[amsat-bb] Re: DO-64

wouter weggelaar wouterweg at gmail.com
Sat Sep 13 02:18:09 PDT 2008

Hi all,

Please keep in mind that Delfi-C3 has no active attitude control
system and therefore does not have a constant polarization sense as in
slowly tumbles trough space.
So it is important to switch polarization both on uplink and downlink.
The beacon is about 10dB below the transponder PEP, and off course the
transponder PEP is shared between transponder users.
A 2m pre-amp will be a huge improvement on your station and is well
worth considering the expense.
The beacon and transponder of Delfi-C3 are switched on together, so
once you hear the CW beacon the transponder is also on.


Wouter Weggelaar
Delfi-C3 team member

On Sat, Sep 13, 2008 at 10:16 AM, Patrick STODDARD (WD9EWK/VA7EWK)
<amsat-bb at wd9ewk.net> wrote:
> Hi Mark!
>> My attempts to upliink to DO64 with approx 200W eirp using SSB
>> have not worked.    I have made numerous VO52 contacts so I am
>> fairly sure my gear is working okay.
> I've also made contacts on VO-52, to confirm my portable setup (two
> FT-817NDs, TX radio at 5W, Arrow Antennas handheld 2m/70cm Yagi)
> works OK for U/V operation.  For DO-64, I can hear its CW beacon on
> most visible passes when it is operational.  As for the transponder, it
> is much weaker than VO-52.  I can hear my own CW through it on
> most passes, but for SSB I need to wait until the satellite is above 40
> degrees elevation to hear my own voice.
> So far, no QSOs on DO-64 yet.  Until I get a 2m preamp, I won't have
> as many opportunities to make QSOs on DO-64 compared to VO-52.
>> I'm going to wait untill I hear an actual VO52 QSO before I spend
>> much more time on the TX side of things.
> Probably a good thing.  I did the same thing initially, and then started
> working on tuning my radios so I could keep hearing myself on the
> downlink.  After that, I worked on keeping up with other stations so I
> could make some QSOs and have nice conversations.  Computer
> control is right now not a high priority when operating portable, but
> eventually I will make that happen.
> Good luck working on your station.  I hope to work you soon on VO-52
> or some other satellite - maybe even DO-64.
> 73!
> Patrick WD9EWK/VA7EWK - Phoenix AZ
> http://www.wd9ewk.net/
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

More information about the AMSAT-BB mailing list