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Re: New Build but can¡¯t get firmware to load

 

Ludwig, what could be some reasons for overloading the 3V3 SMPS? I had to order a variable voltage supply so the power tests are on hold. Just trying to see if there¡¯s anything I can look at while I wait for Amazon.?
Wiki Notifications #wiki-notice

Group Notification
 

The wiki page QDX USB to serial for Win7 and Win8 has been created by @Ludwig_DH8WN <DH8WN@...>.

The wiki page QMX QMX plus USB to serial for Win7 and Win8 has been created by @Ludwig_DH8WN <DH8WN@...>.

Re: BS170 Heat flow experiment with results

 

Great work, thanks for sharing!?
?
I bet if you did just the flat of the transistor somehow, it'd be very close to the drain lead, but my guess is the case would still flow more heat than the drain lead.
?
Either way, this shows us that BOTH the case and the leads are significant. The gate lead is just under half that of the case as far as temp rise. In fact, combining all 3 leads... it appears you still have more heat coming from them (combined), I believe.?
?
-Nate
N8BTR
Re: New Build but can¡¯t get firmware to load

 

On Thu, Sep 12, 2024 at 08:56 AM, Alan G4ZFQ wrote:
Older computers? Windows 7 does not see my QDX.
Mike and Alan,
for older OS like Win7 please read QMX QMX plus USB to serial for Win7 and Win8
73 Ludwig
QMX+ receiver image on 20m

 

I was having a play in the CWT contest this morning on 20m, there were some extremely strong signals on the band.
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I noticed that there appeared to be weak images of the strongest signals approximately 22kHz higher up in the band which tuned in reverse to the actual frequency.
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Any ideas why this should be?? I seem to remember that an audio IF is used in the PCM1804 being mentioned.?
?
Steve G4EDG
Re: BS170 Heat flow experiment with results

 

That's not a lot of heat for each individual FET. The original QCX had them all standing up separately. I wonder if having them clamped down on a thin metal surface with an insulating PCB material underneath is a cause of heat accumulation.
--
73, Dan - W2DLC
Re: 50 watt amp bands

 

I have a 20m 50w amp in which I changed the LPF to 17m. With a 24v supply (modified laptop supply) I get 50w out on 20m and 35w out on 17m.
?
Sharing LPFs between adjacent bands is common on most HF rigs, including the QMX.?
?
Running this amp on 17m is probably at its upper limit.
?
73 Steve G4EDG
Re: IQ Mode image problem

 

Now sorted, sound affects on by default. win 11.
Re: Elephant in the room!

 

Thanks Marek
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I must have missed that! I'll look forward to the update in due course.
?
73 Steve G4EDG
Re: Elephant in the room!

 

Steve,
?
if I¡¯m not mistaken Hans mentioned band change by encoder turning in not distant future. At present other bugs and SSB is a priority. At least this is my understanding?
?
---------------------------------
73 de Marek SP9TKW
Elephant in the room!

 

Over the last few months there have been improvements made to the QMX+ firmware bringing enhanced functionality due to comments and suggestions made by group members...everybody has their own opinions of what should be a priority.
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The one thing that has never (or rarely) been mentioned is the truly inefficient and frustrating band change arrangement.
?
Of the four push button switches, the two associated with the encoders seem to be the most difficult to operate and get consistant? results from.?
?
To change bands requires a double press of the volume encoder to go up one band, there is no going down facility, thus to go down a band requires 22 button pushes! very wearing on the push button and operator. I find if the double press is not done exactly right it can result in powering down the rig or changing the mode.
?
As a work around I have filled the preset memory frequencies with the bands I'm interested in...i.e all but 60m and 6m, selection of band this way is a lot easier, but I find that these presets can easily be overwritten during selection, requiring a trip to the preset menu.
?
A few weeks ago a change was made to the "Tune SWR" operation, once in this menu item the band to test is displayed on the LCD and can be selected by the by the volume encoder, and the test started by pressing the menu button again...what a beautifully simple and efficient implementation of this function!
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My suggestion is to adopt a similar process to select the band.
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1. Double press of volume encoder
?
2. Select the band (as displayed on the LCD) using the volume encoder.
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3. Exit the function and set the band by pressing the volume encoder button again.
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Done!!
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The frequency for each band could be user set or a simple default value...just as long as it can't be accidently changed.
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I would suggest just one press of the volume encoder button would be better....i.e. one press for band change and two presses to change mode...but hey the front panel is etched with the info and cant be changed...though I could live with that!
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I can also see the volume encoder/LCD? being used with other menu options for easier operation i.e CW filter bandwidth selection...being able to tune the receiver while changing filter widths. Switching from the 500Hz filter to the 50Hz filter will inevitably result in losing the signal you are trying to optimise, to retune in the existing method requires going up and down the menu item (4 presses in each direction).?
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Just my ideas for a more ergonomic QMX+
?
73 Steve G4EDG
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?
?
?
?
Re: BS170 Heat flow experiment with results

