Beiträge von Remco

    Early this morning the two EB's were present here.

    However, when I looked at my screen at 09.30z the

    beacons were absent. Turning the dish didn't help.


    I'm still able to RX other beacons from other satellites.

    Yes, you can be fooled easily. What I always do to confirm the identity is turn the dish and look for another satellite beacon in the same frequency range.


    In this experiment: 11200.6H 21.6E, 11200.8H 16E and 11200.0H 7E.
    While you turn you see the beacons appear en disappear perfectly.


    When I made SNG (Satellite News Gathering) uplinks ca. 20 years ago, this was
    a perfect procedure to double check you had the right satellite.

    For use on 2,4GHz maybe the anaren filters are better removed?

    Yes, that is what I did (this are not filters, but circulators), and moved one trimmer somewhat.

    (don't look at the blue module, the plastic was heated (too) much (with hot air) during an experiment to ascertain if removing the output trimmer of the blue module yielded some gain. It didn't . . . The pallet still works)

    DB8TF : I have also a larger version of this pallet. Delivering >60W O/P with the same drive (3 mW). Friends of mine tested these at 2320 (and I believe one of them (also) at 2400) MHz, and were satisfied.
    I haven't tested this version myself (yet).


    Edit: I just verified. One friend gets >50W O/P on 2400 MHz with the pallet above.

    I use this kind of surplus pallets. Around 3 mW in and (measured) around 30W @2.2, 20W @2.3 and with some tweaking 11W @2.4 GHz output.


    Overall efficiency @2.4 GHz is not very good, but what the heck . . . for 10 Euros (!)

    Today I succesfully received two beacons from Es'hail-2. Using Astra-2C @10951.5 MHz as 'starting reference' it's already possible to see/hear the beacons indoors with a 70cm offset dish through double paned windows.


    To verify I was not listening to birdies I checked other beacons from other satellites. The Es'hail-2 beacons are relatively strong and 11205 is somewhat stronger here than 10706 MHz.

    A (very) good crystal ('especially cut for you') has a precision in the range of
    0.5 ppm (variation in temperature(s) not included).

    So, for these PLL-LNB's with a crystal of (mostly) either 25 or 27 MHz, let's take

    26 MHz as mean frequency, the frequency will be off (in worst case)
    0.5 * 26 --> +/- 13 Hz (a range of 26 Hz)

    The LNB 1st LO is (often) 9750 MHz, divided by 26 MHz = 375 * 13 = +/- 4.875,

    say ... +/- 5 kHz off and/or 'wobbly' in worst cases (over time).


    So, my opinion is that a single crystal will not be sufficient for narrow band
    operation. (Your .. all .. mileage(s) may (of course) vary)

    Peter, an alternative could be to mill off the horn part of
    the LNB and use 24/22 Ms or Cu pipe/tube in conjunction
    with your patch feed.

    Thus omitting the SMA-connector and bottom plate in your
    current 10 GHz-contraption.

    Knowing (at least) two other (Dutch) initiatives for an

    Es'hail-2 SDR-Web-RX (commonly known as 'WebSDR'

    (c ) PA3FWM) -and being involved in one of them-

    I am not the person who speaks in terms of 'good'

    (and/or 'bad').

    Framing and bashing that 'simplex operation' is 'bad' is as evil

    as framing that 'duplex operation' is 'good '.


    I prefer to speak in terms of 'different perspectives (and/or

    opinions)' and explore these opinions with respect, instead

    of bashing/judging a priori.

    Rob, since 30 yrs we are not friends. Reading your (written)
    words, I think this forum is not the place to 'grab your point of view' and
    'bash' me. I have another perspective: agree to disagree
    (and hope you agree with that).

    Let's wait until the satellite is launched and the amateur payload is up
    and running . . .
     



    It won't suprise you that I disagree.


    Once the power of the ground station is adjusted
    properly (i.e. below level of the LEILA2-jammer)
    there is no need for monitoring your uplink signal constantly.

    Experiment with GPS locked 27 MHz PLL LNB.
    Listening to the 11th harmonic (produced by a diode)
    of 953.6 MHz (generated by a GPS-locked signal generator).

    Click here for a short movie.

    Loopfilter was calculated with AdiSimPLL after I determined
    the Kv of my VCXO (4.36 kHz/V). Loopfilter BW = 300 Hz.