidth occupation of the mode is only 31Hz.
QDX could create the 180-degree phase changes. However it cannot produce the raised?cosine envelope shape because QDX does not have any way to control the RF envelope amplitude. It's all or nothing. If you did phase shifts at intervals of 1/31 seconds the result would be a much wider signal than the desired 31Hz. This is why people are telling you, correctly, that this cannot be done on a QDX.?
On the other hand - there is another interesting possibility. This article is of interest:?
It notes that a string of 1's is a single unmodulated carrier. A string of 0's has the appearance viewed in the frequency domain of TWO carriers at?+/- 15.5Hz from where the unmodulated carrier was (half the symbol rate). In the article the author discusses generating the necessary signals using two oscillators which are set either to the same frequency, or at?+/- 15.5Hz (above and below it). he states that as long as the frequency separation and timing is perfect, there is no need for envelope shaping.?
Why this is relevant for the QDX is that the QDX in fact does contain two oscillators (in the Si5351A). And each of these two oscillators is connected to its own pair of BS170s which amplify with the transistors operating in Class-D (arguably). Ordinarily, the two sides are set at the same frequency and at 180-degree phase amplitude; the output transformer adds up the two parts (well arguably subtracts), putting them together to produce the desired output power.?
So then what if you set the two oscillators to 7039984.5 and 7040015.5 Hz. Wouldn't you get two equal amplitude distinct tones at?+/- 15.5Hz (31Hz separation)? If any other unwanted frequencies would be generated (other than RF harmonics) then what would be the mechanism for generating those??
I suspect there is something wrong with the idea... but can anyone explain what exactly?
73 Hans G0UPL
Many thanks for the comments Robin & Allison,
G3PLX assumes audio frequency generation of the phase shift.
By generating the FT8 type frequency shift directly at RF it seems that the QDX is able to remove harmonics by using the RF low pass filters, rather than an audio frequency low pass filter and the linear following stages of SSB generation.
This is a brilliant system, one reason I got a QDX, for the idea alone, not because I particularly wanted to FT8 on 40m? :-)
(still interesting to try it out though)
Currently the QDX does not have the software ability to create a direct RF phase shift modulation, so psk31 is not possible, as Allison says.
However the Si5351a can be programmed to create a phase shift directly at RF.
In this case, perhaps the harmonics might also be removed by the RF low-pass filters, in the same way as for FT8.
("amplitude management" was definitely not the right way of expressing myself !)
Yes, i came up with this request due to seeing the post about FLDIGI, not sure what Mitch is doing, but I joined that group anyway :-)
Regards,? Ed? G8BQR
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Re: PTT change for 50 W amp.
The drawing of the JP21 and JP22 layout at the top of page 101 of the QCX+ assembly manual (rev. 1.04) is NOT the same as the PCB of my QCX+ (PCB rev 3).
The drawing reads (left column, from top JP21 to bottom JP22) reads "+5V, Ring, PTT, Tip", whereas the PCB reads "PTT, Ring, +5V, Tip". This is VERY confusing!
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Re: What PC are You using for QDX?
On 11/16/22 22:56, ve3ega wrote: Neil,
Yes, I am looking forward to receiving mine. Michael at "Inovato" sounds like a nice guy!
Looking forward to trying it out for WSJT modes and reporting back here! +1 I will be looking for advice on which version of WSJT to use and how easy it is to install - I'm rusty on Sudo apt get type commands lol!
73 NP on the sudo, I can help there. I live on the command line. :-) There are a few tricks so you can run the X applications remotely. I can run wsjt-x on the Pi (clone) and displayed on my Windows box or my Linux boxen. -- Linux Home Automation Neil Cherry kd2zrq@... Main site My HA Blog Author of: Linux Smart Homes For Dummies KD2ZRQ
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Re: #qdx Unknown USB Device (Device Descriptor Request Failed)
#qdx
On 17/11/2022 13:12, Mitch Winkle wrote: Whatever happens at startup should happen on hot plug, I suspect. Mitch, It should. Hans has asked if anyone can help as he does not know why it behaves as it does in Windows. 73 Alan G4ZFQ
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Mouser,
Digikey,
Allied,
--
Allison
------------------
Post online only, please no email.
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On my second 50w amp can¡¯t find one?T250V NP0/C0G types with value 47pF, code ¡°470¡±. Cap¡it¡¯s small so there is a good chance it could have been pulled out with parts¡.if that¡¯s true then the carpet has eaten it¡..anybody with an idea where I can buy one stateside¡not going to bother Hans¡.guess I could ask for one when he sends my 17 qcx mini¡PayPal fees prob more than the part..
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Re: #gdx QDX Firmware Request: Phase Modulation (psk31, etc.)
#gdx
Many thanks for the comments Robin & Allison,
G3PLX assumes audio frequency generation of the phase shift.
By generating the FT8 type frequency shift directly at RF it seems that the QDX is able to remove harmonics by using the RF low pass filters, rather than an audio frequency low pass filter and the linear following stages of SSB generation.
This is a brilliant system, one reason I got a QDX, for the idea alone, not because I particularly wanted to FT8 on 40m? :-)
(still interesting to try it out though)
Currently the QDX does not have the software ability to create a direct RF phase shift modulation, so psk31 is not possible, as Allison says.
However the Si5351a can be programmed to create a phase shift directly at RF.
In this case, perhaps the harmonics might also be removed by the RF low-pass filters, in the same way as for FT8.
("amplitude management" was definitely not the right way of expressing myself !)
Yes, i came up with this request due to seeing the post about FLDIGI, not sure what Mitch is doing, but I joined that group anyway :-)
Regards,? Ed? G8BQR
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How does it behave on 12V?? Or can it?? I am not familiar with the circuit.
Thinking of a portable scenario where invariably power is 11V - 13.8V nominal.? Thus, if the amp performs at a lower output (on 12V) then all good.? The amp stays cooler and should be able to survive a higher duty cycle.
What are the issues with this thought process??
------- Original Message -------
On Wednesday, November 16th, 2022 at 11:12 PM, Joshua KJ7LVZ <joshuajayg@...> wrote:
Everything went fine. 40m is putting out about 45w and 20m is a little low at about 30w both at 20v. Bias doesn't change with band. Make successful tests on JS8 and packet tonight.?
Joshua
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Joshua KJ7LVZ
Ronald Taylor
Mitch Winkle