(tr)uSDX Forum

Thank you. I guess that I'll announce new restrictions to my group.

73, Bill

Three questions from Robert WA2T directed to Guido, and merged at Robert's request - VK4JJ

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1. Looking at two units, they both seem to TX high in frequency in FM mode. About 4.54 kHz on the one and 4.64 kHz on the other. Is this expected? I am not overly concerned as I am not sure FM mode would be useful on the bands the (tr)uSDX covers, but thought Guido might like the feedback.

BTW, this was after matching CW QRG on both rigs by adjusting menu item 8.3 Ref Freq to my IC-7610 receiving.



2. Noticed just now that if Tune Rate is changed (to say 10 Hz for CW) and then band is changed, Tune Rate returns to default (1 kHz).

Checked two units, one with 2.00f firmware and the other 2.00g (which is beta), both the same in this regard.


3. I am getting toward the testing phase of my builds and found that the PTT on Tip and MIC on Ring is reversed from how many/most mic plugs are wired. To work around this, I made a patch cable (3.5mm M to 3.5mm F) to reverse the connections externally.

I thought about looking into reversing the two jack pins on the PCB, but from what little looking I did it seems that the traces needed to be swapped may be on the inner layers of the PCB. But, if that were to be done, then the Keyer Paddle pins would also get reversed (and they match typical paddle pinout).

So, my question is if there is a reason this jack pinout scheme was chosen for MIC and would it be worthwhile to consider changing? I assume this would be possible with a firmware change? Perhaps it is not that simple.


73,

Robert, WA2T

storyofyouandme wrote: ↑17 Jan 2022, 17:10 Hello, Robert, wa2t, thank you very much for your reply. If you can, can you share the finished pictures of the motherboard and RF board? I want to know the direction of all the chips and those components are empty. thank you.
73.

The iBOM provides exactly what you are looking for, suggest checking it (them) out!

73,

Robert, WA2T

From the thread "Unnormal Power", quoting myself:

I have one unit (of five) where the power is way off as well (~11W when it is really about 5W). SWR on this one is off as well, reading 9.99. Everything looks normal on the board, I have not tried putting my fingers on the capacitors, I will and see if I find the same thing you did.

73,

Robert, WA2T
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wa2t

Posts: 77
Joined: 01 Jan 2022, 11:30
Contact: Contact wa2t

Re: Unnormal PWR

Post by wa2t » 15 Mar 2022, 08:32
The magic finger does mitigate the issue on my unit(s) as well. There is indeed a problem with what is presented to these ATMEGA inputs.

From a web search: "The ATmega328P datasheet has this info way in the back: Table 28-16 (page 328). The analog input resistance is claimed to be 100 Mohms. During an actual sample, the input resistance is temporarily a lot lower as the sampling capacitor is charged up so it is recommended that whatever you connect to the A/D have an output impedance of 10k or less for best accuracy."

What I have arrived at (in not a particularly scientific manner) is remove C7 and C8, replace them with 1M resistors and change R5 and R6 to 1K. Getting steady readings and pretty good correlation with LP-100A used as a standard for PWR and SWR measurements.

73,

Robert, WA2T

PWR/SWR does not display when either of CW Keyer modes is enabled, only when in CW Straight Key mode, is this intentional? I would think PWR and SWR should be shown in all possible modes unless there is a technical/firmware limitation. I did not check the voice modes for this issue, I will do that.

73,

Robert, WA2T

wa2t wrote: ↑15 Mar 2022, 12:37
What I have arrived at (in not a particularly scientific manner) is remove C7 and C8, replace them with 1M resistors and change R5 and R6 to 1K. Getting steady readings and pretty good correlation with LP-100A used as a standard for PWR and SWR measurements.

(tr)uSDX PWR and SWR readings are now stable and fairly close to LP-100A. SWR is within .1, PWR reads anywhere from 0.1 to 0.3W low, is there a "calibration factor" for PWR in firmware that perhaps could be adjusted?

73,

Robert, WA2T

Another operational observation: If CW paddle plug is removed while in CW mode and Iambic key mode is selected, endless string of Dah's ensues. Only way to stop it is power cycle the rig. If mode is first changed to USB (for example) and then the key plug is removed, no problem.

I have installed the Beta firmware R2.00g.
What does " R Shunt " do ?

Philip G7JUR

Hello everyone!
My (tr)uSDX of Chinese origin arrived with the firmware already installed. This means I didn't see the serial number of my rig. Is there any way to have the serial number displayed now? Or do I have to go through the whole bootloader upload process again to get the serial number?