 

Tony,?

That was a very well done experiment. Bravo!

It should do much to dispel the "all the heat leaves via the leads" myth that resurrects from time to time on this forum.

Thank you for that excellent work OM.

73 JZ KJ4A?


On Thu, Sep 12, 2024, 5:15?AM dl8lrz Reiner via <dl8lrz=[email protected]> wrote:
Very informative measurement by Tony.
The heat is therefore primarily dissipated via the FET housing and the drain wire, i.e. onto the board.
I don't have such convenient measuring technology.
A measurement on a closed QMX would also be interesting:
- a sensor between the FETs (FET temperature)
- a sensor on the board (board temperature)
- an air temperature sensor between the board/display
- a sensor on the lower housing shell
This would show where the heat dissipation should be improved (cooling hoods on the FETs or board to housing).
73 Reiner
?
?
Re: BS170 Heat flow experiment with results

 

Very informative measurement by Tony.
The heat is therefore primarily dissipated via the FET housing and the drain wire, i.e. onto the board.
I don't have such convenient measuring technology.
A measurement on a closed QMX would also be interesting:
- a sensor between the FETs (FET temperature)
- a sensor on the board (board temperature)
- an air temperature sensor between the board/display
- a sensor on the lower housing shell
This would show where the heat dissipation should be improved (cooling hoods on the FETs or board to housing).
73 Reiner
?
?
Re: New Build but can¡¯t get firmware to load

 

On 11/09/2024 22:07, Mike KK7MMN via groups.io wrote:
It¡¯s probably a simple setting and nothing else on my older computers, but I got lucky when it worked on hers!
I also hope someone has a correct answer instead of ¡®keep trying¡¯.
Mike,

I guess "Keep trying" is the right answer:-)
Older computers? Windows 7 does not see my QDX. Other seem to have OS problems.

73 Alan G4ZFQ
Re: 50 watt amp bands

 

I don't have to carry a transceiver QDX so I use an external regulated voltage source to power the output stage. For example, for the 80 meter band I supply about 4 Volts to the output stage.
--
73, Oleh, UY2ZA
Re: BS170 Heat flow experiment with results

 

Very nice experiment, Paul

Nice to see some real experimental data.?

I agree with Paul AI7JR, it would perhaps be interesting to measure with only the flat of the transistor face against the copper, since practically in a transceiver the curved part of the body is not touching the copper. I don't think there's any problem with the?measurements though; all the copper plates are the same size with the same dissipation to the environment so it's a reasonable relative comparison.

73 Hans G0UPL



On Thu, Sep 12, 2024 at 7:47?AM Paul - AI7JR via <paul.hanchett=[email protected]> wrote:

I wonder if it tells what we want to know...

"Wrap the BS170 case with copper tape and solder it to another copper plate."

In the QMX, only the flat side is connected to the heat sink... (Assuming the washer and screw aren't very significant!) If that were taken into account, heat extraction via the case and via the drain lead might be more comparable, maybe even swapped?


You're making the assumption that temperature at the measurement point is a proxy for power flow on the path. But the actual temperature is a function of the thermal resistance from the measurement point to the environment...


It seems to me that you'd need to standardize the thermal resistance of what you attach the measurement points to, in order to measure relative power flow.


This is giving me a headache! Am I making it harder than it has to be?


Paul -- AI7JR


On 9/11/24 20:42, Sandy via wrote:

Hey Tony - That is an interesting result. There is no substitute for actual measurement. This suggests that case contact with the pad is important. I always install the BS170s first with the screw and washer ensuring they are all flat and only then solder in place. Thanks for your efforts! Sandy KB3EOF


On 9/11/24 22:18, mux_folder2001 via wrote:
I have attached a PDF file that describes an experiment with the goal of determine where the heat flows in a BS170. The PDF contains pictures of the fixture and a graph of the results. The essence of it is that, given equal opportunity, heat will flow as follows:

  1. Best flow is through the case.
  2. Second best flow is the drain lead.
  3. A distant third is the source lead.
  4. Last is the gate lead.

