Re: QRM from QLG3.

#125667

Hi Steve,
I don’t have a QMX, but I started with the QLG1 and my U3S tx, and the interference was to my HF rig, the FT897. Lots of ferrite experiments but the unscreened setup I never cured. Then I built the QLG2, same interference so I built it into a screened box, extensive experiments with connector filtering etc gave some improvement, I finally fitted an on/off switch so when on WSPR and all have stabilised, I could turn it off to stop the interference. This one even interfered at 2m. Then I built the QDX and used the QLG3 with the optional screen, used a short as poss connecting leads and ferrite blocks, but I still get some tramlines in FT8 and WSPR MODES if it is left on. I also built a standalone GPS enabled QRPLabs clock (QLG2 I think), but it blotted out my DAB radio when placed close by until I fitted ferrite clamps every couple of inches along the 5v wall mount PSU I use.
If I listen on 2m FM, at the same time as I use any of the kit above, I hears a background pulsing noise every second, so I assume this is the data burst. It is only at 9600 baud so I don’t know why it causes so much grief. If I run my FT896 Cat control at the same baud rate to my PC, I get no interference from that at all. It’s a mystery.
73 Ken g4apb?

Re: newby mistake,

#125666

开云体育

Bill,

I have had some criticism for drilling out the left over solder in a through hole opening but I have done it for years (not too many times though). I am just an old Osteopathic family doctor but have used a finger drill and the very fine bits with success. ?I was warned about drilling out the through hole plating but just added a little solder on both sides of the board. ?The few times I had to do that it did work…. So go drill! ?I would like to see what a “half” bit looks like…. Have had one root canal done but wasn't interested in the tools that day. Ha!

Be the REASON someone smiles today.

Dave K8WPE

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On Jul 9, 2024, at 10:39?AM, Bill VE3MRX <warubenstein@...> wrote:

?Thanks so much for all the advice, I am not the first one faced with this problem. ? A local ham with a big history of radio repair suggested drilling out the hole with a #60 drill bit. ?But as a retired oral surgeon, I still have a handpiece that is used for dental implants. ?It is very solid and has lots of torque. ?There is a dental burr called a half round. ?I dont remember what it is half of, but it is probably about 1/2 mm. ?I used it to drill out the holes and here is how it looked.

I salvaged 2 of the caps that I removed and replaced one with a duplicate I had in my junk box. ?I am hoping I did not screw up any of the layers of the board, but time will tell.

tnx agn all. de ve3mrx Bill 72
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Re: Monday 8 July: Hans Summers, G0UPL will be delivering a presentation on QMX+

#125665

The perfect quote after hearing the wonderful RSGB presentation by Hans:

"There is an influence which is getting strong and stronger day by day, which shows itself more and more in all departments of human activity, and influence most fruitful and beneficial—the influence of the artist. It was a happy day for the mass of humanity when the artist felt the desire of becoming a physician, an electrician, an engineer or mechanician or—whatnot—a mathematician or a financier; for it was he who wrought all these wonders and grandeur we are witnessing. It was he who abolished that small, pedantic, narrow-grooved school teaching which made of an aspiring student a galley-slave, and he who allowed freedom in the choice of subject of study according to one's pleasure and inclination, and so facilitated development."

- Nikola Tesla

-Steve K1RF

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------ Original Message ------

From "Hans Summers" <hans.summers@...>

To [email protected]

Date 7/9/2024 3:41:35 AM

Subject Re: [QRPLabs] Monday 8 July: Hans Summers, G0UPL will be delivering a presentation on QMX+

Thanks Chuck, Durk

FYI all: the video is on YouTube?

Chuck, the actual stats on assembled radios was 252 in March 2024, 210 in April 2024. May and June I didn't have time to count yet. But I expect May was a bit lower because so much effort was spent by the team on packing parts for 1,000 QMX and 1,000 QMX+ kits. Attached is my chart of the waiting list size since 1-Nov-2018. Yes, coming up to 6 years of having at least 1 employee here, doing assembly! You can see the list length is falling, as of last count (yesterday) it was 774. So that's around 3-4 months. We usually make some good progress in the summer months because there is some seasonal decline in order volume over the summer, freeing up some time; and also we can often find some?local uni students in need of some temporary summer holidays work.?

73 Hans G0UPL

On Tue, Jul 9, 2024 at 7:20?AM Chuck AI7SY via <chuck=[email protected]> wrote:
The talk was interesting, though mostly stuff you might have read already from bits of the web site. Two things new came up. Hans has 12 people working at kitting and building assembled units, and they're doing about 200 of the latter per month.

The other was updates. Two were mentioned specifically:

1) SSB and multitone digital modes (weeks or months, NOT 2025)
2) a scripting language (BASIC at this time) for user customization

That is all.

Re: QRM from QLG3.

#125664

Ian, Ken and Dave

Thanks for your comments confirming I'm not imagining hearing things!

