DXpedition QRM - my personal opinion - Chris GM3WOJ/ZL1CT                  18th September 2009

I am disappointed by the level of deliberate QRM that the FT5GA DXpedition is experiencing in their first few days of operating. There is no excuse for this bad behaviour, which is slowing down the QSO rate and will deny many people their first QSO with Glorioso.

The psychological state of the jammers is a mystery to me - perhaps they have called for hours without success, then think "well if I can't work them I'll try to stop others working them" - who knows - I suspect a lot of it is just 'RF vandalism'.

It is worth considering what a DXpedition can do to minimise the effects of jamming - obviously if the jamming is persistent and 59+40dB then all they can do is QSY on that band, or move to another band or mode where the jamming station's signal is reduced by propagation. Here is my list of things that a DXpedition could do to minimise the effects of jamming - these comments are general * * not directed at FT5GA * * (but some of these points may be relevant to this DXpedition)

1.    Don't 'hype' the DXpedition too much before the event. Over-ambitious claims before a DXpedition result in excessive expectations, which then quickly turn to frustration if things don't work out. Everyone prefers a solid QSO to a flashy website, Twitter feedback, streaming video, etc, etc !

2.    The DXpedition organisers should have a realistic view of what is achievable with the resources at their disposal - for example a DXpedition to an entity which is very rare should concentrate on CW and SSB only, on 40m, 30m, 20m and 17m at this low point in the sunspot cycle and not be tempted to over-stretch limited resources by trying to do too many diverse bands and modes. Specialist sponsoring groups may put pressure on for exotic datamodes etc, but it is far better to consider the needs of the majority - a whole generation of new operators may need this rare entity for an all-time new one.

3.    Operator experience - absolutely crucial - a 50kHz wide wall of stations calling can only be handled by *very* experienced operators. DXers do not necessarily make good DXpedition operators - they may have little or no experience of being on the receiving end of big split pile-ups. In general good contesters are much better at handling and controlling pile-ups - and also at copying signals with heavy QRM. Contesters think about QSO rates and logging accuracy.

Unfortunately (it is human nature) many operators are not amenable to 'training' - they regard themselves as top operators who don't need trained - sadly they find this is not the case when it is too late i.e. the wall of impatient stations is calling them. When you hear the word 'Again' regularly from the operator, you know that he is not experienced - he should be sending the part of the callsign he has heard then 59 immediately, then checking or confirming the full callsign on the next transmission - saving time.  Ignoring deliberate QRM is the best policy, but sometimes it just cannot be ignored and you have to change something to make QSOs.

4.    Signal strength - absolutely crucial - if the DXpedition signal is strong, QSOs can still be made through moderate jamming - jammers soon give up if they see no effect of their actions. Obviously an amplifier is essential, but choosing the correct antennas is the key - for example a Spiderbeam at 10m or 12m above ground level (and perhaps too close to the metal roof of a building or other nearby objects) is not likely to be a very good antenna on e.g. 20m.  If the DXpedition is somewhere where the beach is accessible, verticals or DJ2YA's 2-ele vertical arrays are the key. If you can't put these vertical antennas on the beach, the choice of antennas becomes much more difficult. Experienced DXpeditioners would probably know to have different antenna options available if they are unable to find out exactly what the local conditions are - or to change existing antennas if they are not working as desired.

Receive antennas are essential if operation is planned on 160m and 80m (and maybe 40m) - especially near the Tropics - even a single Beverage (which is easy to install and could be shared or repositioned) would make a significant difference.

A strong signal makes the pile-ups easier for the DXpedition operators to control and makes the DXpedition easier for you to work. Maybe taking one 1500W amp would be a better idea than 2 x 500W amps, especially if only one or two stations are going to be active all the time.

5.   Propagation knowledge - also crucial - if the DXpedition has limited antennas or restricted power, it can compensate to some extent by utilising band openings to their full extent - not turning the beam away from one area where the opening might be short each day to another area where the band is open for many hours, just because the second group of signals are stronger and easier to work at that particular moment.

6.   The DXpedition should have *everything* ready to go before making even one QSO. This is very important - a clear start date/time for the DXpedition (if possible) prevents frustration building and rumours starting. On a rare entity the temptation is to start making QSOs as soon as you arrive - it is better to get everything sorted out, have a rest if necessary, then face the 'Eu Zoo' with a fully-charged personal battery !

7.    If they have internet access, the DXpedition should let everyone know exactly what is happening, at least daily if not more often. Always include the day/date/time in these postings - not just 'today' or 'tomorrow' which are really meaningless. If the world is waiting, they will wait more patiently and calmly if told e.g. "we intend to be fully QRV by 1800 UTC on 20th April"

Just my 50p/50c worth !    I hope things settle down for FT5GA, propagation improves and they make lots of QSOs.

73   Chris   GM3WOJ/ZL1CT                                                   gm3woj   ...<aat.>   talk21.com

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