[OZAPRS] Richard's comments following on mine (and more) ...

[Terry Neumann]

G'day Richard and others,

Thanks Richard for your comments.  I appreciate the points you have 
raised.  There is a challenge in there too, so I'll continue on if I
may...

>As we are talking of HF here we need to keep in mind the natural
>characteristics of HF operations which means we have to think on an
>international level for APRS operations on this frequency. Even if you
>are not able to here (may be not able to decode) the other 101
>(hundreds) operators they are on the same frequency as you are they may
>be able to here your signal due to conditions or their super dooper
>sensitive installation.
>
>There have been several emails sent from US and European stations to
>VK3MY providing signal reports for VK3MY-4 some of the stations that
>have sent reports are not received by VK3MY-4.
>  
>
Fair enough.    However 10.147 (or thereabouts) like much of the rest of 
the band has a huge number of signals on it - not all of them of amateur 
origin. The latter examples serve to completely obliterate any 
underlying APRS signals.   My point is that given this, it's unlikely 
that international APRS signals are likely to be a very big 
consideration for either us or them.   Even in my country location free 
from computers and RFI devices other than my own, it's hard to really 
make much of the weaker signals which are there.   I must listen more 
carefully out on the tractor at some time where the only interference is 
from the John Deere electronics.   Certainly there are DX signals there, 
but they are weak - too weak to be usable in APRS work in my obervation. 
I'm often fascinated by the CW contacts I can hear in the background 
under local phone QSO's on 10.120.     

Of course I only listen during the day - my experience with 10 megs is 
that come the darkness hours, other non amateur signals make it a lost 
cause.  I'll  have a try at leaving things on  for a few nights and see 
what  happens.   OK  - Richard, leave it at  "hundreds" but  perhaps 
include " world wide" ;-)

>The main aim of APRS HF is to track moving objects. APRS was designed
>to be a real-time tactical and emergency object tracking system. On HF
>we are very limited in our data band width (through put) it is 1/4 of
>the VHF band width with potentially a much much greater coverage area.
>Why use this valuable band with to display boring objects that don't
>move. As you state below your main interest is watching VK3BYD travel
>around the country side.
>  
>
Agreed, but at this stage even stationary objects - eg - VK5ATN home 
station - position once every hour (4.5 seconds on air) - serves to 
provide icons on a screen , essential I feel to promote interest from 
first timers looking in on what it's all about.   As more stations come 
up - sure,  lets close down non-moving non relay stations, but it's not 
a major issue at present.   

> 
>  
>
>>This mode will never attract significant numbers of other users if we
>>don't
>>make it as interesting as we can whilst people who might be
>>interested look in at the SWL stage.
>>
>>    
>>

>I disagree, the main reason people will not use HF APRS is the lack of
>a guaranteed Gate infrastructure where whey need it. People want to be
>able to get their position on to the internet so that others be it
>family or friends can see where they are and more importantly that they
>are safe. HF APRS will provide good position information to families of
>OutBack travellers via the internet (you don't have to be an amateur) if
>we have a well designed and reliable Gate system.
>  
>
Hmmm...... Well that raises a very interesting point which  I've 
discussed at length with an innovative amateur friend here in VK5 who is 
usually always in at the ground level with a new mode.   He won't have a 
thing to do with APRS even (and perhaps especially) at VHF.   The 
reason?   He says that the fact that APRS is so generously available to 
non amateur audience, creates a situation where his mobile beacons 
observed when he is far from home, telegraph to undesirables that it's 
now OK to go to his home and check out the back shed.   Paranoia? 
perhaps, but realistic too.      It's a question each of us must answer 
for himself.    Personally, I no longer run VHF APRS unless I am 
returning to my home - I never use it on the outward leg.      And while 
I'm fascinated by the possibility of my occasional outback adventures 
being able to seen by members of my family, the  indications from what 
I've seen so far from HF APRS are that it wouldn't be reliable enough to 
be taken seriously.   Unfair, unkind ? Perhaps.  Don't forget that we, 
as amateurs are prepared to accept  that these are experiments and the 
variability of propogation and other factors which can determine the 
success or otherwise of the exercise..

Personally I'd prefer to use some other means to keep my family 
informed.  There are quite a few.  That doesn't mean that I'm not 
prepared to try HF mobile APRS  in the future.   That will be covered in 
the next point.

>>From experience I could not get many people interested in VHF APRS in
>VK3 until I was able to establish a few digipeaters for people to use.
>It's not much fun talking to yourself.
>
>The 4WD HF radio network is very popular because it is guaranteed
>reliable system that offers good services.
>
> 
>  
>
Exactly.   

>>It's about positions on a map at
>>this early stage;
>>    
>>
>
>It sure is so why not get mobile on APRS HF?
>  
>
It's a question involving three factors.   Money, time, and perception 
of reward (degree of satistfaction).    I can probably get the latest HF 
TT3 chip from Darryl,  put it in my existing TT box and fit it in either 
of my two HF mobile stations (with some extensive fiddling).   Or I can 
save up and buy a  Kam box from Ross and use that.  However I need to 
stay married too?  ("how much did that cost????!!")  (Married members of 
the list will understand).

Time is also a factor in all of these issues.   I need to prioritize how 
much I spend on the hobby, and where it's likely to be the most 
rewarding.   Which leads onto the next issue.

The third point is the perhaps puzzling statement "perception of 
reward".   Of all of the various aspects of amateur radio I've explored 
in the past 24 years, APRS is the one which requires the "strangest" 
motivation to remain interested, especially for the solo amateur in 
isolation from clubs and others.   Quite simply, it's a one way activity 
- there is no feedback at all unless you have a team of friends to keep 
you informed as to how you are going.  I can't be mobile, and watch my 
station back home at the same time.  It's even more remote in some 
respects than running a propagation beacon on 6 metres.  You simply have 
no means of knowing if it's of any use at all.  

One slightly oblique aspect of the digipeating aspect discussed in past 
days here is that any mobile station who might have been operating at 
the time, and was monitoring the frequency would receive some degree of 
assurance on hearing the digipeat immediately following his own 
transmission.    That's not a reason for it to continue, but simply an 
observation on the facts - I know I've used the same principle in 
confirming the viability and strength of my own mobile beacons on VHF.
    
The lack of immediate feedback to the mobile user is one reason why this 
group is so important in keeping the interest up.   And why it's so 
important to keep feeding reports back into the system.  I have seen 
quite few stations come and go on VHF APRS in the SA area.   There are 
very few stayers (with the obvious exception of Andrew and Tony) I 
suspect that lack of feedback and therefore personal satisfaction are 
the reasons.  It could also have something to do with the very first 
point I raised, although I can't be sure.   

So one day, you may see a VK5ATN mobile icon on your  HF screens.  It 
probably won't be on the tractor though.   All day at 8.5 kph in the 
same area is hardly captivating viewing....

I am looking forward to Andrew's trip out bush  however.  It will be a 
fascinating experiment in all that this mode offers.

Just the lengthy thoughts of an amateur in comparative isolation,
Thanks for reading,
73
Terry
VK5ATN

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