Re: Solder pot for toroid leads
Not needed. ?Spend the money on a decent iron then scrape and tin with a solder blob
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For ¡®hard as nails¡¯ motor wire either scrape completely with scalpel or burn off with a small blowtorch (also excellent for heatshrink)?
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Used to use solder pots 40 years ago (before blowtorch)?
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Re: 50 Watt Power Amplifier - Low Power, High Harmonics
#50w
#50wpa
Bill,
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I have attached a PDF of the K0IKR message with the scope traces.
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73
Evan
AC9TU
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Hi Hans,
I have just viewed you presentation you gave during the FDIM 2025
conference. Very nice. I feel sorry for you atan2 problem.
I have written a short note on complex filters for IQ signals, that
describes how to design filters without using Hilbert transforms
(reducing delays). It can also be used for SSB generation with a
reduced bandwidth in the polar method.
73
Anders, SM5KAE
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Hi Hans,
I have just viewed you presentation you gave during the FDIM 2025
conference. Very nice. I feel sorry for you atan2 problem.
I have written a short note on complex filters for IQ signals, that
describes how to design filters without using Hilbert transforms
(reducing delays). It can also be used for SSB generation with a
reduced bandwidth in the polar method.
73
Anders, SM5KAE
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QMX won't start after firmware update to 1_02_000
Just upgraded from pre-SSB version to 1_02_000 and now the QMX doesn't start again.
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- Only POP at headphones
- No display
- No serial port visible at computer
- With new upgrade all HW tests worked fine
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Battery voltage OK (not of course measurable from device).
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The device worked fine before this upgrade. What should I try to fix this?
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Re: Solder pot for toroid leads
Roy, the scrape and then add flux and solder works fine and is simple.
I had an old Radio Shack 110 v heated solder sucker that I removed the rubber bulb and plugged the sucker tip (so the whole end is hot) and drilled out the hole that the squeeze bulb had fastened to to make a solder pot. I saw the directions many years ago for this reuse of the old solder sucker. ?So I use that as a solder pot and it does help. ?I prop it in to position with a small vise. ?Hold the wire in the hot solder for a few seconds to a minute or two. Replace the solder often or just add liquid flux.
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On May 23, 2025, at 2:12?PM, Roy Ashkenaz via groups.io <cqk2rma@...> wrote:
? Does anyone use Solder pots for tinning and removing the enamel from the toroid leads? Any hints and tips?
I see a cheap one on Amazon for about $20. Any suggestions if I should buy special solder for this, or use my normal Kester 63/37 solder in it?
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Re: Solder pot for toroid leads
I typically use the entire skein of wire (as supplied in the QRP Labs' kits) to wind a toroid. Then I cut off the wire about 3 cm from the last winding of the toroid in question. That way I only use about 5 or 6 cm more than necessary for each toroid. Hans suggested lengths are very generous, so if you mess up a few turns on a toroid, you still have plenty. His wire skeins also are way more than enough to finish a kit. After a dozen or so QRP Labs' kits, I still have about half a dozen skeins of wire that I have available for more projects.?
If I need to use wire from a spool ? of wire, I first wind two turns on a toroid, mark beginning and end of the two turns, take off the turns and measure between the marks. Then I multiply half that measurement times the number of turns required for a toroid and add 8 cm. That gives a fairly accurate measurement for a particular toroid.?
I also keep the odd ends of wire. When you build a QMX, you have lots of different toroids. I use the odd lengths to wind as many of the toroids as I can. Keeps me from running out of wire in the middle of a build.?
--
73, Dan? NM3A
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Re: R520 Wrong component value.
Measure twice, solder in circuit once. ?Sorry guys and gals, I couldn¡¯t resist this early in the morning. ?I usually check each part before installing but lately have gotten a little lazy. Your comments have given me pause and I will be more fastidious in my building. ?When sorting parts for a kit I can see how all the colors can run together after a while.
Back to measuring and checking. I have all the tools and no excuse now.
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On May 23, 2025, at 11:44?PM, Donald S Brant Jr via groups.io <dsbrantjr@...> wrote:
? I had a 1% resistor sample kit whose resistors marked 10K were actually 1K.? I had some head scratching figuring out why the gains of my opamp circuits were all wrong.??
73, Don N2VGU
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Re: FDIM 2025 - Bringing SSB to the QMX (Hans's presentation)
I have held this question in until now. I don¡¯t even know the correct way to ask Google, but with all these different ¡°improved¡± methods of generating SSB can the average ham (let alone the 80 year old like me) tell the difference when listening on the air? ?Does it make a difference? Does the envelope hold open longer to increase power out or something like that. From what Hans has explained I get the feeling that some of the newer methods do increase the power out.
Thanks for any explanation or reference to a easily understood answer.
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On May 24, 2025, at 12:50?AM, Shirley Dulcey KE1L <mark@...> wrote:
? Did anyone out there notice that FlexRadio is now copying QRP Labs? Not really, but their latest product (the Aurora series, announced right around Hamvention and scheduled to ship in 4Q25) is using EER?(aka polar modulation) generation of SSB. They worked with K1KP, the developer of the Polar Explorer that was demonstrated in 2019, to integrate the technology into a transceiver.
Of course, Guido PE1NNZ and his uSDX beat both products to market. Hans explains it so well, I almost understand it.?
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Re: QMX+ firmware feature request
just a quick and quite possibly ill-considered thought ..
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.. would it be possible and useful to have a sidetone frequency shift as the SWR changes?? E.g. the lower the frequency the better the match?? Stepped tones perhaps.
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73
Rod
G0VKV
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Re: QMX+ and DTR/RTS like CW keyering
With the config CAT keying "Elecraft" its work fine. Many thanks Stan for your help.
Andre F6APU.
