On 08/11/2021 18:36, Suat Alper Seyhan wrote: Instead of connecting a 50ohm dummy if I try it again connected to good/resonant antenna may I expect to see different results? You will see different results but they will be wrong. You must use a dummy load, any signals or noise received will give false readings. 73 Alan G4ZFQ
|
Re: receiver module questions
Hi Peter,
since I am interested in the receiver module (keyword: WSPR-"Transceiver"), I would be curious to see what you can report in terms of sensitivity. I would be happy about your message here.
Karl-Heinz, DL6MEE
|
Interestingly the tone seems to be much louder relative to the band noise when using headphones over a speaker. Perhaps the impedance of the audio device you have plugged in is effecting this? The radio is almost unusable when using headphones, but with a speaker I can barely tell a tone is there.
|
I re-did the L12 quite carefully but pretty much nothing changed on the rf filter sweeps. Either I did the same mistake twice or there is something else going on. I was only looking to shape of the graph but when I now look in to numbers all the numbers are quite low compared to screenshots Hans shared. Instead of connecting a 50ohm dummy if I try it again connected to good/resonant antenna may I expect to see different results?
|
Re: On the TX signal, 5V tolerant I/Os and Pull-up resistors
Well that's good news I guess.... I thought you said that the TX line from the processor was not functioning at all... I guess I misunderstood.
As bad as it potentially sounds for Hans, in reality we are just helping him improve the product.? ?I am starting to think these issues are not "permanent damage" type of issues, so they can be worked through.
I am glad it at least works with a RPi for you, though.? That's not a horrible limitation by any means.?
Now that you mention this... maybe Windows vs Linux needs to be mentioned with these issues from now on...? ?
Fred W0FMS?
On Mon, Nov 8, 2021, 10:50 AM Evan Hand < elhandjr@...> wrote: All,
Just as a reminder the TX signal on my QDX is working fine.? The issue was the secondary check that the MPU does for a valid tone to set and not a failure of the I/O output.? For some reason, my Windows PC does not get along with the QDX.? My Raspberry Pi 4 seems to work.
Now if I can just keep from shorting out the finals again, I can find out why the output is low.
73
Evan
AC9TU
|
Re: New kit: QDX - QRP Labs Digital Transceiver
Regarding Olvia, I'm CQ'ing on 7.0714 dial (8/250), recorded it with another receiver, played the WAV in fldigi and it did decode! So I'll keep trying, see if I can make a QSO.
|
See the last page in the manual ( Page 106 in current version)? All of Hans' manuals contain detailed revision status.
|
Is it possible to get a summary of the revisions to the manual? I printed mine yesterday in anticipation of today¡¯s arrival and now see there¡¯s a revision posted today.?
Don
W6CZ
|
Re: On the TX signal, 5V tolerant I/Os and Pull-up resistors
All,
Just as a reminder the TX signal on my QDX is working fine.? The issue was the secondary check that the MPU does for a valid tone to set and not a failure of the I/O output.? For some reason, my Windows PC does not get along with the QDX.? My Raspberry Pi 4 seems to work.
Now if I can just keep from shorting out the finals again, I can find out why the output is low.
73
Evan
AC9TU
|
Bob,
Maybe try another PC if you have one.? As my posts in other threads have stated I am having issues with one of my Windows PC.? The Raspberry Pi seems to work fine.
The lack of current draw when in TX mode to me is an indication that the tone is not getting to the MPU.? Do you have the power setting in WSJT-X all the way up?? You cannot overdrive the audio, as it is only looking at the frequency.
73
Evan
AC9TU
|
Thanks Evan
?? I put the QDX in its case. The USB cable has ferrites on both ends. I also coiled the excess length and tied it together.
For these tests I'm transmitting into a dummy load and using 9 volts power, so I only have 2.4 watts out (T1 is 3:2).
? I still saw the same behavior. Flashing led with power output on 40 and flashing led but no RF out on 20, 30 and 80 with no current draw on those bands above receive.
