\unless we are talking about different things, contrast is a small pot on the LCD board.? There were three or four options, on the version 1 using different resister values and or locations for brightness.

Bob

No Steve, it's not uncommon. I have this same situation, and I've found at least two others besides me!

/g/QRPLabs/message/116786
/g/QRPLabs/message/116338
/g/QRPLabs/message/116762

No power up, therefore no bootloader and no visible USB drive. Only 5 to 8mA while pressing the left encoder, nothing after. In my case, I've put my PSU modules, display and button board, one at a time onto an older Rev 1 low band QMX that I built in Jul/Aug '23, and they all worked there, so not PSU problem, must be the rev 2 main board, obtained in Dec '23.

George, M0HLP

My pre-assembled QMX arrived a few weeks ago.

Today, another issue arose in my 80-20 QMX, but this one is a show-stopper:
CW keying, (whether A, B, Straight) stops working.? No sidetone.? No RF out.? When this happens it is necessary to to a factory reset, and wipe out all of my settings.? DC power, antenna/load, and settings are correct.??

Older issues continue to be:
(1) Loud pops on 80 M, when the key or paddle is released (reported by other users) not as bad on other bands.??
(2) After choosing a preset frequency, the VFO encoder has to be twisted and then returned to frequency - otherwise the frequency is only in the display, and you're not on the air.
(3) I opened the case to verify the diode mod was installed (yes)? and noticed dull-colored (cold?) solder joints on the PCB
(4) SEMI-QSK not yet implemented?? It sounds the same (POP POP POP) as full QSK.

Does someone repair QMXes?

Thanks & 73,
W6CJ
Jay

I would like to know how to build a 160 meter QDX-5. I am working a? few stations with My Phaser..
There are a lot of stations on the band running FT8

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I wonder if it will be revised. I say this, because the previous owner was unloading all the build parts for the WM-2.

I just emailed Dennis N1IMW, the new owner at Oak Hills Research.? The WM-2 Wattmeter will be available in February.
Great news !? I'm saving my allowance.
Jim WB4ILP?

I can easily endorse the Oak Hills Research QRP watt meter if you can find one used. I built mine years ago and it compares accurately with my Bird.

Ken
N0VA

40 Meter QCX Plus. Has TXCO plus neat little flip up stand. Meets all factory specs, 5 watts on 12 volts, 6 watts on 13.6 volts
$105.00 shipped or $110.00 shipped using PayPal..
I monitor my email, all info good on my QRX page.
Thanks, Gary W0CKI

Hello,

Last week I reported success in building my low-band QMX Rev 1 per the latest manual (configured for 12V). I was very careful during the build and this being my 5th QRP Labs radio kit, I felt it went very smoothly.

Everything worked great… for about a week. This morning I plugged it in and the radio would not power up. I can hear a brief pop in the headphones when I depress the encoder, but the LCD remains blank and there is no other indication that it is working. I also tried plugging it into the PC to see if somehow the firmware had reset itself to factory configuration, but the PC wouldn’t recognize the board at all.

Can anyone suggest a starting point to figure out how to troubleshoot this?

Thanks in advance & 73,
Kevin

--
Kevin Culp, KZ3L
Warren County OH
Grid Square EM79

Lynx,

The reset would be after loading the new version.

Lynx,

Have yu tried a factory reset to clear the EEPROM?

73
Evan
AC9TU

I used 1/16 Watt resistors and a BAW62 diode because that's in my junkbox. It works FB Rob.

Heckits.com sells a clone of the OHR power meter. It has a few upgrades and works very well.?
--
73, Dan? NM3A
There are moments when everything turns out right .... Don't let them alarm you; they pass.?

-Jules Renard

Lunx,

I guess we will need to wait for a response from Hans.? I am out of ideas.

73
Evan
AC9TU

On Sat, Jan 20, 2024 at 12:07 PM, Evan Hand wrote:

Lynx,

Have you tried downloading another copy of the firmware?? Maybe the copy you have is corrupt?? Not likely, but a possibility.

Yes, I have also try v1_06 and v1_09, they also not work correct. But this two version I have not test the CLK0 and CLK1 waveform. v1_10 firmware I have downloaded two times and they are the same.

73
Lynx
BG7JAF

On 20/01/2024 14:42, Hans Summers wrote:

they all work the same.

The only difference I have noticed using other uBloxes (with a U3S) is that satellite data does not always display correctly. It can sometimes be almost corrected by configuring so that only the required NMEA sentences are sent.

The time sentence is always read correctly.
Some QRP Labs units use a PPS for frequency setting, again not essential.

73 Alan G4ZFQ

I was in contact with the new Oak Hills Research owner (sorry I don't recall his name and call).and he is planning to reopen the business as soon as possible.
I was saving for the wattmeter also.? Apparently it is an excellent product.
Jim WB4ILP?

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Hi folks,

Before I built my QMX I bought a CQV-SWR120.? It's about $50 on eBay and of course comes from China.? I got it for my IC-7300 initially and when compared against another wattmeter it's not linear at all.? You can set the reading at say 100Watts and at 75 or 50 watts it's off by 10 percent or more.? However, with the QMX at low power it seems very accurate.? I don't have a lab type meter to measure it against but using the average between all, this one is close.? It has an alarm feature that you can tighten up so it will alarm on elevated SWR before the QMX shuts down.? It also has the ability to adjust the reading so if you have a good quality meter you can bring this in very close at 5 watts.? It has an internal battery that will last for several POTA outings.? Charges via a USB-C connector.? And it's small.

Sorry I meant for using the beacon mode for wspr. I will amend my original message.?
Sam