On 28/08/2023 10:56, Dave ZL1TIU wrote:

Tried a factory reset,

Dave,

Yes, this has been reported on various QRP Labs rigs. Not a common thing but sometimes cures strange problems.

The diagnostic LED is now off and

the QDX is receiving.

Note that light has no meaning for the user and has been removed on later versions.
Also note the audio input analysis is for looking at the transmit input. Read the manual, not a simple setup and for interest rather than diagnostics.

73 Alan G4ZFQ

This is the stand I 3D printed from Thingiverse, there are several options available.?

I have an original version QDX, which puts ~3 W into my 20 M dipole about 25 feet above ground. ?It works well and has produced many FT8 contacts, though many of my calls go unanswered on the crowded band. ?I figured another 10 dB of power would be a big help. ?I have a 50W class C amplifier, which I use with my QCX+, but the original QDX does not provide a 5 VDC output to activate the amplifier. ?So I built a switch that taps a bit of power from the QDX to the amp and provides the 5 VDC to place the amplifier in transmit mode. ?The switch is inserted in the coaxial cable between the QDX and the amplifier via a BNC tee, as shown in the photo. ?I used a 9V alkaline battery for the DC power source, for convenience (beneath the circuit board in the photo). ?No current is drawn from the battery during receive, and only ~7 mA during transmit (mostly to power the red LED in the amplifier. ? But this is not a good long-term solution. ?The turn-on time for the transmit signal is of the order of a mSec or so, but the “hang time” or turn-off time is about 250 mSec. ?This is acceptable for FT8, but would need to be shorter for cw operation. ?Reducing the values of C1 and C2 to say 10 nF should reduce the turn-off time, but I didn't experiment with component values in the circuit. ?With the amplifier the rf output power is now 35 W, the 10 dB improvement I sought. ?This has improved the overall contact success rate, as anticipated.

73, ?Ben ?K0IKR

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If history (and following along in this group) is any guide, of course there will be PCB revisions as required and as Hans has to order new batches. Sounds like he already has minor tweaks to the SMPS boards in the queue.

Also, if history is any guide, all firmware will run on all revisions. Rev 1 QDX and Rev 5 QDX can all run the latest QDX formware, for instance:
/*
Assembly manual for PCB Rev 5 (document version 1.18f published 04-Apr-2023)
Operating manual for firmware 1_10 (document version 1_10 published 19-Jul-2023)
*/

73, Willie N1JBJ

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I'll make the popcorn...?

I have a weird problem. No waterfall. The rig goes through normal fire up. Don't know if there is output or not. I use my tablet, ft8cn and an end fed log wire and am on 7.074 mHz.

HIF

Hi Group,

I don't know if this has come up here before (a search turned nothing up) but thought I would share the stands I originally used on my (tr)uSDX radio's.? They work equally well for the QMX and QCX Mini's.?

73,

Robert, WA2T

In doing due diligence, one has to ask the tough questions. Does management see a Revision 2 PCB board on the way with all the known fixes on it? Would new firmware depend on having the new Revision 2 PCB board leaving the Revision 1 QMX units behind? Yes, this is a tough question, but a valid concern in making a decision. Thanks in advance, Billy
--
N5SE
Billy Wayne Moore
7066 Shady Knoll Ln
Willis, TX 77318-6324
Phone: 936-537-2975???

Tried a factory reset, (I had previously set the audio gain to 80db) I also increased the audio gain to 90db. The diagnostic LED is now off and the QDX is receiving.

i have just had the same problem, (like the qcx mini had) i was pulling the power supply plug from the QMX when it was turned on, (as it wouldnt turn off). and smoke came from the SMPS board. Great this just gets better
Mike

I think you mean a? Stretch goal.. that's what such things are called? in Oz. AKA;? "the project manager sweats the staff "

I've built both a QDX and a QMX. The QMX works very well. I've never been able to get the QDX to receive, I thought it was just my location and bad aerial but the QMX disproves that. The QDX and QMX both have about the same transmit power of around 4watts across the bands. Checking the QDX TCXO shows it to between 2 or 3 Hz of the correct frequency (or my counter may be off).RF sweeps and audio sweeps appear normal however the input analysis shows 'no signal'.The diagnostic light is on but this may be normal. The T2 transformer and L12 bandswitch coil all show correct continuity. I've run out of ideas, Has anyone any suggestions and is the diagnostic led of any help?

OK

No need to respond to my last message : the problem was that it needs to see 5V and I only had 4.93 ... so I adjusted the voltage divider a tad
Now up and running properly, so I know the only damage is on the 5V regulator board



Cheers
Rick

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I have lost audio several times on my QMX.?
A Hardware reset via the menu brings it back?