? My low band antenna is a lazy (drunken?) sorta vertical 57' long that runs from the remote tuner at the corner of my garage to the top of a nearby tree. There is a buried radial field of wires out to the edges of the yard. Since I use a remote tuner there is close to 1:1 on the coax leading in, but I also have several turns of coax through 6 FT240-43 torroids. There's also a box with relays that switch in a loading coil for 160 m so the antenna can be tuned easily and it disconnects and grounds the antenna when power is off.
? Good luck with your low power problem.
--
? 73
??? KD8CGH
|
Re: Roots of Hans's supply chain issues
Love that movie!
Roy WA0YMH
Well, it?reminds me of my favourite "Snatch" movie line... "Never underestimate the predictability of stupidity".?
73 Hans G0UPL
On Mon, Nov 8, 2021 at 6:17 PM Mike Perry, WA4MP < editor@...> wrote:
> I don't think there's any great conspiracy or powerful forces directing it - but this is just the way the world system has been evolving. Thousands of individual decisions that make sense on a micro level, add up to make big consequences.
Quite right. I try not to ascribe to conspiracy anything that could be the result of stupidity. I once saw a cartoon that was all too apt. ¡°Be proud of your stupidity,¡± it said. ¡°It¡¯s what separates us from the animals."
For years I¡¯ve been warning Apple on Mac news sites not to do so much single sourcing, particularly in China. Always have several sources even if some cost more, I stressed. Recently, Apple announced that it would lose $8 billion dollars due to supply chain issues. I feel like I should bill them for business advice not taken.
And those California ports are jammed in part because the state¡¯s politicians stupidly passed a law that means that few trucks older than three years meet the pollution standards. Long-distance truckers, with more business than they can handle anyway, simply avoid trips into and out of the state. Politicians make one decision, thousands of truckers respond with another. No conspiracy. Just stupidity followed by a predictable and reasonable response. Truckers know trucking. Politicians do not.
¡ªMike Perry, WA4MP
|
Re: Roots of Hans's supply chain issues
There's something like the 'law of unintended consequences'. You do one thing that makes sense and all sorts of things happen that you didn't expect.?
--
73, Dan? NM3A
|
Brian, quick first question is what are you using for a power source? ¡°Wall wart¡± supplies are notorious for not always being well filtered and can cause such issues.?
Ron
On Mon, Nov 8, 2021 at 09:55 Brian Pease < bpease2@...> wrote: I just completed a new Progrock using the recommended power/regulator setup.? The voltages are correct, correct parts, no shorts on the boards, controller installed in the socket correctly. . It powered up with 4 flashes and output the default 10MHz on clk 0.?
The first problem is that the 10MHz signal is amplitude modulated with an audio frequency square wave of ~377Hz.? This is large, at least 50% modulation.
The second problem is that I cannot program a new frequency. Push-button presses of any short duration cause the LED to light only for the duration of the press. Repeated presses (5-10 or more) eventually result in the 4 flashes but programming is not possible.
Clock 1 has a rail-rail output of ~210kHz.
This is version 5. The controller is labeled pr1.02.
???????
|
I just completed a new Progrock using the recommended power/regulator setup.? The voltages are correct, correct parts, no shorts on the boards, controller installed in the socket correctly. . It powered up with 4 flashes and output the default 10MHz on clk 0.?
The first problem is that the 10MHz signal is amplitude modulated with an audio frequency square wave of ~377Hz.? This is large, at least 50% modulation.
The second problem is that I cannot program a new frequency. Push-button presses of any short duration cause the LED to light only for the duration of the press. Repeated presses (5-10 or more) eventually result in the 4 flashes but programming is not possible.
Clock 1 has a rail-rail output of ~210kHz.
This is version 5. The controller is labeled pr1.02.
???????
|
Re: On the TX signal, 5V tolerant I/Os and Pull-up resistors
Hi Fred?