73 de Matej OK2MTB

@Matěj OK2MTB if you do not know the serial number, you can first download the latest firmware over USB with zeros as S/N, uploading it will show you the S/N subsequently that you can use for the download. There is some unfinished WIP to show the S/N in the menu which can be used in the near future.

@Philip G7JUR, R Shunt is the resistance of the PCB track on the RF board that feeds the drain inductor of the PA. It is used to measure current/efficiency of the PA, and should have a resistance of about 17mOhms. In order to calibrate the efficiency measurement we have build-in this feature to correct potential mismatches that can occur on some PCBs, we have seen a resistance of 23mOhms instead, which would lead to a low-efficiency indication where in reality the efficiency would be much higher.

@Robert, WA2T Thanks for your feedback. We are aware of the issue and working on a a potential solution. Thanks for reporting the other bugs as well.

Thank you Guido.
Another question: My chinese (tr)uSDX with the receiver not working correctly (description of the problem is here) sometimes shows "25" instead of the S-meter value. Does this number have any meaning and can I deduce anything from it?

pe1nnz wrote: ↑16 Mar 2022, 18:04 @Matěj OK2MTB if you do not know the serial number, you can first download the latest firmware over USB with zeros as S/N, uploading it will show you the S/N subsequently that you can use for the download. There is some unfinished WIP to show the S/N in the menu which can be used in the near future.

@Philip G7JUR, R Shunt is the resistance of the PCB track on the RF board that feeds the drain inductor of the PA. It is used to measure current/efficiency of the PA, and should have a resistance of about 17mOhms. In order to calibrate the efficiency measurement we have build-in this feature to correct potential mismatches that can occur on some PCBs, we have seen a resistance of 23mOhms instead, which would lead to a low-efficiency indication where in reality the efficiency would be much higher.

@Robert, WA2T Thanks for your feedback. We are aware of the issue and working on a a potential solution. Thanks for reporting the other bugs as well.

Thanks for the info.
Philip

HI Manuel / Guido,

I am continuing to enjoy my rig and have just improved the audio significantly by replacing the U9 op-amp with the specified device (we were using LM833 due to availability.)

However, my request is in relation to CW. Although the specced op-amp has improved the audio significantly and reduced artefacts, I wonder if there is more that can be done with the CW filters in software? They don't seem to cut off properly, and even with the 200Hz filter enabled, it is still possible to discern the same single CW transmission across almost 1.5kHz of band. This can make operating on a busy night or at the weekend very difficult. Also I wonder if some sort of zero-beat indication can be built in?

Keep up the good work and I am pleased to se you now have a few official kit distributors.

Best 73,

Daimon. G4USI

For 20 meters on the RF board, with 3 BS170's, using the Lo Band-slot assignment, should the total capacitance for C10+C11 = 128 pf or 68 pf ?
Which is correct?
Thanks

Ohwenzelph wrote: ↑27 Mar 2022, 21:44 For 20 meters on the RF board, with 3 BS170's, using the Lo Band-slot assignment, should the total capacitance for C10+C11 = 128 pf or 68 pf ?
Which is correct?
Thanks

68 pf per the BOM and schematic.

Hi guys.

I have one of these kits and am also considering becoming an authorized distributor getting the boards printed here in Japan possibly.

First step before we can transmit on a kit transciever in Japan it has to pass a design principles review. This is not difficult, but costs around 40 dollars for the first kit and 10 for each additional kit by a specific amateur.

To apply for the review we need to submit the schematic and an rf block diagram like the one pictured here: https://blog.goo.ne.jp/boompunch/e/0b10 ... 95cb5450cc

I am wondering if you guys already have something similar from the design process that I could adapt for use in Japan? I just wanted to check before I start reinventing the wheel here.

If we can get it to pass the standards review then I believe this would be a very popular kit here in Japan, but currently it is virtually unknown because of the initial work required to meet the legal requirements for transceivers in Japan. We may also have to disable transmit on 60m in the firmware as that band is not permitted here.

Cheers and thanks for any help in advance.

De/ JJ1ILX. David

For the (tr)uSDX, I have not seen a block diagram. Schematics are, of course, downloadable from the dl2man.de main site.

For the predecessor of the (tr)uSDX, a block diagram can be found at https://github.com/threeme3/usdx
You could rework this for the (tr)uSDX.

As for the band disablement, this is unlikely to be supported by the devs as a standalone feature. Suggest you only produce the classic/high-band alternative RF board (and that would help the project if you can calculate real-world values for the inductors/capacitors too!).

JJ1ILX wrote: ↑05 Apr 2022, 22:41 Hi guys.