Ive looked at the data line on the QLG3 and I see a short burst of data every second, but cant imagine that this is the source of what I'm hearing i.e. long periods of what appears to be a pure sine wave around 700Hz, I can also hear a similar pattern but much higher in frequency, 5000Hz maybe, in the background.

The fact that these signals cant be tuned by the VFO suggests to me that the signal is not being processed in the same way as receiving a signal off air, it seems like it is getting into a stage much later.

In Hans' recent YouTube video, he says that the receiver is not strictly a direct conversion as in the QCX, but has an IF of 12kHz implemented in the audio chain, achieved in the magic of the firmware. I wonder if the interfering signal is getting into the system at this stage.

I wonder if the QLG3 is generating signals internally in the range 0-48kHz which are getting into the audio system at the 12kHz IF frequency? I dont have a spectrum analyser, but would be interesting to see.

Ken, I wonder if you have only experienced this on the QMX/QMX+ ? you mentioned that you have experienced this? problem with the QLG1 and QLG2, both of which preceded the QMX.

Perhaps this is just a minor annoyance at the moment, but can see it becoming a significant problem as the firmware is developed.

Maybe the best solution is a toggle switch on the back panel to remove power from the QLG3 until its needed!?

73 Steve G4EDG

Re: newby mistake,

#125663

I recommend a desoldering gun with built-in vacuum pump, adjustable temperature control, and replaceable tips of various diameters, such as the Hakko FR-301.? Several other manufacturers offer similar products.? I have a hand tremor that makes it very difficult to hold a soldering iron, especially when components are spaced close together.?? I had just about given up assembling kits because I spent so much time fixing my own mistakes.? Then a friend told me about his Hakko and I found out that once a year the factory has a 50% off sale, and it just happened to be the next day.? I figured I could try it, and if it didn't work out, I should be able to recoup most of my money on eBay, so I bought one.? It's so nice that I kept it.? Highly recommend it!

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On Tue, Jul 9, 2024, 11:26 Donald S Brant Jr via <dsbrantjr=[email protected]> wrote:

On Tue, Jul 9, 2024 at 11:03 AM, Eike Lantzsch wrote:

The low-tech toothpick method is far safer.
A suitably-sized sewing needle works well also and will not damage the board.?
The via "barrels" which connect the board layers are very thin and fragile electroplated copper so I keep drills and abrasives away from them.
One tactic to deal with a hole which has had most of the solder removed but there is a stubborn residue, is to add MORE solder to fill the hole, and start over.
73, Don N2VGU

RSGB Tonight at 8 video - going for record?

#125662

Hi all

1.8K views for my QMX+ talk? after not much more than 1 day! Apparently the record to beat (for Tonight at 8 series), is 4.5k... I'm going for the record!

73 Hans G0UPL

Re: Another QMX+ got onto the air

#125661

Nice build, Lex!?

Lots of details?and great tips. I chuckled at the mindful toroid winding! I have added a link to your build process at the bottom of the QMX+ page along with a link to the RSGB video on QMX+, and Hannes DL9SCO's video on QMX+ construction.?

73 Hans G0UPL

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On Wed, Jul 10, 2024 at 1:17?AM Lex PH2LB via <lex=[email protected]> wrote:

Hello all,

Today I finished my QMX+ and after some initial configuration / diagnostics I measured the output power by triggering in TX in the diagnostic screen.?
The power outputs where (for 9V):

160m - 5.75 W
80m - 5.00 W
60m - 4.47 ?W
40m - 4.47 W
30m - 4.57 W
20m - 3.09 W
17m - 2.57 W
15m - 2.88 W
12m - 2.14 W
11m - 3.24 W
10m - 2.95 W
6m - 2.09 W

As expected there is a roll off at the higher bands and as observed before by other builders a dip on the 17m band (compared to 20 and 15m).

The diagnostics showed nice curves on the LPF and audio filters. But the RF filters look a bit funky (not like the manual, so there is some work to be done there.?
But as this is for the RX part, I fired up WSjtX, monitored the 40 and 20m band for a while and? made a few FT8 QSO's on those bands for testing.?

Next steps will be taking a closer look at the RF filters, do some more RX with it, take a better look at all the configuration options (big thumbs up for the terminal interface for easy configuration).??

The build, which took me a few weeks instead of a few evenings to complete due to personal reasons,? I documented in a kind of blog style on my website: (still needs some text to be added and edited). Growing into be a grumpy old man,? I don't mind SMD, but? find it sad that there are less through hole components to be installed compared to the QCX+ ;-) ??

Hans, again you showed me that you make great hamradio kits which are a fun to build. I tip my hat for you.?
--

73 Lex PH2LB?

Re: FT8 waveform

#125660

Hello Gabriel

You can read the assembly manual for the QDX which has a theoretical?description section, the description of the audio frequency measurement etc during FT8 transmission is described in detail and is the same in QMX.?

> I'm curious if this technique also honors the FT8 Gaussian smoothed waveform.

