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Re: Ultimate 3S overvoltage damage!

 

Good result John, glad the damage was limited to the MCU. ?You are correct that the power setting is only an indication inserted into the WSPR message. The only way to vary the power in the U3S is by adding extra BS170 transistors and increasing the voltage on the PA. ?It’s detailed in the manual. ?I run my PA on an 8V supply. 73 Nick G0OQK
Re: QMX and power bank PD

 

I've been using NiMH batteries for various rigs for some time now, and was planning to migrate to 18650 batteries. But my Iniu LiPo powerbank with 9V trigger cable was so inexpensive and convenient to use, I doubled down and bought a 2nd one (Safuel brand) on Black Friday.

72 de Russ, va3rr

On Mon, Dec 23, 2024 at 01:05 PM, Stan Dye wrote:

Don't hesitate to use this very
convenient solution.
Stan KC7XE
Re: USB-C to USB-C cable recommendation

 

A snap-on ferrite on either end of the USB cable will cut down on the RF getting into your laptop (and vice versa).
--
Steve KA0SM
Re: QMX+ with Macbook Air (Sonoma OS)

 

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Ron et el .......

I am up and running on my Macbook air thanks to Pierre.? This is going to be such a great help on my POTA excursions and other portable operating with the ability to control the radio and the logging.?

Ron, I don't think I am going to go through all the steps just to be able to run N1MM as there is sufficient IOS software to meet? my needs.? Thank you very much for your? suggestion and detail.


73's

Joe K8FC
Re: QMX+ Rev1 Not shutting down

 

Hi Stan,
?
MANY MANY THANKS.? Even though pin 7 visually had a good looking solder joint, when I tested continuity it was giving me some resistance instead of full continuity.? A touch up with the soldering iron and full continuity.? Plugged the QMX+ in, startup normal.? Upon shut down, Shut Down Msg appeared, then disappeared and YIPPEE, the LCD screen shut off, and pressing the on/off button the QMX+ started right up again.
?
Again, thanks for your clear directions and interpretation of a where the issue might be, and the fix.
?
Scott,
K1SMK
Re: QMX+ with Macbook Air (Sonoma OS)

 

Yes Ron that is what I select - TS480
I looked a little further and you can control the QMX from SkookumLogger. It's a bit tricky as there are sooo many shortcuts and having a MacBook Pro keyboard also adds to the fun (no Page Up / Down keys). I did manage to be able to shift either VFO A or B up and down in frequency and turn RIT on/off/up/down but still need to figure a few things out. Not sure the QMX has all the commands that are being sent to it or there are shortcut conflicts with macOS. It's a project!
?
Pierre
VE3HQZ
Re: QMX and power bank PD

 

I've patiently tried several.? Once negotiated the quality or not of? the? 9V? 15V etc is from the wall charger supply and as good as that is

Problems? ?The cable may output any available 'lower than requested' voltage if the wall charger socket negotiation fails or the wall charger socket doesn't do that particular nominal voltage.
e.g. I have a 20V trigger cable that gives 15V if plugged into one USB-C on my dual charger and 20V on the other (The Port PD capabilities vary) .?
Plug it into an old fashioned wall charger and out pops 5V

This can get confusing so do I end up tying the right cable to the right charger?? ?I'd rather buy a dedicated supply . .
Re: USB-C to USB-C cable recommendation

 

Belkin, Anker etc are usually good.? ? ? Name-letter-jumble amazon Ebay etc 50Gbps 500W bargains less so?
Re: RF output power on 160 and 80 meters

 

Thanks Curt and Enzo for the information.? I am using battery power to run the QMX + and the DC voltage is 11.8 volts. Sounds like I am good to go then.?
73,? Doug
?
?
Re: Ultimate 3S overvoltage damage!

 

All seems to be well with my Ultimate 3S now. I misunderstood about the dBm power setting in the menu, thinking I could control the power for there (although I couldn't see how). Now if I understand correctly, it's a way of inserting the (measured) power into the WSPR signal.
?
To help me visualize what's happening with the relays and filters I've soldered surface mount green LEDs and 1k resistors across the relay coils so now I have confirmation of which filter is in circuit. I've labelled the filter sockets with numbers 0 to 5 at one end and the band values at the other so I can put the filters back in the right places if ever they come out.
?
Thanks again to all who helped me with this.
?
73 and Happy Christmas,
?
John G4EDX
Re: Qmx+ 3D printed case

 

Its a speaker, not a fan ;-) I also have a small audio amp in there.
Re: Qmx+ 3D printed case

 

On Sun, Dec 22, 2024 at 10:18 PM, Larry Przyborowski wrote:

Will you share the stl files or sell them?

?

