Split mode operation

  • Hello,

    did you listen to the simplex pileup ? Could you copy the DX-Station in the crowd of calling HAMs ?

    No - you couldn't copy the DX. Thus the DX has to wait until everybody calms down and then can reply to one station.

    In split mode the DX has its "own" QRG and will be heard and can answer to a call sign, even when many stations are calling. Thus the QSO rate is much, much higher (higher efficiency).

    Thus in my opinion split mode for rare DX with huge pileup is also useful via QO-100.

    73 de Johannes

  • Remember, one of the reasons for duplex mode on satellite transponders is the need to constantly monitor your own emissions and signal quality. In split mode this is no longer possible for all participating stations!
    So from my point of view split mode can not be preferred.

    73s de Robert

  • And, on HF, the pile-up stations usually can not hear each other, this relieves the called station heavily because the pile-up is distributed accordingly. On the satellite transponder you can see and hear immediately where the called station is listening.

    This also reduces the advantage of split mode enormously ...

  • DD4YR

    Hello Robert,

    I have to disagree. The most important thing in a HF-pileup is the 2nd receiver (see all the top HF-radio models !). The monitoring of the pileup is essential for success in a pileup. If you have an experienced DX-OP it is not adversely when you can monitor all the pileup (neither for the DX nor for the caller). You have to observe the habits of the DX-OP and than you have to call on the "right" frequency. (As it should be in HAM radio 99% listening and 1% calling).

    As VE4SW already said full duplex (monitoring your own signal) and split is not a contradiction !

    For QO-100 I use an analogue receiver to listen to the DX and in addition a SDR to watch all the pileup and to listen (and constantly monitor) my own transmission.

    Thus I still can not see "two rules fighting" or any reason why working split via QO-100 (in certain cases) should be omitted.

    But lets look forward for an offical statement from AMSAT.

    73 de Johannes DL5RDI / AC2TR

  • I fully agree to work in split when DX is on the sat, because some stupid ham's still love to use too much power to get over the pile-up. In split, also weak stations have a bigger chance to work the dx, and as DL5RDI mentioned, you allways hear the DX station talking.

    What is, in my opinion, the benefit of working full duplex? There is no need to here yourself. Just working simplex here and never had any problems, no need to hear my own voice. Worked also in split with the FT817, 2m as IF TX band, 70cm as RX. Just check only once the freq offset between up and dwnlink, allways right afterwards.

    It's irritating that people still need to tune on the right freq, giving an echo on their modulation when they go on air because in the background some sdr-stuff's volume is too high.


  • Satellite via QO100 shouldn't count for DXCC because there is no propagation skill. If you build the capability to work one station then you have capability to work them all. Working as many different stations as you can is valid but that's not DXCC. It shouldn't matter where those stations are and all are equally valued, which is the antithesis of DXCC. Let's evolve beyond HF DX.

  • Wow, what a response ! :)

    BUT! Split mode works only, when the caller announces his split in kHz up or down here in the Shoutbox like in a DX cluster on HF. With a second receiver you have to check first, is he listening up or down, if an other caller is nearby.

    I agree with Robert, DD4YR, its not necessary to work split on a satellite transponder ("wenn ich Dich richtig verstanden habe Robert"). With discipline and short calls you can work DX. I done it to Brazil, French Guiana, India, Oman, South Africa and Mauritius (in QRP ;)).