Posts by I0LYL

    Sorry Dear Lucio, I don't want to cause more headache on you, keep calm.

    ...

    I want to emphasis that I would say exactly the same if it would have been a German company violating the rules, no doubt..

    ...

    73s Peter

    Hi Peter, he never had the slightest doubt about this and your good faith. I cannot say the same for other subjects who raise the red-blue pencil only when it concerns the behavior of others.

    For the rest I endorse everything you said about it and thank you for doing it.

    Let me clarify that with D-Orbit I have nothing to do except the national flag which has certainly influenced my reaction.

    For the rest, this is their answer and some further information on this mission.



    Hi Peter, I had premised that when I talk about these things I get a headache. Certainly "D-Orbit, is an commercial satellite (platform) that carries 12 commercial CubeSat's from Planet to be deliver to orbit by them." But D-Orbit is not the only company that operates in this way and above all it is not the first. Even NASA and ESA have put satellites into orbit using amateur radio frequencies. The same universities that put microsatellites into orbit often buy them as kits from commercial companies. Universities often work closely with commercial companies. You will remember that even Pacsats were sold in some form of Kit. The boundary is blurred, sometimes it is difficult to separate the didactic purpose from the commercial activities. Then, what I am trying to say is none other than what IARU itself claims.

    I transcribe faithfully ... copy and paste.

    "Ultimately, the decision of whether the proposed operation is appropriate for the amateur-satellite service rests with your country's administration (your national telecommunication regulator). Therefore, before sending your frequency coordination request to IARU, we suggest that you consult with your administration to determine whether the amateur-satellite service or another radiocommunication service is appropriate for your operation. "

    What I meant in the previous message is this:

    The radio spectrum, the distribution of frequencies is the exclusive responsibility of the individual states. We may like it or not and we Italians are not particularly happy with this but ...

    This is the official situation in Italy. It is written in Italian but it should be understood. Where there are only radio amateurs that portion of the spectrum is in exclusive use. Where there are other items in the single portion then we are in cohabitation with other services.

    It is not the IARU or the single IARU delegate that can change these facts, therefore their refusal, however granted to others, is (in my opinion) devoid of any value.

    Be patient but when it comes to bureaucracy regarding our amateur radio activity, I get a headache.

    What does this stuff mean here?

    "The IARU will only coordinate a non-amateur satellite if an administration directs in writing that it be operated in an amateur-satellite band under an experimental or other non-amateur license."


    P.S:

    Between us ... for me "Satellites for which Frequency Coordination has been declined" is nonsense. Coordination is necessary to avoid interference and to have a certain and known contact person who can be contacted immediately in case of interference with other services.

    Coordination is in no case a license that can be granted or refused. Authorizations and licenses are issued by the public administrations of the respective countries.

    If we then look at how many satellites have been granted coordination and which have been refused, the matter becomes more complicated. A never personal estimate leads me to consider that a percentage of 5% of nano-pico satellites are truly amateur. The remaining 95% of these microsatellites have nothing to do with radio amateurs and have also been coordinated.

    If I'm wrong, correct me, insult me as well, but let's not hide behind a finger.


    Hi Peter,

    from what I see the problem of the WB Beacon is solved for the moment. The problem regarding PCR Accuracy Error remains but this does not seem to affect the correct reception of the beacon.

    The most serious error, in my opinion, concerns the accumulating timing errors but this is overcome by the reset programmed every 24 hours.

    Given the conditions, I think the maximum possible has been done ... as always.

    The problem that seemed solved has come back. The WB Beacon is not working properly and it is impossible to receive it correctly.

    It is as if, somehow, the scheduled reset every 24 hours is not working properly.

    With my modest home instruments I see the following errors that do not allow to receive the WB Beacon correctly.


    error 1.4: Continuity_count_error


    error 2.3: PCR_error


    error 2.4: PCR_accuracy_error


    error 3.3: Buffer_error


    Maybe a manual reset could help you buy time?

    hi Joseph,

    welcome to this forum. If I can give you some advice at the beginning you have to do everything with manual control. You will need to manually control the antennas, TX tuning, RX tuning, then manipulate the key or microphone. Check the doppler. All manually and only in this way will you be able to understand all the problems that you will have to face later with the automations. In a way it's like learning to fly a plane. First you learn to fly on sight and then you move on to instrumental flight. This is my humble advice.

    have fun.

