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Re: TMSAT Status

At 19:29 7/11/98, you wrote:
>At 06:58 11/07/1998 +0100, you wrote:
>>The following keps are accurate for tracking the spacecraft (Note that the
>>object number is not the final TMSAT object).
>>1 25395U 98043B   98191.87373682 -.00000045  00000-0  00000+0 0    24
>>2 25395  98.7944 261.8948 0001516   6.1903 313.0257 14.22263117    96
>>If you can receive the UOSAT VLSI telemetry format at 9600bd FSK, please
>>let me know - we may be interested in capturing telemetry from the
>>satellite when it is not in view of Bangkok.
>>Chris Jackson G7UPN / ZL2TPO
> Ok, so when I load these into Instantrack I get the "mon 10 line checksum
>failed message. When compared to other elsets the checksum even looks
>wrong. Am I stupid and missing something... it has been a long day?

If he changed something like the catalog number, the checksum would most
likely be wrong.  Since he says the object number isn't the final TMSAT
number, I'm curious what is the actual number.  I'd be happy to re-compute
the checksums based on the real catalog number.

>BTW, how is the mod(ulus?)10 checksum calculated? I seem to recall having a
>similar problem with some Iridium elsets.

It's computed as follows:
1) Add up all the digits on the line counting a "-" as a "1"
2) Save only the one's digit as the checksum (this can be done by a 
modulo-10 function or by subtracting enough 10's from the sum to keep the
answer >0 and <10).

Ken Ernandes

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