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Re: ARISS.NET



On 4/25/01 6:58 PM Francisco Costa (fcosta@mail.telepac.pt) wrote:

>After a couple weeks digipeating via ISS,  I've been wondering why
>my APRS spots weren't displayed on ARISS.NET web page.
>Only today I found the reason: instead of a "\" beetween Latitude/Longitude
>coordinates, I was using a "/".
>So, if you're having the same "problem", this will save you some time.
>
>Best 73
>F.Costa, CT1EAT
>
As Bob pointed out, either one works. The findu.com database only has a 
single packet from you in the last 60 days, the one with the '/'. Even if 
there were something wrong with the format of your other packets 
preventing your position from being parsed, the raw packet would still be 
in the database.

The process of getting a packet from your ground station to ariss.net 
goes like this:

Your packet is transmitted and echoed by ISS, then heard by an Internet 
Gateway (IGate), which forwards it into the APRS internet system, then on 
the the findu.com database. This database is queried each time the 
ariss.net page is requested.

The weak link here is the IGate. I've noticed that the signal from ISS 
has strong fades in it, which I'm guessing are caused by the structure of 
the station interferring with the line-of-sight for the antenna. The best 
chance of an echoed packet getting to an IGate is when the IGate and the 
transmitting station are near each other, and therefore share the same 
geometry. AFAIK, the IGate that you are most likely to be heard through 
is mine in Miami, so you need to transmit when Miami is also within the 
footprint of the ISS, and preferrably when your station and Miami are on 
the same side of ISS. 

Steve K4HG
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