I don't agree... When the pin is an output, the processor sets it at either 0V or 3.3V. Provided its current handling capability isn't abused, it doesn't matter what voltage it is "pulled up" to. It could be 1,000V provided the resistor was big enough, nobody would care.?
A 5V tolerant IO pin can withstand being connected to a low impedance 5V source. There are several clamping diodes in series so they don't draw huge current if the IO pin is connected to +5V.?
Those five pull up resistors are, categorically, totally unnecessary and totally harmless. Or I'll eat my hat.?
By all means remove them if it makes you feel better. I removed them in Rev 2. But not because they worried me at all. Just because less components is always better, even if only slightly so. More ground plane, less cost. Etc.?
I'm operating my QDX here every day without issues, on 40m and 20m. I've switched to 80m and 30m too but for receive only because my antenna isn't designed for 30m or 80m.
73 Hans G0UPL http://qrp-labs.com
-------- Original message -------- From: Fred Spinner <fred.spinner@...> Date: Mon, Nov 8, 2021, 7:27 PM To: [email protected]Subject: Re: [QRPLabs] On the TX signal, 5V tolerant I/Os and Pull-up resistors Interesting.? I am reading that you should not have those pull-ups to 5V there at all if the pin is used as an output.? The inputs have clamping diodes to clamp the 5v input to 3.3v.? If anything having a 5v pull up will burn off current for no gain in the STM32 through one of those clamping diodes.??
It probably makes sense to remove those pull-ups if for anything else lower current draw.? I would normally agree that the risk of damage doing this is low due to the 10k value of pull-up, but there is at least some circumstantial evidence that you might be seeing TX and LPF switching problems now from what is being reported here.? ?Could it be this?? I honestly think it could be.?
So yeah, I will probably pull them on mine.? Again, couldn't hurt, might help.?
Fred W0FMS Hi Fred
The 5V tolerant IO and the pull-up resistors to?+5V are all a red herring.?
According to the BS170 datasheet, the device has a gate threshold voltage of typically 2.1V but it could be as low as 0.8V or as high as 3.0V. I was nervous about?3.3V logic perhaps not driving it at sufficient voltage to be properly "ON". In other words not much safety margin between the 3.3V operating voltage of the microcontroller - bearing in mind the output will?not quite be rail-to-rail - and the worst case gate threshold?of the MOSFET.
My plan therefore was to use 10K pull-up resistors to?+5V. Then when I wanted the MOSFETs "On", I would set the I/O pin to be an input; and the 10K resistor would pull the MOSFET gate to?+5V. When I wanted the MOSFET to be "Off", I would set the I/O pin to be an output and set its level low. This is why you see these 10K pull-up resistors at the gates of the Tx/Rx switch Q6, and the three band select switches, and Q2 (on the TX signal).?
HOWEVER... I was mistaken. Because the transistor I used is BSS123 and according to its datasheet, its gate threshold voltage is minimum 0.8V, typical 1.7V, and maximum 2V. Therefore there is a lot more head room than I had expected with a BS170. So in the end, I did NOT keep to my original plan. I simply have the TX, RX and Band control signals all active all the time as Outputs, and set to high (3.3V) or low (0V) by the firmware. In either case (high or low), the pull-up to?+5V is of no consequence. It is an 0.5mA annoyance when the pin is at 0V, and a 0.17mA annoyance when the pin is at 3.3V. Nothing else.?
The microcontroller is not operated out of its spec. There is no possibility of damage. The pull-up resistors are ignored by the current firmware. Irrelevant. Unnecessary.?
As a matter of fact, in Rev 2 of the PCB, I simply deleted those pull-up resistors. I am talking about R5, R10, R11, R12 and R14. They are not required.?
Fred if you want to remove these resistors please go ahead. It makes no difference...?
