#qdx — Public Fediverse posts
Live and recent posts from across the Fediverse tagged #qdx, aggregated by home.social.
-
It worked for many months.
Wired for 12 V supply. ATU said it put out 4-5 W.
Then after a storm or three, it stopped transmitting. Might have been static zapped by storm. Might have transmitted in bad SWR as vertical antenna flexed in storm.
It still receives, the microcontroller talks on USB serial, I put a 50 ohm dummy load on the BNC port, and can tell it to test transmit, but hear nothing on a nearby KX3.
BS170s are now hot while idle. A short?
I need to find the fault.
-
My effort to replace the four BS-170 transistors and to add protective zener diodes failed.
The microcontroller still works. Over USB it's possible to "screen /dev/ttyACM0" and get to the diagnostics, to trigger a test transmit into a 50 ohm load.
But no signal comes out.
Worse, even idle, the PA transistors and output transformer are hot. They shouldn't be!
Stare at schematic, thinking.
Might be time to write it up, bag it up, set it aside, buy replacement.
-
Got a little QDX radio that isn't working.
Connects via USB, just looks like a sound card and a serial port.
It works like a penny whistle!
You blow on the end of the USB cable, and it measures the zero-crossings of the audio waveform, figures out the frequency, adds maybe 7 or 14 million to the number, then squeaks out a 4 Watt RF whistle to the antenna.
Except the BS-170 N-channel MOSFETs probably popped from high voltages from momentary bad SWR.
So no happy whistling.
-
A view of my cockpit for my "Early Bird #pota #parksontheair activation. @qrplabs #QDX #qdxdigital #qcxmini #qrpradio #cw #morsecode #PanasonicToughPad #qrpguys #minituner #linkedefhw
-
A view of my cockpit for my "Early Bird #pota #parksontheair activation. @qrplabs #QDX #qdxdigital #qcxmini #qrpradio #cw #morsecode #PanasonicToughPad #qrpguys #minituner #linkedefhw
-
A view of my cockpit for my "Early Bird #pota #parksontheair activation. @qrplabs #QDX #qdxdigital #qcxmini #qrpradio #cw #morsecode #PanasonicToughPad #qrpguys #minituner #linkedefhw
-
A view of my cockpit for my "Early Bird #pota #parksontheair activation. @qrplabs #QDX #qdxdigital #qcxmini #qrpradio #cw #morsecode #PanasonicToughPad #qrpguys #minituner #linkedefhw
-
A view of my cockpit for my "Early Bird #pota #parksontheair activation. @qrplabs #QDX #qdxdigital #qcxmini #qrpradio #cw #morsecode #PanasonicToughPad #qrpguys #minituner #linkedefhw
-
It was a 40M @qrplabs #QCXmini #CW #MorseCode & 40m/30m #QDX #FT8 Early Bird 4th of July #POTA #parksontheair activation Almost had some early fireworks display if I only could have completed a FT8 #QSO with Bob @KF0UNK My #QRP signal just didn't have enough oomph to break through the traffic #AmateurRadio #HamRadio
-
It was a 40M @qrplabs #QCXmini #CW #MorseCode & 40m/30m #QDX #FT8 Early Bird 4th of July #POTA #parksontheair activation Almost had some early fireworks display if I only could have completed a FT8 #QSO with Bob @KF0UNK My #QRP signal just didn't have enough oomph to break through the traffic #AmateurRadio #HamRadio
-
-
-
Ok, just discovered digipi.org, which seems like a perfect combination for the QDX for doing digital modes on the go. Here I’d been thinking I might have to go buy a laptop…but here’s a solution for $40ish. #ft8 #qdx #raspberrypi #digipi #hamradio
-
I built a #QRPGuys 40-10 #Minituner a few years ago but never built a wire for it. Thanks to current #Geomagneticstorm conditions, I built a 40 -15 Meter Linked #EFHW that I can use with my #Youkits #YouKitsHB1B #HB1B and my #QRPlabs #QDX. #AmateurRadio #HamRadio is so much fun!
-
I built a #QRPGuys 40-10 #Minituner a few years ago but never built a wire for it. Thanks to current #Geomagneticstorm conditions, I built a 40 -15 Meter Linked #EFHW that I can use with my #Youkits #YouKitsHB1B #HB1B and my #QRPlabs #QDX. #AmateurRadio #HamRadio is so much fun!
