The new Icom IC-705 is (NOT?) ready for QO-100

  • Hi Peter,


    it is just a simplex transceiver, but i always use the same QRG stabilized by GPS for TX and RX, so there is no need for a satellite mode.


    The waterfall display for transmission check can be achieved by the WEB-SDR or with a tablet with the SDR-Console / RTL-Stick which i have built in at my transverter.


    73, Mike

  • It is really important to actively monitor your downlink, not just to be able too. When I mentioned this in the UK there was a lot of pushback. Out of the bad signals I see, almost none of them are from people using SDRs and almost all of them from people operating simplex. The IC705 is an SDR so hopefully it will be good, but I fail to understand why ICOM did not make the radio duplex! It makes no sense. The IC9700 is almost the same price and must have much in common in its design and is duplex.


    Mike

  • @G0MJW


    Hey Mike,


    the radio is really cheap for all the features that it have, including battery operation from 160m....70cm.


    If they will built in another complete receiver like in the IC-9700, this will take space and about 500-800 EUR extra.


    I have never used the satellite mode of the 9700, it is annoying to listen to the own voice with a latency of 200-300ms.


    A better choice is, to have always running a spectrum analyzer in parallel like me, or to watch the own signal with one of the WEB-SDR's or by the SDR Console.


    For me is the IC-705 perfect for the next holidays with a Juma 1000 PA and my 45W 2.4/10GHz GPSDO Transverter, where a Pluto is included as well.


    The worse signals on the satellite are resulting in worse operators, or old equipment, not in a missing duplex mode :)


    73, Mike

    • Official Post

    Hello Mike DK1ML


    it is annoying to listen to the own voice with a latency of 200-300ms.

    No, its not annoying for a satellite operator, its fun and just a habituation. I can understand you, for many shortwave operator who sprung on the QO-100-train satellite operation is a new field. In a 20m-contest I would make no QSO.

    The worse signals on the satellite are resulting in worse operators, or old equipment, not in a missing duplex mode :)

    That's definitely wrong, also with a :). I'm QRV with my old Kenwood TS-711E/811E duo with a Datong R.F. Clipper and have a clean signal on the transponder. The worse signals are from the operators who can not configure there Pluto's correctly. If you have your whole rig under control, Software with SDR and Hardware, you can have a nice signal with every rig.


    73

  • Hey Thomas,


    after more than 1 year QO-100 operation and 1.000 QSOs i am familiar with all kinds of playing the SHF-game :) The own voice is still annoying to me !


    It is always the operator if something goes wrong with the signal quality, sometimes the equipment is another obstacle. As a HiFi-SSB fan, the low bandwith of vintage transceivers is also a reason for an upgrade.


    The really bad operators are turning the vfo knob while transmitting, to find the actual TX frequency. This is as bad as an offset, that the most not GPS controlled stations have with their QSO partner.


    But this all is not an issue of the new IC-705 if the right old man is sitting behind it.


    Have a nice weekend.


    73, Mike

    • Official Post

    It is always the operator if something goes wrong with the signal quality, sometimes the equipment is another obstacle.

    Agreed, its always the operator - and his equipment.


    The really bad operators are turning the vfo knob while transmitting, to find the actual TX frequency. This is as bad as an offset, that the most not GPS controlled stations have with their QSO partner.

    That's bad and wrong operating, this has nothing to do with new or old hardware. I'm only turns the RIT. Runs it out of 9.9 kHz because my LNB, then I tune in the PSK-beacon again and calculate the RX-frequency new with my self written Software.

    But this all is not an issue of the new IC-705 if the right old man is sitting behind it.

    Thank you, I'm 62 now. ;)


    Have also a nice weekend and I hope we hear us again on the transponder.


    73

    • Official Post


    Hi Mike,


    I know and trust that you are an experienced person and you know what you are doing.. no problem..



    I was not only thinking about QO-100, but also about portable QO-100 and LEO satellite operation..


    Conclusion: The ICOM IC-705 is definitely NOT READY for Satellites...


    So in this case the IC-705 is nothing special or new... it's a step back, in particular if you don't want to carry another computer with an SDR...



    The other point is about simplex operation:


    We have discussed this here and elsewhere many times and the ignorance to rules given by the QO-100 Transponder Bandplan and Guidelines is sometimes disappointing. In "portable" operation it does not help at all, if you don't have internet... and to completely depend on an internet connection to a WebSDR, is not what I think is good practice. It's OK when you are just starting to get up on QO-100, but it should not become a standard and it should not be promoted as a good solution..


