Hello all,
Currently we are planning to transmit 1 Watt signal from the satellite but due to vswr losses, the transmitted power is around 100 mW. This is due to the antenna's S11 loss being around -1 rather than -10. This is for the VHF band for which we are using an antenna 17 cm long, thus such high loss. The length can not be increased much and so is the case with the electronics(power amplifier) as we are restricted by other constraints. We would love to hear some of your suggestions so as to how can we still increase the transmission power meeting all these requirements. And if not, what can be done on the Ground-Station to improve the reception. Are there satellites available which transmit such low power and still can be received? Any Help would be appreciated.
Thanking you, Aayush Yadav Team Pratham.
On Mon, Dec 7, 2015 at 9:01 AM, Nitin Muttin [email protected] wrote:
Hi Aayush,
As discussed please consider the below points.
- Fine tune your antennas in the satellite sub band on VHF and UHF. VHF -
145.800Mhz - 146.000 Mhz. UHF 435-438 Mhz.
Replace the RG -58 Cable with Heliax or LMR 400 Cable.
Move the pre amp (LNA) to the mast closer to the antenna.
Refer http://www.dk3wn.info/satellites.shtml for the list of
satellites , modes and frequencies.
- For some satellites you can use sound card based software TNC like
http://uz7.ho.ua/packetradio.htm for AX25.
73 Nitin [VU3TYG]
*From:* Aayush Yadav [email protected] *To:* Nitin Muttin [email protected] *Cc:* Mani VU2 WMY [email protected]; Somashekar S. [email protected] *Sent:* Saturday, 5 December 2015 2:27 PM *Subject:* Re: Help needed please
Hello sir, As discussed over the phone, could you please provide me with the various satellites to track, information regarding softwares and the cables. Thank you sir,
Yours sincerely, Aayush Team pratham
On Tue, Dec 1, 2015 at 6:28 PM, Nitin Muttin [email protected] wrote:
Hi Aayush,
Sure, we can discuss on Saturday after 11AM. I can be reached on 9880018675.
73 Nitin [VU3TYG]
*From:* Aayush Yadav [email protected] *To:* Nitin Muttin [email protected] *Cc:* Mani VU2 WMY [email protected]; Somashekar S. [email protected] *Sent:* Tuesday, 1 December 2015 3:40 PM
*Subject:* Re: [amsat-bb] Help needed please
Hi Nitin, I was wondering if you were free this week, we would really appreciate the help.
Thanking you,
Regards, Aayush Yadav Team Pratham.
On Tue, Nov 24, 2015 at 9:10 PM, Nitin Muttin [email protected] wrote:
Sure Aayush we can discuss this next week over a phone call. This week we have a tight schedule to the HAMFEST 2015 in Rajkot.
73 Nitin [VU3TYG] Secretary, AMSAT INDIA www.amsatindia.org
*From:* Aayush Yadav [email protected] *To:* Nitin Muttin [email protected] *Sent:* Tuesday, 24 November 2015 7:37 PM
*Subject:* Re: [amsat-bb] Help needed please
Hello Nitin,
We would love to have your help on the same. If you have any advice on how we should continue our work we really welcome the suggestions. Thanks a lot for your reply. If you could help us in improving our sensitivity, as currently we get around -110 dbm noise at the antenna but as per our calculations the power of the signal we need to recieve would be of an order of -150 dbm.
73 Aayush Yadav. Team Pratham.
On Tue, Nov 24, 2015 at 11:40 AM, Nitin Muttin [email protected] wrote:
Thanks Burns for the pointers.
@Aayush, I can help you with information so that you are able to successfully receive and decode telemetry.
73 Nitin [VU3TYG]
*From:* Burns Fisher [email protected] *To:* Aayush Yadav [email protected] *Cc:* "[email protected]" [email protected] *Sent:* Tuesday, 24 November 2015 1:28 AM *Subject:* Re: [amsat-bb] Help needed please
Hello Aayush,
Starting out with very strong signals is probably a good idea even though you can probably get any satellite that you wish with a good ground station. Start out with AO-85 for FM reception and AO-73 for SSB reception. AO-73 is especially strong during local day time during Mon-Friday (UTC). There is not transponder turned on then, so all the power goes into the telemetry.
Both of these can be received with an HT (handheld with a simple antenna) so you are very likely to receive them on any station you have and optimize from there.
I would also suggest that you might find local colleagues in AMSAT-India who would be able to tell you things of local interest (what parts are available where, for example).
73,
Burns W2BFJ
On Mon, Nov 23, 2015 at 2:16 PM, Aayush Yadav [email protected] wrote:
Hello all,
As a part of a student satellite project from India, I have a few
questions
regarding how can i improve my reception of data on the ground station.
We
have a TS2000 and have designed a few yagi antennas for uhf and vhf
band. I
would like to know some satellites on which we can practice receiving any signal. We are totally new to this system and have practiced some failed attempts of the same. Further, we would really appreciate If anyone could help on how we can increase our reception power. Any other help or advice would also be appreciated. Thank you.
Aayush Yadav, Team Pratham, IIT Bombay. _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
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Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb