Hi Terry, ?Thanks for the great feedback!

I'll change the BS170s. ?Should I in fact change all four at once or can I mitigate potential rework damage and simply change one at a time and test? Or will this present a potential electrical imbalance of more than one BS170 is blown and risk additional circuit damage?

BS170 sockets sounds interesting but I'm sure that has its pros and cons including proper heat dissipation.

I ordered a couple of HiLetgo LM2596 adjustable DC-DC step down buck power convert module 4.0-40V input to 1.25-37V output with LED voltmeter display.

I do have a 23 year old Astron RS-35M linear power supply (dedicated to my IC-756Pro) sitting under my desk. ?I suppose that I could try that with a buck converter. ?I also have a junk box full of various leftover wall warts / adapters but I suspect that they're not "clean enough" for this application. ?I also have some larger (3.5" x 7.5") flat bricks leftover from old larger laptops that are rated at 19.5 VDC @ 12.3 A. I suspect that the filtering may be somewhat better on these. ?Thoughts?

I looked at the specs on the Alinco that you mentioned. ?That looks like a great supply and something nice to have! The ripple spec is <15mV p-p at rated load. ?I went looking for the ripple spec on the universal adapter that I mentioned in my previous post. ?There were no significant spec details on Amazon but one reviewer did say, "Extremely noisy output, A nice Fluke multimeter will show pretty constant output, but o-scope shows 3V+ AC of noise. 3V voltage swings of noise and ripple that seems to scale a little depending on which voltage state you select. Don't use with sensitive electronics!" ?Please understand that I didn't doubt you. ?I'm simply trying to get to root cause vs. apparent cause. ?I don't want to keep changing BS170s. ?The amazon review above does confirm your suspicion that the Universal PSU may be the problem (along with me pushing it too much with 9+ volts in).

Another temporary option I could try is the solder rework station that I recently purchased has a 0-15 VDC @ 3A supply but I'm not sure how "clean" that is either. ?I may just end up with the Alinco which I could use for other things. :-) ?I still need to build my QCX+ and the 50 watt amp.

Thanks again for the suggestions; they are really appreciated!

73, ?Peter ?W1DAD ?Windham NH

Hi Rick,

Those settings seem right to me. If you display the heartbeat signal on the LCD and you see it pulsing, I think you can be sure you are disciplining the frequency. This is the #HB special code which you would set on the display. Btw, the variable attenuator you clued me in on works very well with the SigGen.

73,
‘Gregg W7GRM

The QLG2 arrived today and it is now installed in the QRP-Labs SigGen. However, I am confused?

1) The GPS red, yellow and green (1pps) LEDs are functioning as they should.
2) GPS Mode is set to 2 9600
3) The TCXO is set to 25.000 MHz
4) GPS is connected to the SigGen with 5VDC, GND, DATA, 1 pps via a 4 conductor ribbon cable and appropriate Dupot connectors
5) Ref. Freq. indicates 25,000,000 Hz
6) The correct Maidenhead of CN88HL is displayed

Now for my questions:

1) I assume that the GPS Discipline process is automatic at turn on?
2) Have I missed any settings?
3) How can I determine if the SigGen is being Disciplined by the GPS?

Thanks,

--
73, Rick
VE7TK

Website:

Peter,

Been there-done that! - You popped one (or maybe two) of the BS170's - easy just to change all 4.

Some folks have even installed sockets for the BS170's - Like "Smarties" always keep a supply close by!

I will dig out some earlier posts for additional cooling (if you wish?) but I think your problem is the Universal PSU - not stabilised enough - over-voltage and/or maybe a voltage spike?

Look at (invest) in a different Power Source I use an "Alinco DM-330MV" for pretty much everything (with Buck-Convertors for different rigs) but you can also PU small LiPO batteries quite cheaply (and use a buick-convertor!)..
Another less expensive (low-noise PSU is made by "Pro-Audio Engineering", designed for the KX3, it will give you a useful PSU - but again, use a buck-convertor!

I'm sure others have favourite PSU's that will give you control over the VDC?

Good Luck!

73

Terry

Ron,
Thanks for your guidance. I'm glad you are here.

1.) Connections look good on T1.
2.) 10K resistors at R1 and R2? are marked accordingly. ( the radio has been working close to a year now so no surprise there)
3.) L3 solder joint however looked suspicious on the side opposite of C29 but pulled it scraped the wire and reinstalled.?
2.) Voltage on lifted wires 5 and 8 were at 2.484V each.
3.) DC continuity good between Center BNC to L3 C29 side. (before and after L3 connection improvements)

I see no evidence of smoke or arching anywhere.??Attempted the alignment again (prior to lifting T1 5&8) and still no luv. Amplitude on Peak BPF is not above 3. I recall much higher values on initial alignment. The IQ Bal, Phase Low and high are not very responsive and trimmers are ending up at at component limits evident by the light clicking at end of travel.

Thanks again for your guidance.
--
regards,
Bryan, N0LUF

OK. Figured it out. Going through the menus I noticed that the Ref Freq was reset to 27 MHz with the new update chip. I installed a TCXO some time ago, so upon changing the freq to 25 MHz, SWRs went back to normal. 73, Mitch NK3H?

Well, I guess I spoke too soon! ?VE3EGA, so much for maintaining status quo... (and you should buy a lottery ticket - you called it...)