The graph will give you a sense of how much difference there is between them.?

The transistor is configured in a DC circuit and is dissipating 767mw continuously in the test. I should have put that in the PDF file but I forgot to.

Tony
AD0VC
-- 
Paul -- AI7JR
Re: New Build but can¡¯t get firmware to load

 

I tried updating the firmware on two different older computers of mine and it never would show up as a drive¡­
then I connected it to my wife¡¯s newer computer and BAM.. it¡¯s a drive and I updated the firmware.
?
It¡¯s probably a simple setting and nothing else on my older computers, but I got lucky when it worked on hers!

I also hope someone has a correct answer instead of ¡®keep trying¡¯.
?
Re: BS170 Heat flow experiment with results

 

¿ªÔÆÌåÓý

I wonder if it tells what we want to know...

"Wrap the BS170 case with copper tape and solder it to another copper plate."

In the QMX, only the flat side is connected to the heat sink... (Assuming the washer and screw aren't very significant!) If that were taken into account, heat extraction via the case and via the drain lead might be more comparable, maybe even swapped?


You're making the assumption that temperature at the measurement point is a proxy for power flow on the path. But the actual temperature is a function of the thermal resistance from the measurement point to the environment...


It seems to me that you'd need to standardize the thermal resistance of what you attach the measurement points to, in order to measure relative power flow.


This is giving me a headache! Am I making it harder than it has to be?


Paul -- AI7JR


On 9/11/24 20:42, Sandy via groups.io wrote:

Hey Tony - That is an interesting result. There is no substitute for actual measurement. This suggests that case contact with the pad is important. I always install the BS170s first with the screw and washer ensuring they are all flat and only then solder in place. Thanks for your efforts! Sandy KB3EOF


On 9/11/24 22:18, mux_folder2001 via groups.io wrote:
I have attached a PDF file that describes an experiment with the goal of determine where the heat flows in a BS170. The PDF contains pictures of the fixture and a graph of the results. The essence of it is that, given equal opportunity, heat will flow as follows:

  1. Best flow is through the case.
  2. Second best flow is the drain lead.
  3. A distant third is the source lead.
  4. Last is the gate lead.

The graph will give you a sense of how much difference there is between them.?

The transistor is configured in a DC circuit and is dissipating 767mw continuously in the test. I should have put that in the PDF file but I forgot to.

Tony
AD0VC
-- 
Paul -- AI7JR
Re: BS170 Heat flow experiment with results

 

¿ªÔÆÌåÓý

Hey Tony - That is an interesting result. There is no substitute for actual measurement. This suggests that case contact with the pad is important. I always install the BS170s first with the screw and washer ensuring they are all flat and only then solder in place. Thanks for your efforts! Sandy KB3EOF


On 9/11/24 22:18, mux_folder2001 via groups.io wrote:

I have attached a PDF file that describes an experiment with the goal of determine where the heat flows in a BS170. The PDF contains pictures of the fixture and a graph of the results. The essence of it is that, given equal opportunity, heat will flow as follows:

  1. Best flow is through the case.
  2. Second best flow is the drain lead.
  3. A distant third is the source lead.
  4. Last is the gate lead.

The graph will give you a sense of how much difference there is between them.?

The transistor is configured in a DC circuit and is dissipating 767mw continuously in the test. I should have put that in the PDF file but I forgot to.

Tony
AD0VC
Re: #QMX Loaded FW 27, Now Dead? #qmx

 

Well that got me into the device, thanks.
?
I'm getting some weird data:
Voltage: 13.2v (input is still 11.4v)
5V SMPS: Status: Error
? ? ? ? ? ? ? ? ? Voltage: 4.6v (I was measuring 5.84v)
?
It seems satisfied with the 3.3v SMPS, although it's saying 3.57v where I was measuring 3.28v.
?
I don't have a way to quantify hot, but the microprocessor feels hot to me. Not burn yourself hot, but noticeable. I don't know how hot it's supposed to be.
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