Tilting legs will be available in files section as soon as i get back to my pc in a day or two.?
?
I still need to do some finishing touches on model based on notes frome this proto and finish a speaker box to accompany the enclosure.
After that files will be available for small fee to anyone interested.
Re: QMX and power bank PD

 

I use exclusively a power-bank and simple PD trigger cable for my QMX and QMX+ power.? One is 12V, one is 9V.? They work flawlessly.? And the small Anker 10000mAh power banks I use are smaller than the QMX, and have enough juice for several hours of continuous operation.? Don't hesitate to use this very convenient solution.
Stan KC7XE
Re: QMX no Tx

 

Hi Paul,
1) turn back on your SWR protection to prevent damage if something happens.
2) your power supplies and bias current are fine
3) it should be pulling somewhere near 1A on transmit
4) although most of your filter scans look like a pretty good shape, looking at the left-hand scale, you see they are not getting activated properly: the scale should be going from about 0dB down to about -35dB.? Confirmation that your transmit is not working properly.
5) your SWR scans are irregular, further confirmation that something is wrong with tx.
?
First, make sure you haven't put your QMX keyer in Practice mode (a P will be in the display after the frequency).? That would cause all of the above symptoms, because transmit is disabled in firmware, and stays disabled even while running diagnostics.
?
Otherwise, this type of failure almost always means that one of the following assembly issues is happening:
1) One of the ends of L502 is not connected well.? This is not uncommon, especially if your kit used the larger gauge wire.? It must be scraped well at the ends to remove the insulation, since it will not burn off.? Even the smaller gauge wire, which has insulation that will burn off with solder does not always contact well if not heated well enough - even if the solder connection looks perfect.? I recommend removing and scraping the ends of the wire, and replacing (if you had the larger gauge wire), or if you used the same gauge as for the toroids, heat it again with a soldering iron set to at least 370C, and heat each connection for at least 10 full seconds.
2) One of the connections of T501 is not good.? You said you already re-wound this.? It is not typically the windings that are the problem if you have no tx, it is the connections.? Especially the center-tap connection with the twisted wires.? Even if the soldering looks perfect, the insulation can prevent proper contact.
3) One or more of the connections of T507 is not good.? Only the one single-wire 'turn' that connects the signal to the output could prevent transmit, but I suspect that is not your problem because you are receiving well.? However, if any one of the other connections is bad, it will prevent the SWR and power readback in the diagnostics from working properly.
?
Since your current draw is so low on transmit, I suspect it is one of the first two issues above.? There are several other things that can cause transmit to fail, including improperly installed BS170 transistors, and failures in some of the pre-installed surface-mount components, but these are very rare problems.? By far the above mentioned things are the most common failures.? Even if you are sure you soldered well.
?
I hope this helps, and you find the problem quickly,
Stan KC7XE
?
?
?
Re: Qmx+ 3D printed case

 

Ah, I see we're looking at two different efforts here. Both of you: amazing work. It's delightful to see all the creative work happening around the QMX/+.
Re: Qmx+ 3D printed case

 

That is super sharp! I especially like the fan and external access to the battery tray!
Re: QMX no Tx

 

Just a quick observation.

Your current limits look low.
Expect about 100 milliamps in Rx and close to 1A when Tx-ing.?

Maybe set your current limit to say ...? 1.25 A?

GREG KI4NVX?


On Mon, Dec 23, 2024 at 12:03 PM, Paul Bowen
<paulbowen@...> wrote:

Hi

I'm having problems with QMX version 4. It receives fine, with no issues,
but virtually no RF output. I can hear it in CW mode on another rig but it's
weak.
Using a current limiting PSU set at 11.5v .05 Amps RX .070 Amps TX.

In hardware tests mode the SWR jumps around even when the dummy load is
connected.
Using the Putty terminal emulator the SWR has very random values in every
band. Refreshing just comes up with a different set of values between 1 and
10.

I have rewound the Really Weird Twisted Sisters Transformer and turned off
the SWR protection. Checked the whole board with a microscope any
suggestions would be gratefully received.

Cheers

Paul
M0PNN
USB-C to USB-C cable recommendation

 

Would someone recommend a good well RFI shielded short (1-2 feet) USB-C cable?
Hiroki AH6CY
Re: QMX no Tx

 

Paul, is that a typo on your psu settings, or is that really only 70mA on TX? If so that definitely will give you low output. What current are you drawing as metered on your psu during TX? 73 Nick G0OQK
QMX no Tx

 

Hi

I'm having problems with QMX version 4. It receives fine, with no issues,
but virtually no RF output. I can hear it in CW mode on another rig but it's
weak.
Using a current limiting PSU set at 11.5v .05 Amps RX .070 Amps TX.

In hardware tests mode the SWR jumps around even when the dummy load is
connected.
Using the Putty terminal emulator the SWR has very random values in every
band. Refreshing just comes up with a different set of values between 1 and
10.

I have rewound the Really Weird Twisted Sisters Transformer and turned off
the SWR protection. Checked the whole board with a microscope any
suggestions would be gratefully received.

Cheers

Paul
M0PNN
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