Since repairing my QDX 24 hours ago (and making 20 FT-8 contacts on 80m - 20m over a few operating periods totaling about 3 total hours powered on and now utilizing the EMTECH ZM-2), my output power has dropped considerably as follows:

80m has gone from 4.7 watts to 1.8 watts
40m has gone from 4.9 watts to 1.5 watts
30m has gone from 4.1 watts to 1.7 watts
20m has gone from 4.8 watts to 1.4 watts

My measured voltage input is 9.16 volts DC utilizing a SoulBay 3V/4.5V/6V/7.5V/9V/12V Universal adapter rated at 2.0 A max.

The case had been getting pretty warm and I was about to take the suggestion above and measure the output with the adapter set to 7.5 VDC.

I've looked at Hans' troubleshooting guide and I believe that many of the "fixes" don't apply since I've made close to 400 contacts with this QDX and it had been working fine (likely not built wrong).

I've opened it up an reinspected it and nothing pops out at me. ?The search continues... ? ?ANY SUGGESTIONS?

73, ?Peter Schipelliti ?W1DAD Windham NH

I am using a Orange PI 800 which is a Chinese clone of the Raspberry PI 400 with the QDX.? The Raspberry PI 400 was not available to me.?? I followed the instructions in QDX manual and the work fine for JS8call.? In fact, I used the instructions for two other computers (old ASUS laptop, Raspberry Pi 3B+) and two different operating systems without any problems.?? I did encounter one problem with the brltty service.? But I did solve it,? I did post a message on this board, QDX with Linux with the solution. ?

John, you may need to learn about the package management system for the Raspberrian operating system.? The package management should be "apt".?? A search of the Internet, will turn up several good tutorials.? I found the terminal command "apt show package name (e.g. wsjtx or js8call)? shows what is going to be installed.

Sometimes, a library needed for the application is not installed.? I installed WSJTX first because I know it comes with HamLib.? I installed JS8call next.? I set up WSJTX using the QDX manual instructions then JS8call without a problem.? The QDX? with the Orange PI 900 combination has been working well.??? I hope this is a help.?

I think I'm missing something. This behavior is so bizarre: Purchased 1.09a chip from Hans and inserted into 40m mini. 5 watts out with 1.0:1 SWR into a dummy load. All good! Then tested on my dipole that has 1.2:1 SWR @7.020 MHz: 5 watts output, SWR 5.0:1. Replaced update chip with original Firmware 1.07 chip: 5 watts out with 1.2:1 SWR. Does a firmware upgrade require going through the setup/adjustment process in the assembly guide? Thanks for any help on this. 73, Mitch NK3H

开云体育

John,

Hi Joe
How many balloons do you intend to launch at the same time with the same call sign.?
Technically it is possible with the QRP-LABS tracking website, as long as the channel number is different, on each flight, and it would be better if there was no overlap or similar numbers on the telemetry ( 0x4xxx) timing.
That being said, Wsprnet maps probably would be confused and look odd with a number of tx sources and lines coming from the same callsign in different locations all over the world. And in practice ham radio operators do not usually transmit with the same callsign from different locations at the same time.
QRP-Labs tracking is supposed to filter for frequency and the timing of the Wspr and telemetry transmission and so all the balloons with the same callsign, should all be separated in tracking.? Other tracking websites may not filter for all these variables in the same way.
As far as I know, this venture with many balloons with the same unique callsign has not been tested extensively on the QRPLABS tracking website
You might not want to fly the same callsign , launch the balloons, and find there are data collisions. Definitely it would be a good idea to test all your radios on the ground at the same time and see what happens. I personally have 3 callsigns for multiple balloon events. The safest way, and what I would suggest for the moment, is to borrow a callsign from Ham friends and fly different callsigns on each balloon.
There may be another possible way of tracking... Tom W5KUB is showing a number of different flights on Sondehub but there is only one instance W5KUB on the Wspr website.? Perhaps Tom will chime in on this one.
Dave VE3KCL

I think I found the way out.
I went back to FLrig and selected QCH+. It activated. I then went to JS8Call and there is a QCX/QDX radio type.
AND CAT IS GREEN!
Now I need to read the book.
All is well.
J

I have fallen down the rabbit hole. I installed HAMlib and I do indeed see a QCX/QDX radio type,
but to install that radio selection I need to use pphAdmin. To install this utility I need to install a SAMBA server!!
way too much ! I must be in the wrong place.

LostJohn

Thank you, Muhsin. I had wondered what I was missing. This gives me something to look at and consider. Always interested in learning, though I'd be apprehensive about not having the LPF's. I may be more open to that level of adventure if I can aquire more test equipment before I retire in a very few years.?
--
de Stu AI7AN

Is there somewhere I can find the mods, and fixes for rev 3 in one place? or at least a list of them that I can research..
I'll also need same for some rev 1's

thanks
73
Vince
N2AIE

Thx Ron,
Makes sense and is what I expected.? So if bifilar provides a 1:4 impedance step, what would trifilar in the same configuration provide as a impedance step?
73
Timo
zr6tm

Hi Stu
QDX has

4 BPFs in the front end (selection of the toroid here might be tricky, 37-2 or 37-6)

3 LPFs after the PA output

please study the manual for normal and hi-band

you'll figure out

I did some experiment with an LPFless QDX

it is possible...

73 muhsin TA1MHS

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