-
I built a #QRPGuys 40-10 #Minituner a few years ago but never built a wire for it. Thanks to current #Geomagneticstorm conditions, I built a 40 -15 Meter Linked #EFHW that I can use with my #Youkits #YouKitsHB1B #HB1B and my #QRPlabs #QDX. #AmateurRadio #HamRadio is so much fun!
-
I built a #QRPGuys 40-10 #Minituner a few years ago but never built a wire for it. Thanks to current #Geomagneticstorm conditions, I built a 40 -15 Meter Linked #EFHW that I can use with my #Youkits #YouKitsHB1B #HB1B and my #QRPlabs #QDX. #AmateurRadio #HamRadio is so much fun!
-
I built a #QRPGuys 40-10 #Minituner a few years ago but never built a wire for it. Thanks to current #Geomagneticstorm conditions, I built a 40 -15 Meter Linked #EFHW that I can use with my #Youkits #YouKitsHB1B #HB1B and my #QRPlabs #QDX. #AmateurRadio #HamRadio is so much fun!
-
Since my QTH continues to be inundated by storms, I need to take advantage of them and build my other @qrplabs 20 - 10 meter #QDX #qdxdigital before Ten goes away. #amateurradio #hamradio #FT8 #wsjtx
-
Since my QTH continues to be inundated by storms, I need to take advantage of them and build my other @qrplabs 20 - 10 meter #QDX #qdxdigital before Ten goes away. #amateurradio #hamradio #FT8 #wsjtx
-
The #QDX is alive(-ish!)
I finished winding all the toroids today, and tried to get it "on the air" through a dummy load.
It connects to WSJT-X fine, but my cheap USB-A->B cable is sucking up RF like crazy and crashing my interface immediately on transmit. So, I can't actually check transmit power because transmit stops immediately...
Anyone have ideas on how to remedy this?
-
The #QDX is alive(-ish!)
I finished winding all the toroids today, and tried to get it "on the air" through a dummy load.
It connects to WSJT-X fine, but my cheap USB-A->B cable is sucking up RF like crazy and crashing my interface immediately on transmit. So, I can't actually check transmit power because transmit stops immediately...
Anyone have ideas on how to remedy this?
-
Finally got around to winding some more of the toroids on my #QDX build...low pass filter toroids finally in ~3 years later (bought this at Dayton 2022...).
I can't find my solder and PCB vise after my move, so I've ordered some more and it should hopefully be coming tomorrow and I can spend my free time finally wrapping up a ton of the soldering projects I've got laying around.
-
Finally got around to winding some more of the toroids on my #QDX build...low pass filter toroids finally in ~3 years later (bought this at Dayton 2022...).
I can't find my solder and PCB vise after my move, so I've ordered some more and it should hopefully be coming tomorrow and I can spend my free time finally wrapping up a ton of the soldering projects I've got laying around.
-
An Early Bird #solarstorm Daily Double #POTA #parksontheair activation with some #FT8 using the @qrplabs #QDX & #QRPp CW #MorseCode with the #QCXMini 40m. Double Fun on Kentucky Oaks Day in Louisville, KY at US-7956 Beargrass Creek State Nature Preserve
-
An Early Bird #solarstorm Daily Double #POTA #parksontheair activation with some #FT8 using the @qrplabs #QDX & #QRPp CW #MorseCode with the #QCXMini 40m. Double Fun on Kentucky Oaks Day in Louisville, KY at US-7956 Beargrass Creek State Nature Preserve
-
I continue to regret the rookie mistake of applying 13.8V to my #QRPlabs #QDX digital mode transceiver. Due to shaky hands and needing to desolder a blown SMD driver IC, I got a repair estimate. Sliding scale $95 - $120 + parts & postage. Replacement cost, basically.
Don’t think I can go there so I will have to put this broken radio on the shelf until I have time to figure it out. Dang, it was a fun radio before I let the smoke out.
-
These ingredients produced a great #FT8 / CW #MorseCode #pota #Parksontheair meal on 40/20 meters. This activation was WELL DONE! @qrplabs #QDX #QCX #PutikeegMiniStraightkey #PutikeegKey #HamRadio
-
These ingredients produced a great #FT8 / CW #MorseCode #pota #Parksontheair meal on 40/20 meters. This activation was WELL DONE! @qrplabs #QDX #QCX #PutikeegMiniStraightkey #PutikeegKey #HamRadio
-
Today's ingredients for a #POTA #parksontheair #FT4 #FT8 CW #MorseCode recipe. Looks like the oven might be overheating a little. Doesn't matter. We'll finish with a yummy and tasty morning activation. #AmateurRadio #Hamradio @qrplabs #QDX #QCX @panasonic #Toughpad
-
Today's ingredients for a #POTA #parksontheair #FT4 #FT8 CW #MorseCode recipe. Looks like the oven might be overheating a little. Doesn't matter. We'll finish with a yummy and tasty morning activation. #AmateurRadio #Hamradio @qrplabs #QDX #QCX @panasonic #Toughpad
-
I spent at least 6 hours researching 9v capable power supplies/options for my incoming QRP Labs #QDX digital transceiver and then I just punted and got an adjustable bench supply.
