Posts by F1FCO

    Hello everyone,

    Has anyone had recent contact with Antonio, CT1FFU or with DXPatrol ?

    I ordered on 08/19/2021 an helix antenna and an LNB (and paid by PAYPAL) but I have no news

    I sent several messages, directly to Antonio and also on the DXPatrol site, but no response


    for ON4IQ, who seems to know DXPatrol well, is there an explanation?

    Thanks for your help

    73s from F1FCO, Pierre.

    hello,

    is there a possibility to solder a backup battery for the GPS receiver ?

    the datasheet for the NEO-7N-0 module says 3.6 V max and 15 µA flow in the absence of power

    so a lithium battery? or a CR2032 ?

    has anyone tried ?

    the GPS fix is verrrry long... (8-10 minutes)

    Coming back to the DX-Patrol ground station that I use outdoors, there is a small offset of about 200Hz between transmit and receive.

    I think this is due to the fact that we cannot get EXACTLY the correct frequency when receiving with the ADF4351.

    The OL in emission is on 1967.500: no problem to obtain this frequency.

    OL in reception must be on 1650.379487: impossible to program exactly on an ADF4351

    a solution for this Ground Station would be to use a reception module like on the Down Converter: LNB with output on 739.xxx

    OL must be on 9750 MHz (25 MHz internally x by 390) and OL of the converter must be on 307 MHz for an output on 432.xxx or 557 MHz for an output on 1296.xxx

    a jumper to choose the frequency (if you have a simplex transceiver, like IC-705 or FT-817 or a duplex transceiver like IC-9700)


    maybe a 2.0 version of this ground station?

    hello everyone,

    I have an IC-9700 that I use in my fixed station with a stabilized LNB (on 25 MHz), a DX-Patrol Down Converter and a DX-Patrol Up Converter. Both piloted by GPSDO.

    I modified the PICs 12F675 to receive on 1289.794 (by exemple...) and transmit simultaneously on 433.794

    There is no difference in frequency and full duplex is possible : I listen myself with about 250ms of delay (rise / fall time of radio waves)

    I will further improve my frequency accuracy by equipping my IC-9700 with the LeoBodnar kit.

    the new documentation (by ON4IQ) is online : https://www.dxpatrol.pt/files/QO-100GS_1.pdf

    with pictures and description of the PTT

    on the simplified diagram in page 4, you can see that only the synthesizer ADF4351 switch beetween RX and TX

    apparently no switching of RF 432 input / output between RX and TX

    median beacon of QO-100 is 10.489,750 MHz

    to receive it on 432,750 MHz, OL of LNB must be on 10.057 MHz

    10.057 / 390 (internal PLL of LNB) = 25,787 1795 MHz x 64 = 1650,379 487 (PLL of the Ground Station)

    in transmission, for the same frequency, tx must transmit on 2400,250 MHz

    for a radio (FT-817 or IC-705, or other...) on 432,750 MHz, OL must be on 1967,500 MHz


    in the Ground Station, internal PLL must switch beetween 1650,379 487 and 1967,500

    to be checked with a sniffer and a spectrum analyser with high precision ( external 10 MHz reference)


    I am going on vacation with my portable station but on my return I will take precise measurements


    about the supplied LNB , it is a "standard" LNB of DX-Patrol

    if you inject 25 MHz, output is on 739,750 MHz

    if you inject 25,787 1795, output is on 432,750 MHz


    it would be necessary to do "reverse engeenering" to modifiy frequencies (control with a PIC ?) and external connection for a RX on other band than TX (1289 / 432 by exemple)


    I have already changed the PICs 12F675 on DOWN Converter and UP Converte MK3 of my DX-Patrol to get frequencies that suited me on my IC-9700


    to be continued...

    F1FCO

    hello, I am a french hamradio, new on this forum

    is it possible to write in french ? or only in english ? I can use a translator...


    I own this DX-Patrol Ground station and I would like to share my experience with this converter

    In France, many hamradios use the F6BVA converter which is also half-duplex converter :

    https://f6bva.pagesperso-orang…V3%20QO100%20complete.pdf


    and aniway, if you are using an FT-817 or an IC-705, these transceivers are not duplex !


    73s from F1FCO, south of France