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Christopher Andrews VK4DL
Registrace 26. 10. 2007
Trying Linux with VirtualBox.
Installing VirtualBox to play around with linux.
If you get an error trying to boot the VM, you will need to enable virtualization in BIOS. Search for Intel VT-x or AMD SVM.
If you get an error trying to boot the VM, you will need to enable virtualization in BIOS. Search for Intel VT-x or AMD SVM.
zhlédnutí: 27
Video
1W Power RF Amplifier "InitialPA" Testing
zhlédnutí 99Před měsícem
Not as clean at 30dbm output but ok (-20dbc without filter). I'm targeting 20db gain, perfectly fine at 7Mhz but gone by 30Mhz. This is my first PCB and I made 3 mistakes, but nothing preventing me from using the amp.
Mosfet biasing, dynamic class A vs class AB
zhlédnutí 41Před měsícem
I have learned how to more effectively kill mosfets.
Manually matching a dodgy antenna with a NanoVNA.
zhlédnutí 737Před měsícem
NanoVNA is love, NanoVNA is life.
Testing an amplifier's bias. It fails.
zhlédnutí 108Před 2 měsíci
Testing an amplifier's bias. It fails.
Bad Apple on ZT-703S oscilloscope
zhlédnutí 136Před 2 měsíci
The frame rate isn't great on X-Y, pretty good on Y-T.
Modified MiniPA70
zhlédnutí 596Před 2 měsíci
Robert (VK4DE) unleashed this device upon me a while ago, I finally got around to firing it up, and in the end I reworked some of the amplifier to get it to behave. I fixed the horrible input matching to something reasonable (1.5:1 until 15m): - 16:1 input transformer changed for a 1.6:1 (5:4 turns). 4 turn winding has a centre tap for Vgs bias. - 150ohm gate resistor changed to 25ohms. - 220pF...
Baluns getting CANCELLED!
zhlédnutí 86Před 4 měsíci
Ramblings of why the EFHW "cross over" doesn't cancel.
Audio Oscilloscope
zhlédnutí 27Před 4 měsíci
Just having a play with rendering again, will speed up development of certain projects. The source was: czcams.com/video/2NWazG1T7ps/video.html
Messing around with the NanoVNA #2 - Coax edition
zhlédnutí 89Před 7 měsíci
Messing around with the NanoVNA #2 - Coax edition
Messing around with the NanoVNA
zhlédnutí 491Před 7 měsíci
RigExpert users rekt. I also say "capacitive inductance" instead of "capacitive reactance" a lot.
First 2m & satellite (ISS) contact with VK4GAT
zhlédnutí 52Před rokem
First 2m & satellite (ISS) contact with VK4GAT
Messing around with baluns 1:1, 4:1, 25:1.
zhlédnutí 74Před rokem
Messing around with baluns 1:1, 4:1, 25:1.
Working FreeDV remotely on a Banana Pi M5
zhlédnutí 75Před rokem
Working FreeDV remotely on a Banana Pi M5
More testing of the homebrew transmitter.
zhlédnutí 94Před rokem
More testing of the homebrew transmitter.
Can you try macOS is may look hard but yeah I try it I fail and the next day I succeed you should try
I'm aware of the audio/noise gate issue, I didn't pick it up until virtualbox was installed. Skip through as needed.
Nothing a D8 dozer and roundup wouldn't fix, to improve things.
vk4pmw here very cool
Nice video.. I want to get a second multimeter and have looked at the one you have there. Is that a good one or would you recommend a different model around the same price range? I like the display a lot. Thank you!
No idea what I just watched, but interesting to see the process anyway.
Love it mate
Help lol💀💀💀
Fascinating. Subscribed 😉
Aad Bpple
All you need now is a case!
How will I work on it if it's in a case? :)
@@godarklight Of course.. My Bad
Bias issue? Is the preceding stage doing the same thing?
Looks good Chris
Core harmonics matter
Nice work Chris 🍻
You can actually do it a lot better and improve a lot, sadly you are too ignorant to know this. Google it instead and do a proper job.
Talkalot do nothing
me when April 1, 2024
nice can use this for work! thanks!! great!