Do your power supplies just keep multiplying the longer you're into #HamRadio? Every device with its own dedicated supply? Some things running off batteries? I feel like I need a strategy here lol.
-
I did my first POTA attempt today, activating Vondelpark in Amsterdam (NL-0166). The batteries for both my radio and laptop lasted longer than me in the quite chilly park. I got 13 QSOs on FT8, using a QDX and a telescoping vertical antenna. I was hoping to find a picnic table, but had to make do with just a bench. Lots of people in the park, two passers-by were curious about the antenna.
-
I did my first POTA attempt today, activating Vondelpark in Amsterdam (NL-0166). The batteries for both my radio and laptop lasted longer than me in the quite chilly park. I got 13 QSOs on FT8, using a QDX and a telescoping vertical antenna. I was hoping to find a picnic table, but had to make do with just a bench. Lots of people in the park, two passers-by were curious about the antenna.
-
I had my first QSOs with the #QDX radio yesterday!
Turkey, Germany, Italy, Hungary, Croatia on #ft8 from Finland. 5W feels like a lot more than the 1W I had previously with a Softrock. Something is still off in the receiver though. No image rejection according to the built-in tests, and strong noise in the RX audio below ~200Hz. -
I had my first QSOs with the #QDX radio yesterday!
Turkey, Germany, Italy, Hungary, Croatia on #ft8 from Finland. 5W feels like a lot more than the 1W I had previously with a Softrock. Something is still off in the receiver though. No image rejection according to the built-in tests, and strong noise in the RX audio below ~200Hz. -
After Doctor's appt always means #hamradio #amateurradio #pota #parksontheair #ft8 activation with compact @qrplabs #qdx and #panasonic #toughpad
-
After Doctor's appt always means #hamradio #amateurradio #pota #parksontheair #ft8 activation with compact @qrplabs #qdx and #panasonic #toughpad
-
More experimenting with the QDX:
I told WSJT-X to listen for FST4W on 600m, and it works.
Decoded a few stations!
Just RX only, since I can't tune the antenna for those bands, and I have no idea if the QDX would want to TX on those bands safely.
-
JS8 on QDX works better with autotuner and big Butternut vertical on roof.
And without desktop computer that forgets USB soundcard on every TX.
And without rig control having hamlib knocked over by RF into serial cables on transmit.
And, oh yeah, not on a system without ntpd, so I was calling out of sync with everyone's listen cycle, 'cause my clock was off.
-
JS8 on QDX works better with autotuner and big Butternut vertical on roof.
And without desktop computer that forgets USB soundcard on every TX.
And without rig control having hamlib knocked over by RF into serial cables on transmit.
And, oh yeah, not on a system without ntpd, so I was calling out of sync with everyone's listen cycle, 'cause my clock was off.
-
I have been running the QDX with a 9V power supply for testing.
Tonight I bumped up to a 12V power supply, retuned the portable vertical antenna on 40m with the Nano-VNA, and sent out some heartbeat packets.
On pskreporter.info, those packets got reported from receivers along the west coast of America, so I'm getting out.
More testing!
-
-
More QDX toroids wound last night with 0.33mm enameled wire, an oddly soothing activity.
Glasses off, myopically checking and counting turns of wire up close, before soldering them to the board.
If I can get this QRP digital radio assembled and tested today, perhaps I can use the 20m-40m magnetic loop antenna to have a listen and maybe squeak out a 4W WSPR signal as a test.
-
Noticed that Hamvention created a lot of buzz about Josh #N5FY & @Tuftelndotnet For 2 years, I've used his 40/20 Linked EFHW specifically for my @qrplabs #QCXMini & #QDX. This combination has garnered hundreds of QSOs. This is just one of Josh's products I use. I have nothing but praise for his quality products.
-
The @Tuftelndotnet #tufteln #kneeboard is not only great for a #QRP #QRPRADIO but also a perfect fit for my @qrplabs #QDX & #panasonic #toughpad for #FT8 #parksontheair #POTA work
