开云体育

Thanks! I went out and bought a syringe with flux paste, but it's very hard to dispense and apply it. What you have seems a lot better.

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On Thu, Mar 20, 2025 at 02:31 AM, N4REE - Bob wrote:

One thing I noticed, probably general and not specific to this release, is that during TX the power meter does not really follow voice peaks very well compared to an external peak reading meter or watching the signal on the waterfall display.? ?This may be due to a low sample or update rate on the meter and may just be the way it is implemented.? It has caused me to wonder if I am getting good output but when I check the external peak reading meter and waterfall it confirms that I am getting good output.

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Brien - KE7WB?

This is the circuit I use for my Heil microphone, this just has a TS connector, no ring.

Chris, G5CTH

It could be one of the protection diodes on one of the buck converter boards. Those are D106 and D109.?

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73, Dan - W2DLC

Selling QMX+ V1 unbuilt kit. $125 ? Will include case and free shipping to lower 48. ?I just have too many QMX’s HI. ?Email is good on QRZ. ?

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Trevor (N0YMA)

Thanks, Stan.

On Thu, Mar 20, 2025 at 09:08 AM, Daniel Conklin wrote:

I noticed, as some others have, that the built in mic is picking up my voice and other sounds in the room while I am in the mic gain adjustment mode in the terminal.

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73, Dan - W2DLC

I just saw the other thread where Hans explained that the internal mic is used as the reference for the noise cancellation.

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73, Dan - W2DLC

It might make sense to ship the board with only the small parts stuffed, that should be most of them.

The few large parts could be obtained locally.

Fragile small parts or those mounted vertically could be in the same envelope, soldered in place after arrival.

Shipping in an envelope seems more likely to avoid trouble at customs.

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Shipping in an envelope is more likely to result in damaged parts.

Has to go through mail sorting machines.

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Jerry, KE7ER

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On Thu, Mar 20, 2025 at 08:45 AM, Sardar (AC8L) wrote:

Successfully built my first transceiver ever, the QMX, a few weeks ago. ?As a novice with electronics, it felt amazing to complete. ?I have tested it several times in the backyard, and everything worked as it should and made several contacts.

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Got out to a POTA park today for my first POTA activation with my QMX, and it will not power on. ?I’m using the same cable and battery I have used in backyard testing— a PD power bank with a trigger cable for 12V (which is what I built it for).

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Field troubleshooting so far:

I’ve ensured that battery has power (96%), and I’ve removed and reinserted the power cable several times. ?

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I removed the enclosure but can’t remove the buttons as my Leatherman multitool small flathead had broken off many years ago, oops.

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At this point, I’m about to head home to finish testing from the house.

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Thanks for your help,

Mallory KD5ZZU

Any built for the (tr)uSDX will have the correct wiring.

Welcome to the world of SSB.

Everything may be fine.

Turn compression up to about 10 and you should see a bump up in output power.?

With SSB, many/most external wattmeters are not fast enough to catch the true peaks of the transmitted voice waveform.? And on top of that, the peak-to-average power ratio of transmitted voice is very high, so an average-reading power meter will show only a small percentage of the actual peak output power.? Turning compression on increases the average power, at the expense of some distortion.

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The power peaks on QMX will be 4.5W (if your QMX does 5W, and your mic gain is set properly), due to the 90% drive level default setting Hans described.? You won't be able to see those on a power meter, but should be able to verify with an oscilloscope.

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Stan KC7XE?

Do any of the commercially available hand microphones for existing QRP radios work with the new QMX SSB?

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Or perhaps pre-wired adapters for those mics already in the marketplace?

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Bill? W3WJ

On Thu, Mar 20, 2025 at 01:51 PM, Joseph Slezak wrote:

When retrying, the radio gets into a boot loop where the screen clears, backlight turns on, and FW info is displayed. Before getting to the VFO it powers itself off now. Upon trying a hard power cycle (removing power supply, reapplying 12.0v), and clicking the Vol knob to turn on, it booted again, never made it to the VFO screen and made a loud pop. Something died hard. Magic smoke

Joe, this sounds to me like a problem related to the 5V SMPS board. Power off by itself could be a result from a broken D101. Which Rev. is your broken QMX? There was a known issue for one or two revisions, a short between Q103 and Q105 (see ). Maybe for your QMX it was close to this short and for some reason during your last actions it came to a full short. And maybe triggerd by this you have got more problems.

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Maybe the loud pop came from C107. For early revisions it was rated 6.3 V but now 10 V. There were some reports about burned C107.

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73 Ludwig

Relays are even thicker. Plus group buy manager will solder female programming socket under the pcb which will make the package about 2mm thicker. So cheap envelope shipping for the ATU board is no go.

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73,
Sardar (AC8L, 4K6SA, VA3DUA).

All of my old gaming headset adapters short the tip and ring, putting input mic audio on both.? So I can't use them for qmx.

Thank you, Stan, for being the lighthouse in the storm!

Sometimes we all need someone else to shine a light into our rabbit-hole and help us back out.?

Stan KC7XE?

I finally bit... Ordered some .3mm (28awg) colored copper craft wire from Etsy.? Shipping included, it was under $10 for 100 meters of wire.? On a per inch basis it is 4x more than a quarter pound of one color from Amazon but 100 meters of wire will wind more? toroids than I am likely to need for the next few years...? (I tried using sharpies to color the wire, but it was hard to see and made a mess on my fingers)

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Interesting thought.

Karl wrote:

What should the AGC settings be?

First just turn agc off and see if the nature of the issue changes.

If you have the first parameter turned low, like S4 or so, it could be cranking your gain up so you hear the tones much stronger than they are.? This would happen in CW mode.

Measuring again and seeing what the 10 volt rail does during transmit, I see that it drops to about 9.85 volts on the rail and 9.37 or so at the input to Q508. This gives something like 9x10^-7 amps leakage through Q508. The spec sheet for bss123 says that's out of spec as it should be 10x10^-9 amps of leakage even at 20 volts, but I'm not sure that that small amount of leakage would have been enough to blow up the Mux ICs.?

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I may change Q508 as well just to be safe.

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Greg

Just to see how far up my head has been during this 'cranial-rectal inversion' I did a continuity test C422 to R413/R416 which was, of course, successfull!

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Thank you, Stan, for being the lighthouse in the storm!

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73
Karl
KI4ZUQ