Looks like its time for Trump to make Equestria great again.
This is great!
Excellent! Thanks for taking the time to share the logic behind your settings.
thank you very helpful
this for hard component type...not easy to melt...😅 like cpu..strong mosfet...low temp melt good for smd..not fake...fake is mean we make solder tin with paper😅 or someting...
Bad Apple is to proving something is a display what Doom is to proving something is a computer.
I AM GOING INSANE MAKE IT STOP
why is this recommended to me... Bad apple is fire though
Lmao
Can you post a video of the original sound that is being played through the oscilloscope to play bad apple? I wonder how it would sound :] thank you
github.com/yeonzi/badappe_oscilloscope/releases :)
why is it upside down but it still bangs
It is an Australian scope...
Bad Apple works on literally anything
just realized that you inserted australia joke 💀
Nice, another one to the collection
Does this work on a Canadian oscilloscope?
No
na increible
Bad apple still lives ❤
Goddayum
My man turn your camera 180 degrees!
it's an Australian joke
@@nicepotato5755 It's actually not a joke - it's a technical limitation. I couldn't invert the signal in hardware, oscilloscopes have a shared ground. Could have done it in software though :)
@@godarklight wwooooooooww missed opportunity there!
That's pretty cool.
Wha? What is this
This shall explain it well: czcams.com/video/rtR63-ecUNo/video.html
Wea wena weon
17 hours ago, nice
I can’t really see the screen well🤔
Australian like from me
how did this get recoment to me? howdy mate
Db carrier supression? How much is normal ?
I mean if it's just for soldering automotive wires together the cheap stuff performs rather well as long you got a 60-100W Iron 🤷🏻♂️ but for circuit boards it's gonna be annoying
At 400c, the insulation would melt. It can be seen in the video it performed badly lumpy and costed considerably more effort and time. On circuit boards, it would destroy components.
FWIW I have found that the choke baluns wound with coax on those cores tend to have relatively narrow bandwidth, I think this is due to capacitance between turns, I have had better results using twisted pairs on them. Not a problem for the bands you are interested in but it still might be productive to use more turns of a smaller coax. The NanoVNA is a wonderful tool.
I sort-of tested the choking impedance just by wrapping a simple wire around the "FT240-43" 6 times, as that's all I could get with RG213 - it's just over 20db of suppression which seems to be enough. This antenna is mainly for 80/40m - I have a different one for 40-10. There is a suspicious dip right at the start just above 1mhz, that would be the choke failing to do anything down that low, but it doesn't need to work down there so I'm not terribly concerned about it. The advantage of this setup: Two less connections to make, and it doesn't get much cheaper. "Dirty baluns" without the toroid are completely useless with my testing.
@@godarklight, "dirty baluns" more normally known as ugly baluns often can make a situation worse, Although they can work the results are far from guaranteed. I suspect that in many cases 20dB of attenuation is adequate but a lot higher figure can be achieved on those cores. Like you I have done the simple tests with a single wire to get an idea of how the toroids perform but with aa fatter conductor (like the shield of 213) a lot of capacitance between the turns does affect the results. Not knocking your work, but have been messing with choke baluns a few years and have found them interesting to experiment with.
Impressive
I randomly looked at this video and found some comments. I do think this is probably lead-free solder, but I am fairly sure it was marketed as 60/40. This video has much better detail of fake solder, and definitely says 60/40 on the reel: czcams.com/video/5Ku7I3hA3AA/video.html
That's lead free. I had same problem with a small amount of 60/40 I bought for testing. The chinese market is badly contaminated and I would advice against buying chinese solder. The BEST brand is supposed to be good, but it isn't that much cheaper than local stuff. Then, there is the risk of fake on the chinese brand. We should all stop buying chinese solder and let those clowns go bankrupt.
that's too cool... those sproggies are probably overdriving. cus if you look they're not there with your drm transmission so it could actually be just something in the sound card.
Yeah it only happened when I cranked the volume, I think it's actually just the sound card clipping and not anything to do with the radio itself. I've made a bit more progress, the carrier is actually just the LO getting picked up by the SDR, I couple it via an attenuator in the latest test.