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Thank you very much Hans. I really appreciate it.?

Alan,

For Wsjtx, yet it isn't needed. Not all people live in FT8 land either.

73,
Cliff, AE5ZA

On 24/11/2022 11:51, John Kirby wrote:

Split (mode THANKS) works very well when the fox calls? "CQ UP 1"? (1 kHz for example)

John,

According to the manual WSJT-X has two ways of working split without the radio contributing. Basic no split changes the audio frequency, not always ideal, but "Fake it" tunes the radio.

73 Alan G4ZFQ

?
Split (mode THANKS) works very well when the fox calls? "CQ UP 1"? (1 kHz for example) keeps the pileup off the fox so all hounds (troops :>) can hear the fox

72 73
John
N3AAZ

On 24/11/2022 08:58, Vojislav [YU4HAK] wrote:

I use 12v from a running computer PSU molex (yes, the horror!)

I am not horrified:-)
I have used the PC supply for many years, I'm so used to it I forget and you reminded me.
I use a simple LF iron-cored choke and capacitors as a filter, have never been aware of any problems.
In fact for the older soundcard SDRs it helps to make ground loops easier to eliminate.
And also 5 volts USB, a simple filter keeps it fairly quiet. Many good modern SDRs are USB powered.

73 Alan G4ZFQ

I use 12v from a running computer PSU molex (yes, the horror!) But it is actually not that noisy, barely noticeable on the waterfall. It is a high quality PSU though. I also tried a standard 12V 5A?adapter and that is ok too. A pack of old 18650 batteries is of course totally noise free, but if they are not new and high quality, voltage may drop once you start transmitting. My advice is no need to go crazy with fancy noise free adapters for QDX, as its filtering capabilities are amazing.

Hi Michael,

As others have suggested, I wrap 10 to 14 turns of coax through an FT240-31 toroid core (based on work done by K9YC) and I locate this choke approximately 0.05 wavelengths (on the lowest band) from the feedpoint of the EFHW (based on work done by AA5TB which I also confirmed via modeling).? Doing this does a great job keeping RF off the outside of the coax shield between the choke and the radio.? Also the outside of the shield between the feedpoint and the choke acts as an adequate counterpoise so you don't need to install an additional counterpoise wire.? The choke also helps reduce common mode noise that travels from your shack up to the feedpoint via the outside of the coax shield and this therefore often helps reduce your receive noise floor.? It also makes the SWR much more stable (repeatable) as it eliminates the outside of the shield between the choke and your radio from being another variable (additional counterpoise) that would otherwise alter the SWR depending on how it's coiled up, what its touching, etc.

73,
Don (wd8dsb)?

Hi Derek,

I built a 30 meter QCX Mini a few weeks ago and followed the procedures in the video that EI5EM provided you the link to.? I was able to get exactly 5.0 watts out using 12.0 Vdc and I measured the power output using my Oscilloscope across my 50 ohm load.? I too had to remove a couple of turns from L3, and I not only noticed a change in output power by changing the spacing on the turns, but also how close to the toroid core my winders were.? When winding the cores I actually push each winding tight to outside diameter of the core using my thumbnail when I'm winding the core, and also pull each turn of the wire taught to the inside of the core as I'm winding it, and I even noticed an improvement in output power when each end of the winding was pressed tight to the core on its way to the point where it gets soldered to the circuit board.

It really is an amazing radio, and I'm now going to start building one for 40 and then one for 20 meters.
Don (wd8dsb)

I got one of these for a string of LEDs:



12VDC, 5A, available with a 5.1mm plug or little screw-on terminals.
USD$12., free conus shipping available with Prime or if your order
exceeds USD$25.

My first test application is a string of LEDs I am using for an
aquarium light. The supply is probably IP65 (water-resistant). I'd
feel safe with it next to my QDX out in the field. My LED string
draws 2.5A, and this supply gets up to about 37C (100F) in use. In
comparison, its predecessor is a 1A 12V Lambda linear open-frame
block PS that happily delivered the 2.5A but ran at 165F. With an
almost-silent 2 1/2" muffin fan on it, it cooled down to 110F. That
surprised me. The supply before that was a "1.5A" wall wart that
lasted only one night.

I haven't done any electrical testing on either the Lambda or this
little Peculiar (see the pictures in the listing) supply, but both
worked fine, once tweaked for this application.

This Peculiar supply, both my QDX cases (revs 3 and 4), and my
RasPi4's aftermarket black anodized case all match very, very nicely.
I'll try to get a photo this weekend.

I'll also try putting Little Peculiar on a 'scope and do load-testing
and input voltage testing to see what happens. I'll also try a cheapo
12VDC - 120VAC inverter that I know is at best a modified square wave.
If it's not noisy on line AC AND on the inverter, then it's a good
cheap possibility. Otherwise, the fish get it.

73
Jim N6OTQ

P.S I am not sure whether this Peculiar supply will have enough
headroom for the RasPi4, the QDX, a powered USB hub, and anything
else. But my inverter has more than one 110VAC outlet and it SAYS
"400 watts," Based on the last two supplies taken out of service on
the fishy LED project we all know what power supply labels are worth.
At 100% efficiency, 400 watts - 33 amps at 12VDC. Right.....


On Wed, Nov 23, 2022 at 6:13 PM kg4lac via groups.io
<kg4lac@...> wrote:

I'm considering the ALINCO DM-330MVT. Seems a decent power supply and gets good reviews.

I'm considering the ALINCO DM-330MVT. Seems a decent power supply and gets good reviews.

On 11/23/22 14:28, ve3ega wrote:

Ed, Here is my cooling arrangement!
This is the small Heatsink

+1, Thanks appreciate that. :-)

--
Linux Home Automation Neil Cherry kd2zrq@...
Main site
My HA Blog
Author of: Linux Smart Homes For Dummies KD2ZRQ

I had a similar problem a couple of weeks ago and it turned out reflowing all the enameled wire solder joints fixed it. The antenna wasn't connected to the receiver!

Will load the blob on Friday and give it a whirl.? Thanks Hans!? Looking forward to 2200 m also.? We have a specific application for that on Rx here in the US outside of Ham radio.

Well start with the knowledge you have. Open the tuner and the build instructions on a screen. Check the construction carefully. Then use an ohmmeter to make continuity checks. Believe something isn't connected right when it isn't working. Others have been there done that.?

Curt

Hi, Terry. Yes, Ive used different USB cables. At this point I managed to get audio from the QDX to WSJT-X. Now the problem is trying to receive a signal more than just the noise.

? ?...doug, K6DRK

Hello everyone

Now that I have my EFHW set up, I’ve sent some test messages I’ve saved. I’ve noticed the tone seems distorted or “scratchy” at low volumes. It seems to get cleaner by increasing the volume. I’d there something specific I should check or troubleshoot?

Thanks,?
Michael

--
KD7PTZ

Thanks Curt

I’m going to need to do some research as I’m not super familiar with the circuits or troubleshooting yet. I was very careful during assembly but clearly there is something amiss.?

Michael
--
KD7PTZ