Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- QRPLabs
- Messages
Search
Re: rxerror.html
¿ªÔÆÌåÓýJohn,It's only in the alpha builds. . You'll have to compile it yourself. To do that for any of the flxxx apps go here and follow the instructions carefully and it works 100%. Once it's setup it's very simple to do again. 73,
Cliff, AE5ZA
|
Re: Multiple U4Bs to Track
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 |
Re: QDX FLrig JS8Call Pi4
Michael Black
Don't know why you would need a samba server.... What OS are you on?? What is pphAdmin? Mike W9MDB
On Monday, January 30, 2023 at 03:55:39 PM CST, John via groups.io <n0ure@...> wrote:
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 |
Re: Bifilar - Trifler transformer function in Amplification
#5wPA
Timo, It all depends on how the tri-filar is connected. It's just three parallel?windings on a toroid. You could connect all three is series, tap one of the common points and get 9:1 or, you could tie two in series and leave the other separate and have two 1:1 with 180 degree phase difference or 4:1 with a center tap on the hi-z end.... Just about anything you want to do with it. So in the series connected try-filar, or the bi-filar windings case ike your example, it acts as an autotransformer. A single winding transformer. If you tap it half way it is technically the?same as a 2:1 turns ratio (4:1 impedance) conventional transformer. Tap it one third of the way and its a 3:1 turns ratio (9:1 impedance). 73 ¡ Ron On Mon, Jan 30, 2023 at 1:26 PM <timo.vandermerwe@...> wrote: Thx Ron, |
Re: QDX build option- hybrid lo & hi version?
#qdx
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 |
Re: Bifilar - Trifler transformer function in Amplification
#5wPA
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 |
Re: QDX build option- hybrid lo & hi version?
#qdx
Hi Stu 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 ? ? |
Re: Bifilar - Trifler transformer function in Amplification
#5wPA
Hi Tim. In this case it is providing?a 1:4 impedance step up from the 12.5 ohm FET Drain to 50 ohms at the input of the low pass filter. Ron On Mon, Jan 30, 2023 at 1:07 PM <timo.vandermerwe@...> wrote:
|
Re: Bifilar - Trifler transformer function in Amplification
#5wPA
Thx Dave and Paul, Looking at the snip I agree that the bifilar winding 1 connects the 12v supply to the drain of the mosfet.? Winding 1 then connects to Winding 2 to provide the PA output.? Sorry for this uneducated question, but what function does the transformer perform in this instance.? ?? 73 Timo zr6tm |
QDX FLrig JS8Call Pi4
I'm not having good luck putting all four into a working chain.?
With the QDX USB attached to the Pi I see a serial QDX port with the Config | Setup | Other tabs. I press the 'init' but I do not see any change in status or display options. Does anyone know what I am missing? When I bring up JS8Call and select radio flrig flrig I see HAMlib errors. Much more to learn. John |
Re: QCX+ 20m Receiver sensitivity way down
#20m
#problem
#troubleshoot
g4edg
Hi Bryan
I had a similar thing happen on a QCX mini, the culprit was a burned up Q5...a BS170... Strangely this started as a reduction in TX power, Q5, shunting the output to ground partially until it fully burnt out whereupon the TX output returned to normal along with a very signal deprived and deaf RX. Good luck in tracking it down 73 Steve G4EDG? |
QDX build option- hybrid lo & hi version?
#qdx
Greetings all. I finally ordered my first kit (QDX) from Hans. Something I should have done a couple years ago had I not had a silly confusion about the nature of MFSK in general, Olivia (my favorite mode) in particular. I've been inactive for a decade & ready to start back in.?
Question- Is it reasonably possible to substitute a band or two from the hi band parts kit into a low band kit? Or is there more to it than just swapping out filter parts? Would the software be adaptable by user to reflect the correct band & band limits?? Might not be worth my effort if it requires much engineering know-how. I believe my assembly skills are up for the build, but my radio theory knowledge is admittedly weak. Han's instructions look excellent, just my speed! Looking forward to the process regardless.? -- de Stu AI7AN |
Re: Bifilar - Trifler transformer function in Amplification
#5wPA
I presume, because your question is not sufficiently clear, that you are talking about a push pull amplifier, where a bifilar or two winding transformer is connected between the FET Drains and the power supply.? Sometimes there is a third winding that serves as the output winding.? Sometimes there is a separate transformer for the output impedance matching. The Bifilar Transformer serves to bring DC power to the drains and is a Push Pull transformer.? One side will be going positive while th either side is pulled to ground by a conducting MOSFET. That make sense? Dave On Mon, Jan 30, 2023 at 1:54 AM <timo.vandermerwe@...> wrote: Dear all, |
Re: Bifilar - Trifler transformer function in Amplification
#5wPA
¿ªÔÆÌåÓýIMHO, the reason for trifilar is for tight coupling and balance between the windings. For when "close" isn't good enough! ;-) Paul On 1/29/23 22:54,
timo.vandermerwe@... wrote:
Dear all, |
Re: DIY enamel scraper: modified seam ripper
I live my Knipex stripping tweezers, you can get up close to the toroid without nicking it or the other windings.?
Those tweezers come with 0.6mm jaws standard; there are also 0.5, 0.8 and 1.0mm replacement jaws available, per this document.??? Does anybody here remember Strip-X (Stripex?) that foul-smelling chemical wire stripper?? Dip the wire into the concoction, wait a few seconds and wipe with a paper tower.? Contained phenol and other nasty stuff.?? 73, Don N2VGU |
to navigate to use esc to dismiss