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Re: Missing Conductors - is it safe to apply power?
#qmx
Thank you Stan, that was very helpful and exactly what I was hoping for. I think I should be able to fit the Conductors in.
Unfortunately, after checking everything in the package again carefully I didn't find the capacitors in the knobs or other components.
But now I'm happy because I can at least finish the build to see if it will turn on.
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73, Dennis DM4NTZ?
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Hi guys,
I recently installed the new fw 1_02_00 on my QMX+. However, after listening on various frequencies I noticed that there are very strong and unwanted signals at the beginning of the band. In 20m it receives an S8 signal around 14,012.00 Khz and the same in 15 and 10m even without an antenna. I wanted to know if you also had the same problem. A friend of mine who uses the FW 1_01_003 beta let me know that with this version the problem exists but the unwanted signals are much more attenuated.
73 de IZ2BHP.
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QMX+ unwanted signals received
Hi guys,
I recently installed the new fw 1_02_00 on my QMX+. However, after listening on various frequencies I noticed that there are very strong and unwanted signals at the beginning of the band. In 20m it receives an S8 carrier signal around 14,012.00 Khz and the same in 15 and 10, even without an antenna. I wanted to know if you also had the same problem. A friend of mine who uses the beta FW 1_01_003 let me know that with this version the problem exists but the unwanted signals are much more attenuated.
Thanks for your reply.
73 de IZ2BHP.
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Re: QMX SWR measurement is not correct while using with PA
Yes, looks like it is not correct to use Nano VNA for impedance measurement for PA. Thank you! Is it possible to measure imaginary and real part of impedance for PA in some other way?
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Re: Release of version 2.0 of ABS solution for QMX+ (Automatic internal antenna tuner, internal battery and internal speaker with audio amp)
#PSU
#QMXplus
#audio
#ABS
#ATU
I am currently organizing a group buy for PCBs only:
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I want to build the kit and I am willing to order from jlcpcb.
Including: ATU board + Battery board + Front panel (tht) + rear panel (no sma)
You would have to order the missing through-hole parts on your own.
Price would depend on the amount of PCBs and shipping to your country.
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Roughly estimated: 48€ for PCBs + 15€ shipping in Europe.
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Please write me an email including your country if you want to participate: info AT dj1tg DOT de
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vy73 de
DJ1TG
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On Thu, May 22, 2025 at 04:54 AM, Roelof Bakker wrote:
In N1MM+ RUN mode and RIT on, the up or down key changes the frequency 10 Hz and no more, irrespective of the RIT tuning step setting.
The CAT monitor receives this: RD00010;? The LCD frequency read-out on the LCD changes from - 0.010 to +0.010 and vica versa.
It looks like the N1MM / QMX+ communication in RUN mode is restricted with RIT on.
This is because N1MM/Kenwood TS480 CAT implementation expects the RD00010; and RU00010; commands to be relative increments; on QMX they are implemented as absolute up/down offsets.
And note you can change the 00010 to a different value in the N1MM+ configurer; mine is set at 00020.
Furthermose, in RUN and RIT on, after using the up / down keys, RIT can not be switched off on the radio. Reverting in N1MM to S&P this works again.
I do not see this on my QMX+.? In either RUN or S/P, I can completely control RIT on the radio, and in RUN I have the minimal control discussed above.? And I can always turn RIT on/off with the control on QMX+ or the control on the bandmap in N1MM+, and adjust it using the radio's control.? I am running latest QMX firmware and latest N1MM+.
Stan KC7XE
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Re: FDIM 2025 - Bringing SSB to the QMX (Hans's presentation)
Did anyone out there notice that FlexRadio is now copying QRP Labs? Not really, but their latest product (the Aurora series, announced right around Hamvention and scheduled to ship in 4Q25) is using EER?(aka polar modulation) generation of SSB. They worked with K1KP, the developer of the Polar Explorer that was demonstrated in 2019, to integrate the technology into a transceiver.
Of course, Guido PE1NNZ and his uSDX beat both products to market.
Hans explains it so well, I almost understand it.?
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To be clear, I don't remember if the backlight actually did come on, as I didn't want to keep it connected to power any longer than I had to to check what the usb behaviour was (Up to that point the supply was set to act as a breaker as soon as an overcurrent event happened, vs supply limiting to a constant current which I did for the last tests). But the dark squares were very distinctive
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Hi Stan To #1, the DC plug isn't shorting, and the tab you mentioned isn't contacting the small transistor next to it To #2, resistance of PWR_ON and PWR_HOLD to all other pins in that connector: With PS #1 disconnected: PWR_ON to all >2Mohm, PWR_HOLD to all > 1Mohm, usually around 1.2M (I can get precise values to pairs if needed) With PS #1 connected: The readings in this section aren't super stable, I think the meter I've got at home is suspect. Values are what they seem to settle to, initial readings are much lower PWR_ON - PWM_5V : 50K PWR_ON - Vin : 95K PWR_ON - PWR_HOLD : 220K PWR_ON - ADC_5V : 120K PWR_ON - Vcc :? 130K PWR_ON - +12V : 150K PWR_ON - GND : 130K PWR_HOLD - PWM_5V : 200K PWR_HOLD - Vin : 310K PWR_HOLD - ADC_5V : 105K PWR_HOLD - Vcc : 100K PWR_HOLD - +12V : 120K PWR_HOLD - GND : 90K To #3, I've created a facsimile out of a picture from the operating manual, imagine the blue squares are the colour of pixels on the display  I won't be able to do any power on tests for the weekend, as I don't have access to a current limiting supply at home, and I'm absolutely not plugging this into a battery until I've figured out what's up. Thanks, Kait VA3KBY
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Bruce Akhurst
David Wilcox K8WPE
Shirley Dulcey KE1L