Homemade 2.4 GHz RF Amplifier - Testing ON AIR

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  • Опубліковано 23 лис 2024

КОМЕНТАРІ • 23

  • @FesZElectronics
    @FesZElectronics 9 місяців тому +5

    Did you try measuring the RF coming out trough the various non-RF wires? (like the power cable, thermal monitoring); I noticed that the wires just pass trough the enclosure, without any other measure applied - I may have missed something of course; the point that I am trying to make is that any conductor that passes trough the case which is not locally grounded will carry the RF signal - it is common to use dedicated pass trough's that provide capacitance to the case to shunt any high frequency noise.

  • @j3xk72r9
    @j3xk72r9 Рік тому +3

    I think you might need to add some heat sinking to that isolator. As it stands, it would probably get very warm if a significant proportion of your output power ever came back down to it. Why not try to thermally couple it into that big blown heatsink?

  • @MrDmjay
    @MrDmjay Рік тому +2

    Nice engineering mate.
    Good work.

  • @dxscotland5901
    @dxscotland5901 Рік тому +2

    Great setup Matt!

  • @ingmarm8858
    @ingmarm8858 Рік тому +3

    G'day, interesting build. You showed us the 10GHz out of the satellite to show you have no out of band radiation but you didn't show us the harmonics you may be generating on 4.8/7.2GHz etc. Do you have some spectrum analyser shots of that to give us an idea of the spectral purity of the amp? Cheers.

  • @bob_mosavo
    @bob_mosavo Рік тому +1

    Awesome ‼
    Thanks, Matt 👍

  • @loueckert4970
    @loueckert4970 10 місяців тому +1

    Wow that's quite a powerful amp at these frequencies, considering the gain available in a small dish. Good job. 73 de KT1R

  • @HighlanderMcLeod
    @HighlanderMcLeod Рік тому +3

    Oh! Great, I was just interested in such amplifiers. However, I have a different range - HF

  • @Trent28888
    @Trent28888 Рік тому

    The circulator looks good but that needs to be directly off the PA as it needs to be mounted to the heatsink but I cant work out why ya didnt put any TX/RX relay and a sequencer in the case cause u will need it

    • @TechMindsOfficial
      @TechMindsOfficial  Рік тому +1

      It’s an inline coaxial isolator, by design, so it’s perfectly okay where it is. I don’t need a tx/rx relay because with my setup I am receiving on 10GHz via an LNB and transmitting on 2.4GHz with a patch antenna. Thanks for your comment, appreciate the questions. Thanks 🙏

    • @mikewillis1592
      @mikewillis1592 Рік тому +3

      @@TechMindsOfficial Actually Trent has a good point. If significant power is reflected from the feed then that power is absorbed in the terminator for the circulator. If you have a good match, that's not much power. It is when there is a fault that you need the protection and potentially all the power ends up in that circulator termination. The PA still sees a good match and sends its full power. If that power it isn't being absorbed by the antenna, where is it going to go? The answer is of course into that termination, so, heatsink it.

    • @TechMindsOfficial
      @TechMindsOfficial  Рік тому +1

      @@mikewillis1592 Hey Mike, The termination on the isolator is rated at 100 Watts, I believe, and it already has a block of metal to sink the heat into. For my "use case" this amp will only be used on DATV, and something which is always in front of me when I transmit is my received downlink signal strength. As the amp doesn't alter its own power output, and I normally run around 60 Watts Max, If there is an issue I will be able to disconnect power to the amp immediately without the isolator even getting to its maximum rating. If I was always going to be running with a bad match, which I guess some people do, then of course, I would look to do something about cooling it further, but at the moment its well within spec for my use 🙂

    • @mikewillis1592
      @mikewillis1592 Рік тому +1

      @@TechMindsOfficial That's the point. If the match is good, no issue, if not up to 60W gets dissipated in the termination. Then it will need to be heat sunk if the fault lasts for more than a few seconds, unless you detect the situation and turn it off. Most people don't use isolators. Several are now looking for replacement PA transistors (:

    • @roba2440
      @roba2440 Рік тому

      You can get temperature operated switches - you could stick one on the isolator heat sink and put it in line with your 28v enable signal. Just monitor the temp in normal operation to choose a good temperature to open the switch at. No software, so reasonably reliable.

  • @che59v
    @che59v Рік тому +1

    Great video and great technology BUT!!!
    One of those frequencies I personally ( ex radar worker ) won't amplify to more than a few milliwatts at best (in a home setting). The fact that technology allows us to do it does not mean we should be doing that (again, in a home set up), stay safe, and avoid those Frequencies ( in high power). 250mw radiated AWAY from your property should be the max around your home and family, why? cancer is not your mate, the gear to measure this kind of unwanted radiation on this spectrum of the RF band (RF leaks/reflections ) are limited and expensive, its a hobby, doing the wrong thing here might limit your play time in the long run. never underestimate the high frequency spectrum, some frequencies are best left alone (again, in a home setting).
    No tin foil hat around here, 2.4Ghz is a great band to play with when used with low power applications it will not be something to worry about. Using 1 Watt at 1m from an omnidirectional antenna, at 2.4GHz, that signal has dropped by 40dB, which has you at .01 milliwatts, or 10 microwatts, now compare that with 900MHz (same condition as above) will be dropped by 30dB, which is 100 microwatts., when using higher power setting things will become ugly very quickly.

    • @namregpxp
      @namregpxp Рік тому +2

      I am really interested if microwave frequencies can cause cancer. Can you provide some study or reference material in the subject for me to read.

    • @ingmarm8858
      @ingmarm8858 Рік тому +4

      In the case of this video the op appears to have multiple devices capable of detecting leaks at and in excess of his operating frequency as well as a technical awareness and no doubt in the UK like here in AU, an obligation under his license conditions to limit radiation hazards around his station. With a limit (in Australia) of 4W EIRP for Wifi on 2.4GHz it would be impossible to meet your exposure ideals unless you live on a dessert island! My professional life revolves around sniffing around the RF spectrum using "all the $$$ toys" so to speak so I'm well placed to observe the levels of RF exposure we all experience in everyday life. Probably also why I laugh very loudly at every 5G mind-control / nano particle / nutter video clip on social media..

    • @che59v
      @che59v Рік тому +1

      @@ingmarm8858 technical awareness is key 100% agreed. The last thing we all need is more regulation and fear, what I see missing in the hobby is awareness with regards to this spectrum ( seen this over and over again), I tend to agree that some videos about 5G being a "mind-control" band are laughable ( some are just sad) and serve to make those who seek real answers even more confused.
      All I can say those to those who want to get involved on 2.4G and above, GREAT , lots of fun indeed, but If you know nothing about this spectrum and have no past experience it would be wise to seek the help and the knowledge of those who have some experience, play it safe, and enjoy the hobby.

    • @che59v
      @che59v Рік тому +1

      @@namregpxp Do a search, there are so many videos and articles that show the good, the bad and the ugly, don't let fear stop you and gain the knowledge needed, ask around for those hams who are in the game already as their experience will save you time and mistakes.
      Good luck.

    • @robertvandersanden
      @robertvandersanden Рік тому

      In this respect I see several DC wires (supply, fan, temp sensor) going through the wall of the box without and feed-through caps or filtering. These wires may pick up radiation inside the box and radiate it outside the box. Don’t know if in health threatening levels but the shielding of the box is certainly compromised.

  • @howtobob2749
    @howtobob2749 Рік тому +1

    Nice job, 73 de Iu3qph Bob