Re: [AOCC] ARRL Sep VHF K7HP Single Op LP


Keith Morehouse
 

I agree with K7HP's assessment of FT8.  For contesting, not only is FT8 intolerant of static crashes, but also of meteor pings, of which 6M has in abundance.

 Yesterday, KK6MC Rover op Mike, WB2FKO and I also found another problem with FT8. It is totally intolerant of multi-path.   We attempted a ~300 mile 432 MHz path over the mountains from DM58 to DM44.  We made a snap decision to use FT8 because of experience earlier that morning on a similar path.  Even though my signal was very loud in DM44, Mike could not get a decode.  We cycled through JT65 (where the multi-path problem was painfully obvious) to MSK144 and finally just went to CW (they were having equipment issues which took them off CW without a re-cable of their 432 system, so that mode wasn't immediately available).  Why didn't we just choose CW as our starting point, you ask ?  It was a combo of the aforementioned equipment problem AND the fact I was running 13 dB more power on my end (1000 vs 50 watts - the allowed maximum in NM/AZ).  A good signal on the south end of the path did not necessarily equate to easy copy on the north end.

The take away lesson here is obvious.  Intermountain paths are full of multi-path situations.  This multi-path was not immediately obvious on the FT8 waterfall display and no amount of digital fiddling about could produce a decode on a loud signal.  Meanwhile, on my end, with a considerably weaker signal and no multi-path, I was decoding 100% of the time.

A smart operator must consider all of the WSJTX modes as tools in the box.  No one tool is good for all circumstances.  This is MY major issue with FT8.  Most casual operators on 6M have given up on SSB operation, even during band openings and are exclusive users of FT8.  During a contest, when the goal is working as many stations as possible, they are limiting the run rate for everyone, serious and non-serious ops alike.  Unfortunately, many serious ops are dragged along in the rush, saying 'Well, we need to abandon SSB also and follow the contacts'.  This is impacting scores, impacting the 'fun factor' of 6M contesting for many and, most worry some to me, moving a lot of very experienced operators away from VHF contesting and off 6&2 in general.

-W9RM

Keith Morehouse
via MotoG


On Mon, Sep 16, 2019, 8:53 AM Steve London <n2ic@...> wrote:
On 09/15/2019 11:21 PM, K7HP wrote:
>
> ARRL September VHF Contest - 2019
>
> Comments:
> I just cannot get much interested in contesting using FT8 .
> Have no particular issue with using FT8 day to day but
> as a contest mode ESPECIALLY when I can hear by ear
> at least 75 percent of the signals I work on FT8 and could work
> them on CW in 5 -10 seconds .
This seemed especially true on 6 meter FT8. A static crash during the RX cycle
would eliminate any chance of a decode. My brain would have easily filled in the
missing dot or dash. Also, there was rapid QSB on most FT8 signals (weak Es ?
meteor trails ?). WSJT-X was also intolerant of that, whereas my brain and CW
would have had no problems.

MSK144 would have been far more appropriate than FT8.

73,
Steve, N2IC



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