73 hans G0UPL
|
Re: On the TX signal, 5V tolerant I/Os and Pull-up resistors
Interesting.? I am reading that you should not have those pull-ups to 5V there at all if the pin is used as an output.? The inputs have clamping diodes to clamp the 5v input to 3.3v.? If anything having a 5v pull up will burn off current for no gain in the STM32 through one of those clamping diodes.??
It probably makes sense to remove those pull-ups if for anything else lower current draw.? I would normally agree that the risk of damage doing this is low due to the 10k value of pull-up, but there is at least some circumstantial evidence that you might be seeing TX and LPF switching problems now from what is being reported here.? ?Could it be this?? I honestly think it could be.?
So yeah, I will probably pull them on mine.? Again, couldn't hurt, might help.?
Fred W0FMS
Hi Fred
The 5V tolerant IO and the pull-up resistors to?+5V are all a red herring.?
According to the BS170 datasheet, the device has a gate threshold voltage of typically 2.1V but it could be as low as 0.8V or as high as 3.0V. I was nervous about?3.3V logic perhaps not driving it at sufficient voltage to be properly "ON". In other words not much safety margin between the 3.3V operating voltage of the microcontroller - bearing in mind the output will?not quite be rail-to-rail - and the worst case gate threshold?of the MOSFET.
My plan therefore was to use 10K pull-up resistors to?+5V. Then when I wanted the MOSFETs "On", I would set the I/O pin to be an input; and the 10K resistor would pull the MOSFET gate to?+5V. When I wanted the MOSFET to be "Off", I would set the I/O pin to be an output and set its level low. This is why you see these 10K pull-up resistors at the gates of the Tx/Rx switch Q6, and the three band select switches, and Q2 (on the TX signal).?
HOWEVER... I was mistaken. Because the transistor I used is BSS123 and according to its datasheet, its gate threshold voltage is minimum 0.8V, typical 1.7V, and maximum 2V. Therefore there is a lot more head room than I had expected with a BS170. So in the end, I did NOT keep to my original plan. I simply have the TX, RX and Band control signals all active all the time as Outputs, and set to high (3.3V) or low (0V) by the firmware. In either case (high or low), the pull-up to?+5V is of no consequence. It is an 0.5mA annoyance when the pin is at 0V, and a 0.17mA annoyance when the pin is at 3.3V. Nothing else.?
The microcontroller is not operated out of its spec. There is no possibility of damage. The pull-up resistors are ignored by the current firmware. Irrelevant. Unnecessary.?
As a matter of fact, in Rev 2 of the PCB, I simply deleted those pull-up resistors. I am talking about R5, R10, R11, R12 and R14. They are not required.?
Fred if you want to remove these resistors please go ahead. It makes no difference...?
73 hans G0UPL
|
Re: QDX has no power out
#qdx
Hi Evan.
In my previous work life, I made use of the fact that most CPUs never go totally to 0.0 volts, they usually will be above zero and well under 0.5 volts. When I was trouble shooting a CPU or logic problem, if I measured true zero volts, I looked for a short. If I measured anything between zero and 0.5 volts, I looked for a logic problem. And if I still couldn't find the problem, I'd finally check the voltage at both ends of the PCB trace just in case it was open. It didn't happen often, but once in a while the pin would look soldered but would be floating above the matching pad insulated by a bit of flux. I can't begin to guess how many times there was a micro-thin short between pins or traces that I couldn't see even under the microscope, but washing away the flux residue and cutting between the traces would solve the problem. But I'd also say you are right to be careful before getting too frisky with the Exacto knife if you don't have good magnification to work with. :-) When I was doing repairs, I could always tell when the previous tech was using a 3x bench light instead of his 10x microscope while doing his soldering. The better the seeing, the better the work on small SMD parts. Good luck with the repairs.
Doug.
|
|
|
For those interested:
https://ae5x.blogspot.com/2021/11/spectrum-analysis-qdx-on-60m.html
--
John AE5X
|
Fred Spinner
N3MNT
Bob Benedict, KD8CGH
Ronald Taylor