I have one of these kits and am also considering becoming an authorized distributor getting the boards printed here in Japan possibly.

First step before we can transmit on a kit transciever in Japan it has to pass a design principles review. This is not difficult, but costs around 40 dollars for the first kit and 10 for each additional kit by a specific amateur.

To apply for the review we need to submit the schematic and an rf block diagram like the one pictured here: https://blog.goo.ne.jp/boompunch/e/0b10 ... 95cb5450cc

I am wondering if you guys already have something similar from the design process that I could adapt for use in Japan? I just wanted to check before I start reinventing the wheel here.

If we can get it to pass the standards review then I believe this would be a very popular kit here in Japan, but currently it is virtually unknown because of the initial work required to meet the legal requirements for transceivers in Japan. We may also have to disable transmit on 60m in the firmware as that band is not permitted here.

Cheers and thanks for any help in advance.

De/ JJ1ILX. David

Hi David,

could you please find out the specific requirents to be fulfilled, and provide us with some links, so we can look it up ? e.G. Which frequency should be limited etc.
Also another interesting question would be:
If you can easily bypass the restrictions by installing another firmware, or just doing a menu selection, will this be allowed ? Because I don´t think we could make it "safe" in terms of "you cannot undo that" within reasonable amount of effort.

73 Manuel; DL2MAN

Hi Manuel,

I will work on getting the details together to share. I do not believe it is super complicated . People have even managed to get Baofengs registered here though the registration fee is more than the transciever. With my FT-991a it is the same radio physically as sold in the states, and they have different versions with power and band restrictions based on license level, but the firmware can be changed if license is upgraded or if you move to another country.

So I imagine just disabling the restricted frequencies in firmware is acceptable as that is how all the commercial rigs are doing it.

I will dig around and find a registration package for another kit with simIlar functionality. I did verify the harmonic supression is better than the minimum required under the new spurious emission requirements that just went in effect.

@Guido, PE1NZZ

Hi Guido,

I know the FW is closed source, which is fine for me, but..

...is there
- Roadmap of planned future improvements/fixes
- a change log of the FW
which lists the actual and Beta FW and somewhere available?


Just want to see when and which fixes are implemtented, to judge if I update or not...

The feature I am hoping for is a soft-audio interface based on the USB connection, it was mentioned in one of the threads, but I wonder if it could be realized with existing computing power and available RAM in the current (tr)uSDX

73 de
Alex, DK4FT

It would be great if while in CW mode the PTT button always operated as a straight key even if the Keyer parameter is Iambic x.

W6LKB wrote: ↑12 Apr 2022, 17:24 It would be great if while in CW mode the PTT button always operated as a straight key even if the Keyer parameter is Iambic x.

This unfortunately is impossible, as PTT and DIT are in parallel and share the same uC Input.
But check out the new Beta Firmware....
When in Keyer Mode, you Press PTT or DIT for a Series of Dit´s it will go into continuous Key Down for Tuning/SWR. If you´re a thumb dah guy, like me and you swap DIT and DAH in Menu, it will be a series of DAH´s that trigger Tuning mode.

73 Manuel; DL2MAN

Hi Manuel / Guido,

I just wondered if you might be able to answer my post of the 4th January in this thread please?

It concerns CW filtering.

Thanks - I appreciate you are busy people.

Daimon. G4USI

BrendonHills wrote: ↑13 Apr 2022, 14:34 Hi Manuel / Guido,

I just wondered if you might be able to answer my post of the 4th January in this thread please?

It concerns CW filtering.

Thanks - I appreciate you are busy people.

Daimon. G4USI

Your Post from 4th January in this thread covers Band Setup.
It has been answered here (on the same day):
viewtopic.php?p=300#p300
and most recent development is this:
viewtopic.php?t=217

If there was another question, I did not see, please post a link to the message or ask again.

73 Manuel; DL2MAN

DL2MAN wrote: ↑13 Apr 2022, 20:07

BrendonHills wrote: ↑13 Apr 2022, 14:34 Hi Manuel / Guido,

I just wondered if you might be able to answer my post of the 4th January in this thread please?

It concerns CW filtering.

Thanks - I appreciate you are busy people.

Daimon. G4USI

Your Post from 4th January in this thread covers Band Setup.
It has been answered here (on the same day):
viewtopic.php?p=300#p300
and most recent development is this:
viewtopic.php?t=217

If there was another question, I did not see, please post a link to the message or ask again.

73 Manuel; DL2MAN

My apologies! I joined the Forum on the 4th Jan! The post I was referring to is dated 23rd March.

Thanks very much.

Daimon G4USI