I'm building the QMX and have the L401 installed and ready to solder.

The manual says to cut the wires underneath the board and solder.

Does this mean to cut the loop into two separate wires and solder them in the same hole ?

If that's the case, why not keep the loop intact ?

Many thanks to anyone who can provide some clarity !?

Beautiful setup. I can see some future directions for antenna experimentation in my future! Thanks!

开云体育

I meant C105 is not shorted when I uninstall PCB 2.

Wayne

OK, all. Just to keep you informed in the case something gives you an idea to send to me, I am finding C105 on PCB 2 (the 3V3 board) shorts when I install the board. It is not shorted when I remove the board.

Wayne

Wayne,

The zero power out issue that caused me to start this message thread has not yet been resolved on my unit.

With some great input from this thread my next step is to pull out T501 (the power amplifier transformer) and rewire it.

I should have time to get to this today or tomorrow and I will be posting my results.

Mike KC2EHR

John,

As suggested, I checked the current draw on IC407 which appears okay at 33mA.

Also, I was unable to receive any IQ output via USB and HDSDR (works fine with my other QMX)??

I've realised today that I my previous statement that the outputs IC405 and IC406 "seem okay" may be questionable as I'm learning how to use an oscilloscope again for the first time in 40 years ;))

73? Chris - M0KNF

Thank you, Evan! Now, maybe I can figure out where the 12V and ground are shorted. It's not at the pins, so I'm a bit baffled.

Wayne

Inovato Quadra, an Amazon monitor, two cell phone charger batteries, voltage regulator because I did the 9v power winding, cw key, harbor freight 3800 case, and all the needed cables (quadra came with mini keyboard and trackpad). BNC binding and 66' of wire in the cable bag too for "emergency" radiator, but I use an MC750 vertical (not pictured).

I can run the Quadra headless, and may do so in the future to just bring my tablet along. For now, I use the Quadra for FT4 and JS8, my tablet to run FT8CN. This is my $350 POTA kit!?

Just posting this to give folks an idea or two. If I were doing it again, I'd switch everything from its current side to the other. Also be advised that WSJTX decode taxes the Quadra capabilities at time...I switched it from deep to fast and that helped a lot.?

Firmware 17 is fantastic, FT8CN works flawlessly with it, and I can't wait for SSB capability!

And for WSPR and for auto-ATU and for when SWR is iffy.

73, Mike KK7ER

Udo: I really like your setup!? Is that the smaller 3000mah talentcell?? I struggled between it and the larger 6000 that I ended up getting.? I figured the larger one would let me have it operational for considerably longer, though tbh I'm not sure I'll ever need it off grid for as long as it'd allow me to be.? But, with the Pi and its screen working off the battery too, I felt better with the extra capacity assurance.? And it's the same footprint as the tuner which was another plus.? I may end up also getting the 3000 to use with the QMX alone with a resonant antenna (tuned efhw or dipole) separate from this loadout.? I like your paddles - n6ara right?? I have boards coming for vk3il's pressure paddles that'll replace these, they'll be much smaller (or, thinner anyway) and let me space out stuff and not need to cram all the bits in the corner.

DK4BN:?I just took the antenna out for the first time on this trip as well.? It is not finished and I haven't done good tests with it yet, but here it is.? It is built on 1/2" PVC (0.839" OD, or 21.3mm) with 22ga BNTechgo wire off Amazon (my measurements: insulated dia 0.027", 0.6858mm, and uninsulated 0.0253", 0.6426mm) and 4' whip (actually 46-3/8").? Top of former has a m4 bolt to accept the Elecraft whip.? The tap screws are m3, and spacing between coils is (or, was) whatever dia the m3 washers are - this GREATLY affects the inductance as it breaks up one coil into multiple.? I don't bother with the math on this, since I'm going to have to do trial and error on the coil winds anyway?(though there's a multiple coil inductance calculator that can be used).? I tuned it there in the park before getting on the air with it (except for 40m).? Here is a closeup of the coils if you'd care to count winds.? Note there's a length of wire (2-3" running from the bnc connector to the bottom of the former through that hole to the first coil.? Bottom is 20m - I had to remove 5 or 6 winds to bring it up from about 11MHz to 13.7MHz hence all the slack.? Removing another wind and keeping the coil tight would have taken it too far above 14 so I spread the winds out to decrease inductance a little and now it's spot on 14.0, and to tweak it to higher in the band I can just pull the whip in a small amount.? Bottom+Middle is 30m and where it is is just right, with pulling the whip in a small amount.? Bottom+Middle+Top is 40m, which I have not tried yet other than observe on the nanoVna and it does not have a nice dip.? My guess is there is not enough coil and I need to add more, but I'm out of space with this former and I'll probably rebuild and move this all to a slightly longer one (it's not glued yet).? But, where it is I get ~3.5:1 SWR on 40 which is tunable (and did in fact tune to ~1.1:1) with the atu-10.? Once I get it all where I like it I'll wrap in heat shrink leaving holes for the taps.? I hope this helps

Hi Wayne,

I must apologize to the original creator of the attached PDF.? I can not find the post that included this drawing.

I have attached the pinout for the power supply modules that have not changed since the first revision.

73
Evan
AC9TU

Whoops, sorry... I've just realised that my working QMX is actually a Rev1 version:-/

73 Chris - M0KNF

Hi, all. I'm wondering if this problem has been resolved, and if so, how was it resolved? I'm having the exact same problem Mike had.

Thank you,

Wayne KB4DSF

I entered a support ticket on the help desk last week, but so far no response. I am wondering if anybody read it?

I received my second QMX, the high bands model, with the case option last week. Order 84278. After inventory of the parts I found that two right side panels were included, and no left side panel (audio,key, DC). I've got the QMX up and working, making contacts. I am hoping to hear that a replacement audio-key-DC panel is on the way. ?

Ernie W8EH

I use one for the rig and a second one for everything else.
Both stack neatly in a backpack.


That's a QCX mini, a QDX HB, and the 50W amp.
But a QMX and NanoVNA also fit in place of the QCX and QDX.

73, Mike KK7ER

ok...maybe the other pin is 12VDC out? I'm just having trouble finding where these pins are shorted. It's got to be somewhere else on the board.

Wayne

hi Jason, great stuff, the talentcell I have too, my tuner is the pocket transmatch by Kanga, tiny paddles and a very cheap speaker. simply have a look at the following:
my /p setup