[amsat-bb] Re: New Control Software

Colin Hurst cjhurst at bigpond.net.au
Fri Feb 19 16:36:22 PST 2010

Further to Drew's comments I would confirm the 1268.703 uplink.
One further hint besides deviation and frequency, is to set the TXDelay to
1000 milliseconds.
This will ensure all the switches or relays in the system have settled
prior to issuing the uplink packet.
If you find this to be the "issue", reduce the TXDelay in 50 or 100
milli-second increments till you have reliable acks.

When AO-51 was flipped and favoured the Southern Hemisphere I was able to
get acks from horizon to horizon and rarely did it double request. I use 25
watts output via about 12 metres of 5/8 inch hard-line to a 15 turn
With your system you should do just fine.

The other issue that Drew commented on was deviation.
In the absence of test gear, a method I have used, is to listen to the
audio level on the downlink, then preferably compare your TX signal level
in the same Transceiver, but a separate RX will suffice. It will be very
apparent if you are under or over deviating.
Not very scientific, but when you have limited test gear, its a way
Colin VK5HI.

> -----Original Message-----
> From: amsat-bb-bounces at amsat.org [mailto:amsat-bb-bounces at amsat.org]On
> Behalf Of Angelo Glorioso
> Sent: Friday, 19 February 2010 14:07
> To: Andrew Glasbrenner
> Subject: [amsat-bb] Re: New Control Software
> I appreciate the helpful hints. I will try it again once it comes back
> up on 1.2.
>  Again, thanks for all your efforts in keeping AO-51 one of the leading
> satellites to use.
>  My hat off to you!! :-)
> ----- Original Message -----
> From: "Andrew Glasbrenner" <glasbrenner at mindspring.com>
> To: "Angelo Glorioso" <n5uxt at hotmail.com>
> Cc: "AMSATBBS" <amsat-bb at amsat.org>
> Sent: Thursday, February 18, 2010 9:28 PM
> Subject: Re: [amsat-bb] New Control Software
> > Angelo Glorioso wrote:
> >>
> >> I see! As for low usage of the BBS, well, most of the folks that used
> >> GO-32
> >> either don't have 1.2g or have not been able to get into the
> AO-51 BBS
> >> at all
> >> since the new configuration was put in place. I have been unable to
> >> use AO-51 BBS with
> >> a 70 watts brick on 1.2g, a directives system 23 cm RHCP 12
> turn helix
> >> 14.5 dBic gain,
> >> 1/4 inch heliax coaxial cable after many days of trying. I can into
> >> AO-51 using voice with
> >> no problem. I know the frequency is a little off and have tried
> >> adjusting but no luck.
> >>
> >> I just wonder if the BBS was in V/U mode how many more users would
> >> show up.
> >> Can a schedule mode be requested for the BBS for V/U???
> >>
> >>  Oh well, as you said, it is a low priority.
> >>
> > V/U BBS was discontinued because it interfered with control of the
> > satellite, so no, we won't be scheduling it without the
> upgrade even if
> > requested. We have many L/U users on several continents, but it does
> > require a very good station. The equipment you describe should be
> > adequate...it's similar to what I use. The deviation and frequency is
> > very important to be successful. My uplink is about 3 khz high than
> > listed. Since you have an excellent L/U analog uplink, I'm
> confident the
> > devil is in the details with your digital setup.
> >
> > We've had a lot of other challenges to keep AO-51 running and healthy
> > this year and last. I'm sorry if you don't agree with our
> priorities. I
> > was working on a more comprehensive explanation to the separate
> > identical email you sent this morning. You'll have to excuse
> me if I was
> > a little kurt in my answer after you pressed the question via -bb.
> >
> > 73, Drew KO4MA
> >
> _______________________________________________
> 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