Back at it again.? Three different USB cables, which work with other devices with two different computers.? Still no go,? This is the only item purchased from QRP Labs that I have had an issue with.? All the other items are fantastic.

Is it still an error on my part or a typical Windows issue?? Not sure..??
a short note...? ? Please do not send me a personal email via my call sign stating,? read the directions that Hans has written / I have three of them working.? I am not foolish and that sort of non-help is a waste of my time.

Thank you

If you install the navigation software you can select which of the available systems it uses but I think it’s only L1 (as are 99% of the cheap GPS antennas )?

开云体育

My few cents:?
I have absolute volume and side tone set at 48. If I do not crank up the volume (when receiving strong and medium signals) then the clicks are not an issue. In case of faint signals (very often now that I try to do a lot of DX contacts in 10m) then as I turn up the volume, then the clicks become an issue. By the way, I use in ear headphones.

Hope this helps!

Joan

Just adding my experiences to the thread. This is what the sidetone on mine sounds like. Sidetone relative, but I found no settings I tried made much difference. This is 20M into a dummy load.?

Brian
n1bs

Just to clarify, I meant the same as one another, not the same as yours.

73, Mike KK7ER

Thanks, Hans (and others who wrote)... I don't need a priority - I'll wait my turn... just didn't know when I might expect it... Now I understand the back-log!
Have a great day!
73
Larry
AH6AX

Hi Hans,

Wondering what your thoughts are on this now we have colected quite a few responses? It seems overwhelmingly like this is a real problem preventing many of us not using the QMX, or having to "work-arounds" to minimise the issue.

Thanks

Daimon. G4USI

I posted this fix a couple months ago.? Without the relief cut, the boards flex when the case halves are assembled.? I assume most don't experience this binding.

--

73, N4TVC, Randy

Noting there has been very few responses advising that clicks are not evident (I counted one - with AGC off), perhaps the thread title is not helping as anyone who reads it, may skip over it thinking "I don't need to worry about that".? Perhaps a new thread (title) is needed.

73


Simon
VK3ELH

As an aside, maybe a bug, maybe something for a future revision (Probably hard to fix), I found a minor mechanical interference that you probably already know of.? It's between the mounting screw of the power supply board and the enclosure.? It's very minor, and you can just kind of force the two together and it still works.? But it was bothering me that the two halves didn't quite fit together right and smooth, so I kissed the inside edge of the case with a 3/16 end mill bit in my mill and took a small chunk out of the case.? Picture below.? With this taken out, the nylon screw and the case no longer interfere and the case goes together just right.

They were the same in my Rev 2 kit.

73, Mike KK7ER

Same experience here as others have reported.

Distracting clicks, severity varies by band, less intense with AGC off. Fiddling with AGC settings can mitigate somewhat. Present with dummy load or antenna.

Kit built QMX Rev 2 board, 12v RWTST, hi-bands, FW17.

I can collect more data if desired.

73 Matt

Started my build, but I got to L502 & T401 and I'm stuck. The manual calls for both to be FT37-43. However, one of mine is a dull black, while the other is shiny black. Are they the same? Now I'm not sure how to proceed. I do have an FT50-43 here that I could put in the L502 if necessary.

(BTW, I put in a ticket to QRP Labs help desk, but I never got the test email. I think it was eaten by the internet. That's why I'm asking on here, as I don't think the answer from there will make it through.)
--
73, Dan? NM3A
There are moments when everything turns out right .... Don't let them alarm you; they pass.?

-Jules Renard

Hans,

One bug, and one idea.

Bug:? When doing RF image sweep immediately after startup via console (doing nothing else), the graph shows no rejection on 80m.? When I switch bands and come back to 80m, I get -25dB rejection and it works.? Not sure exactly what's going on, but I'd suspect something isn't getting set in line right.

Idea:? I've noticed that the BPF for 40m, 60m, and 80m are all the same BPF tap (Full inductor, 1200pF) using IC402 Y3 / Pin 13.? I feel like it wouldn't be too hard to put a another capacitor in C403? (DNP in 20-80m rigs) and have pin 10 selected for 60/80m (or just one of them, depending on what gets tried) and adding in a dozen turns or whatever onto L401 that cross over the incoming pin from RX_IN.?

Discovered this while tuning my BPF, I think I left a turn off L401, all the BPF filters are up off center, but then I was wondering why 60m/80m was so far off center, finally realizing it's shared with 60m/80m.?

Is there a way to manually set the BPF configuration for 60/80?? (Or is there a way to do a test build that I can load?)? Since I can't do it myself since the firmware isn't open, I have to ask.? (Not criticizing there, I get why you wouldn't want to release the source code).

Alrighty, I got the replacement PCM1804's in, and the replacement went off without a hitch.? I cleaned up the pads, put down a touch of paste, hit each pin with the knife edge soldering iron, gave it a good IPA clean, and it worked.? The only victim of all my debugging was 20m, first initial try and it was getting no receive on that band, which I traced back to having left the BPF split toroid (L401) unsoldered at the mid tap.? Putting that back in and it RX's just fine.? I can't say I enjoy the user interface as much as my KX3, but hey.?

I'll have to start using this bugger and get some time on it now that it's up and running.? Thanks for the suggestions folks.? I'll ask another question in another thread soon likely.

Cheers,

Martin

Sounds good, I just cleaned the backside, I didn't really need to immerse the whole thing, but a good scrubbing with an ultra-soft toothbrush leftover from the dentist and 99% IPA did the trick.? The QMX of Theseus lives......!

Hi Martin,?

I used 91% isopropyl alcohol and a very soft toothbrush. ?I was gentle but did the whole bottom, which I have rarely done in the past. So much cleaner. ?The shack has good magnification so looked it over well. ?My recommendation is go gently, especially on the SMDs and ICs. ?And, I would do it on the next one!

73,
Mark N8MH

Hi,

What is the washability of the main PCB?? Naturally, I wouldn't wash the display/encoder boards, but I might like to remove some of the flux I've added in the QMX of Theseus (as I'm now going to call it).? I normally wash my PCB's with technical grade IPA and/or hot water with a soft toothbrush for scrubbing before drying really well, but since I didn't design this PCB, my biggest concerns are the audio jacks.? Anything else I should be concerned with?

[*taps foot waiting for Fedex to deliver new AD codecs*]

On Thu, Mar 14, 2024 at 05:03 AM, Charles Johnson wrote:

so you're loading down the audio output amplifiers significantly more when you plug into a line-level input.

It's the other way round, Charles. A lower impedance load will place a higher burden on the output amp.

That's what I get for posting way too late at night! My overall point, though, remains: namely, that due to the different impedances, the performance of the output audio amplifiers will not be exactly the same, thus possibly explaining why clicking was being heard in ear buds, but not via a line-level input. Due to the comments on it going away at low volumes, however, I'd lean towards the impedance differences merely amplifying (no pun intended) the true source of the problem, rather than being the problem.

Charles Johnson
KF4AYT