Yes, it does. In the default settings, the frequency is updated 100x per second. There is an illustration of the frequency shift in the QDX manual. You can actually increase the update rate which would decrease the step size. Even a single cycle measurement (no averaging) has a very high accuracy of around 0.05Hz at 1500Hz (for example). So one could exchange frequency precision for smaller step size as the frequency tracks the frequency shifts. Either way, the steps are already small and the frequency precision is extremely high, and I doubt?that fiddling around with this adjustment would make any measurable difference to communications?effectiveness.?

Note that the FT8 article shows two consecutive tones of FT8, having a Gaussian amplitude shaping, such that as the RF envelope amplitude of the finishing tone is ramped down according to the Gaussian profile, the RF envelope of the next tone is simultaneously?increased according to its Gaussian leading edge profile. The QEX article shows in a diagram, the superposition of two consecutive independent tones, having Guassian trailing and leading edge profiles respectively. This is also mathematically equivalent to keeping a single carrier amplitude constant, and sliding its frequency gently along a Guassian profile from the finishing tone to the next tone frequency. This is why QDX works with this "slide" method.?

73 Hans G0UPL

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On Wed, Jul 10, 2024 at 7:43?AM Gabriel LW2DVL via <gabriel.velo=[email protected]> wrote:

Hello everyone,

I ordered my first QMX a couple of months ago and, in the meantime, I've been investigating some features of this amazing? transceiver. I read in a post that the QMX synthesizes the output signal by estimating the frequency of the input audio from the PC. I'm curious if this technique also honors the FT8 Gaussian smoothed waveform. Is there any documentation about how the output frequency is synthesized?

73,
Gabriel
LW2DVL

Re: QMX Carry Case

#125659

I’m a big fan of those hard shell zipper cases. ?I’m practically addicted to them. ?I must have more than a dozen now, I put everything in them. ?I’ll keep these suggestions in mind when I order my QMX?

FT8 waveform

#125658

Hello everyone,

I ordered my first QMX a couple of months ago and, in the meantime, I've been investigating some features of this amazing? transceiver. I read in a post that the QMX synthesizes the output signal by estimating the frequency of the input audio from the PC. I'm curious if this technique also honors the FT8 Gaussian smoothed waveform. Is there any documentation about how the output frequency is synthesized?

73,
Gabriel
LW2DVL

Issues with summer travel and hot cars?

#125657

Hi everyone, I hope this isn’t too strange of a question but I’m curious what Folks can tell me about concerns with summer travel and leaving radios in a hot car. I’m planning a trip into Utah this month and thought about bringing a couple Elecraft radios but changed that now to my QCX mini. Should I be concerned with leaving it in a hot car in a southern Utah summer or am I being overprotective of one of my favorite radios? ?I’m guessing it’s a non-issue as lots of mobile radios stay in hot cars their entire life, but just wanted to hear whatever everyone else has to say about this.

Thanks.

Nolan

Re: QMX Carry Case

#125656

On Tue, Jul 9, 2024 at 08:47 PM, Rob VK5ZIK wrote:

Unfortunately Amazon doesn't ship that case to VK - obviously it is a dangerous item...Hi Hi

I think that they make that determination on a (cough) case-to-case basis.??
73, Don N2VGU

Re: QMX Carry Case

#125655

Ooh!  That's on sale on Amazon.ca for 10.5 canuck bucks!

72 de Russ, va3rr

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On Tue, Jul  9, 2024 at 01:36 PM, Robb Bates wrote:

I use this case.

Re: QMX Carry Case

#125654

G'Day Robb (again)
I do like your case, there seems to be enough depth for the encoder knobs.
Unfortunately Amazon doesn't ship that case to VK - obviously it is a dangerous item...Hi Hi

Rob
VK5ZIK

Re: QMX Carry Case

#125653

G'Day Robb - I have both the Hi & Low Band QMX. So I have a larger case that holds the antenna, cables, battery, etc
I am after an "individual" case to protect the radios individually.
Rob
VK5ZIK

Re: QMX for 40, 30, 20, 17, 15, 12, & 10 Meters?

#125652

Hey this is my project :)

For QDX and QMX (I done this before by the help of Ross, now it is more clear with QMX+)

I am using QMX+'s LPFs and BPFs on those bands

Only problem I had was

I need more columns on band configuration on QDX to make things clearer.

On QMX no problem with the new firmware

let me share what I shared to Hans here

-----------

For some reason on QDX
If you include the 30m frequencies to the 40m band 30m doesn't work
so 40m and 30m are defined separately.
now 17m frequency is defined inside 20m, 17m deesn't work
most probable 11m frequencies doesn't work inside 10 m band

For the very future development:
Please put 8 colums on Band Configuration for QDX.
40 30 20 17 15 12 11 10
00 00 01 01 01 02 02 02 LPF
00 00 01 01 02 02 03 03 BPF (this is very smart)

-------------

IMPORTANT: on QMX BPF numbers go? 3 2 1 0, reverse of QDX and QMX+

And I used 2 toroids on BPFs like the 60-15m QMX (I used the calculations from the QMX+)

73 DE muhsin TA1MHS