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Re: Hamsat, Good copy



Hi, All

Made my first QSO via HAMSAT indian transponder at 11:45 UTC with Terry
G1WPR and than with F2LQ and EA4CYQ during orbit Nr 18

Having operated via satellite beginning from OSCAR-6 my opinion is that
the HAMSAT transponder linearity and the quality of SSB modulation are
perfect.

In addition the sensitivity of the indian transponder is very high because
only 5 watt are necessary for a good QSO and apparently no distorsion
due to intermodulation products or reduction of sensitivity was experienced
durind orbit Nr 18

I had no time to look if the carrier of the beacon was ON or OFF

The circularity of  both uplink and downlink are proven to be RHCP so that
no problems with most of the actual 2 m and 70 cm antennas already in
operation.

Since the transponder is of the inverting type the doppler compensation at
the ground station can be manually made by hand with no problems adjusting
only the uplink frequency while speaking.

The last keplerian elements distributed on this BB are accurate enought
because I lost HAMSAT signals just few seconds after the computed LOS

During orbit Nr 18 the most part of the traffic was concentrated +/- 10 KHz
around the center of the passband 145.900 MHz but following the old habit
of satellite users CW is recommended in the lover part and SSB in the upper
part of the passband.

Now finally I can say that we have again a real satellite for communications
using a FDMA (frequency Division Multi Access) transponder for CW and
SSB wich are the most efficient type of modulations and this is enough for
me in waiting for the future with P3E

In addition HAMSAT can be operated using any old VHF/UHF equipment
for the uplink and for the downlink and more important it is alwais in the
same frequency bands.

I would like to thank very much AMSAT-India and William PE1RAH for
theyr effort and succesfull job but particularly ISRO who demonstrated
again that an enterprise of great moment like this can be made at no cost
for the exclusive benefit of the Amateur Radio.

Best 73" de

i8CVS Domenico

----- Original Message -----
From: "OZ1SKY Brian" <amsat-bb1@houge.spamfree.dk>
To: <amsat-bb@amsat.org>
Sent: Friday, May 06, 2005 10:40 AM
Subject: [amsat-bb] Hamsat, Good copy


> Hi.
>
> At round 0813utc i had a good copy of Hamsat, signal up to S7 on a 7deg
pass.
>
> Congradulations to everyone at Hamsat.
>
> Regards
> Brian OZ1SKY
> ----
> Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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----
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