    A clone of Adalm-Pluto has appeared on the usual Chinese e-commerce sites. The price is interesting (128-138 Euro free shipping), aluminum case, it seems smaller than the original, and in the characteristics it seems to already have the TCXO with greater stability. No product reviews, little technical information and someone will have to be the guinea pig sooner or later.

    On the other hand, they advertise with the excellent SATSAGEN program as well as all the other SDR programs.

    Anyone have more accurate news?


    This topic has already been dealt with in the past.

    It's like comparing the S-meter of different devices. A different program setting returns a different SNR value.

    I think it is more useful to look at the transponder noise floor, the transponder bell on the receiver noise. A value of 5 dB for a one meter dish is a good reference. More or less these are absolute values.

    I suspect your NanoVNA is not calibrated within the NanoVNA Saver program.

    In the program there is an assisted calibration function (Calibration/Calibration Assistant) and you have to activate it with the same cables that you will then use for the measurement on the antenna.

    @DO1OHB

    Yes, it works well with NanoVNA Saver 0.37 vers. x64 just tested.


    @G0MJW

    This one I just got is Ver. 2.2 with 4 inch screen and metal case.


    In the meantime I opened it to see how it is done inside ... it was born inside with SMA connectors apparently but then during the boxing phase they decided to put the N connectors. I'm doing the first measurements and it seems to work well at 2.4 GHz.

    I also have a whole series of SMA kits but I must say that the solution with N connectors seems to me mechanically more robust.



    My third NanoVNA has just arrived

    I espoused a philosophy of good tools at affordable prices and this is my third NanoVNA.

    4 inch display SAA-2N. This version has the N connectors, metal case, N-type calibration kit, two cables, a carrying bag, an N female-female adapter, a USB / MicroUSB cable, plus a free gift as an old buyer ...: )


    Basic performance:

    Frequency range: 50kHz - 3GHz

    Frequency tolerance: <2ppm

    Frequency Stability: <0.5ppm

    System dynamic range (calibrated): 70dB (up to 1.5GHz), 60dB (up to 3GHz)

    S11 noise floor (calibrated): -50dB (up to 1.5GHz), -40dB (up to 3GHz)

    Sweep rate: 100 points / s

    Display: 3.95 inch, 320 x 480

    USB interface: Micro USB

    Power: USB, Maximum charge current 1A

    Battery: 3000mAh lithium-ion

    Battery connector: JST-XH 2.54mm

    Maximum sweep points (on device): 201

    Maximum sweep points (USB): 1024

    Port 2 return loss (1.5GHz): 20dB typ

    Port 2 return loss (3GHz): 13dB min

    VNA-QT software supported platforms: Linux, Windows (7+), Mac OS planned


    Some photos and comparison with previous versions of NanoVNA:

    ...

    Last month we had already planned a Firmware update, which uses a watchdog to restart the hardware every 24 hours. This should then eliminate or reduce the accumulating timing errors.

    ...


    73s Peter DB2OS, AMSAT-DL QO-100 Team


    Hi Peter,

    from what I see the problem of the WB Beacon is solved for the moment. The problem regarding PCR Accuracy Error remains but this does not seem to affect the correct reception of the beacon.

    The most serious error, in my opinion, concerns the accumulating timing errors but this is overcome by the reset programmed every 24 hours.

    Given the conditions, I think the maximum possible has been done ... as always.

    Summary

    • Minor Linux driver bug fixing see full log below
    • ADALM-PLUTO PlutoSDR Rev.C support
    • libiio version 0.21
    • Support for persistent ssh keys and passwd changes
    • Updates to the HTML device/legal information page
    • Linux version 4.19
    • Enable ext4 filesystem support

    By pure chance I found this UHF bandpass filter on the net and, given the price, I immediately bought it: € 8.99 including shipping costs (AmazonPrime) Nothing in particular, usually SAW filter in line with others of the same category in the same range of frequency. Definitely useful for those who need to drive an upconverter (70 / 13cm) for QO-100 with Adalm Pluto.

    From the same family and from the same seller there are other filters for other frequencies but unfortunately they are not available for quick shipment. What do we buy with 9 euros?


    pardon the question, but why do the two measurements differ so vastly? It is certainly fine for 2.4g but I don't understand the rest of the behaviour. Do you have pictures of the two setups?

    Achim, my suspicion is that the adapter "MACOM N-male-SMA-female" not present in the circuit during the calibration phase has distorted the measurements.

    Mike, DL1GNM will be able to clarify the matter better.