    On AO-40 the time delay was twice as much compared to QO-100 because of 60.000km apogee :)


    Sorry, I have taken the liberty of modifying the title a little bit ;)


    73s Peter

  • DB2OS

    Changed the title of the thread from “The new Icom IC-705 is ready for QO-100 :-)” to “The new Icom IC-705 is (NOT?) ready for QO-100”.
  • Hi Peter,


    i am always operating my transceivers in simplex mode, no matter of the capability of crossband operation. There is no difference to a separate setup for rx/tx, because i have an option to monitor the feedback from the satellite at any time.

    There are provisions for a Pluto, TCXO RTL-Stick or just another analog receiver.


    We are in 2020 and not in 1950, so it should be no problem for a licensed ham to keep rx and tx on track without separate radios or the usage of a pc.


    It depends on the quality of your over all setup and a good working stabilisation.


    Which setup for (real) portable use do you prefer?

    The IC-9700 is not a realy good choice for field operation.

    What is the alternative? Two unsynchronised FT-817/818 ?

    Or IC-705 twins - my choice.

    The Adalm-Pluto is not an option either, because it needs a pc/laptop.


    If the the equipment is designed in a perfect way, the signals are as good as from a shortwave radio.

    Just turn the dial to the received station, hit the ptt and be transceive, thats the goal :)


    Have a nice weekend.


    73, Mike

  • Hi Peter,


    I can agree that the IC-705 is not the best solution for LEO satellites but in my opinion it is quite suitable for the QO-100.


    We have to monitor the downlink and we can do it in the following ways:


    1. WEB SDR - requires the Internet and we do not like it - removed


    2. monitor on the transceiver in sat mode - this is not the case in the IC-705 - removed


    3. monitor on a separate transceiver


    4. monitor on a separate receiver


    If I know correctly nowhere in the rules does it say that we should monitor satellite’s downlink only on the same device from which works in the uplink. Right?


    If so both of the options 3 & 4 are suitable.


    In my QO-100 transverter I have two RX outputs from LNB - one goes to the 739 -> 144 converter and then to the satellite transceiver (like IC-9700) , and the second output goes to an external VHF receiver for monitoring - for example, the AOR-3000 VHF/UHF scanner or standalone SDR RX (without PC).


    73 de Karen, ra3apw

    • Official Post

    Hi Mike and Karen,


    sure you can use a second transceiver or separate monitoring receiver, but than it makes the IC-705 no more special compared to others.. at least not at as satellite transceiver. Indeed, it's still a nice portable device and if you own two of them still no too heavy.

    Maybe we'll have to wait a little longer, surely ICOM didn't want to have a direct competitor to its own IC-9700. But a smaller/lighter portable version of the IC-9700 would be very interesting for many QO-100 users, but also especially for friends of the LEO satellites., no need for 50/100W Output on satellites..


    73s Peter

  • Indeed - what would be good would be a IC705 with just a few milliwatts output and fully duplex and full coverage. Not impossible. Several SDRs already do that, they just lack the filter banks and integrated computer that generates the look and feel of a traditional radio. Then a bolt on amplifier would allow whatever was needed, from 1mW to 1kW. This will be an unpopular statement but I think the IC-705 is disappointing. The fact it can't do duplex means it is essential to have a second RX for the linear satellites. Even if Icom don't produce an update we can be sure someone in China will and it will be considerably cheaper with "good enough" performance for most people and yet bad enough performance to annoy VHF weak signal operators. Icom missed an opportunity, let's hope they fix it.


    So to the point. There has been several times now "I know my frequency comments". We don't have to just know our frequency but also our power and if not listening or looking at the waterfall of the downlink how do we know if we are not too low or too high power? I can imagine "I know my power" comments. Well, evidence seems to suggest far too many clearly don't know their power and ignore Lila as they don't hear it. Remember, the owner of the transponder probably doesn't care if you drift or have a poor signal, or trample on top of someone else, but they absolutely care when someone sends too much power. Too much too often and it will be switched off. So lets be clear about this. If you are not operating QO-100 duplex, you should not be operating at all, period.


    Mike

  • Hallo,

    is there anyone outside who knows if the IC705 can show the filter curve in the Display. Just like the Console does. And many other SDRs do also. If not, this will prevent me to substitute the FT817. As far as I know, Icom doesn't like to show the filters in their radios. It's hard to understand. Probably an update will bring it. I do not ask, if a two tone signal is avalaible. Some lines code more and it is done.
    Have fun, beside my questions

    73
    Andreas

  • Andreas, look at minute one and ten seconds if that's what you're looking for.


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  • Hallo Lucio,
    thanks for the picture but this is not what I expect. I would like to see the filter curve (may be highlighted) in the display.

    Here you see a part of a spectrum. The filter curve is gray.


    In the IC705 spectrum there is just a white line, this is the carrier frequency.

    73
    Andreas