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Re: Re: Thoughts on future "FM birds" (was: proposalfor maximizing fm le o contacts)

on 8/17/00 1:22 PM, Randolph Kohlwey at kohlwey@xmission.com wrote:

> At 07:12 AM 8/17/2000 -0500, you Jon wrote:
>> on 8/17/00 1:00 AM, Tony Langdon at tlangdon@atctraining.com.au wrote:
>>> Well, ideally, the linear birds are better suited to longer ragchews, as
>>> they have inherently greater traffic capacity, but perhaps more FM
>>> transponder space might be a good idea.
> But listen to them during the week.  It is usually 0, 1 or 2 QSO's going on.
> On weekends you may get up to 5 QSO's.  Is that a good use of a 100kHz
> wide uplink on 2 meters?

Yeah.  No one uses the SSB birds because all the advertising and marketing
effort is put into advocating the FM birds.  So people don't get the
stations they really need.  It is sad.

>> Better yet, move to the SSB birds!  C'mon Tony.  You seem like a good op and
>> are knowledgeable about satellites.  There is so much more out there than FM
>> birds.  I'd rather get more SSB birds up there than FM birds as they are so
>> much more useful and useable by people.  FM birds have too many limitations.
> But are the one up there now being used that much and is there room to
> put new one up on LEOs using 2 meters.

Let's see:  With all the FM birds, no.  But we have RS-13, RS-15 (barely
works), FO-20 (dying) and FO-29 as SSB leos.  FO-20 is expected to be on its
last leg.  RS15 is so weak that its difficult to use.  RS-13 is used quite a
bit.  FO-29 is in digital mode or digitalker mode some of the time.

Let's see, we have the following "FM" or packet type birds up there:

AO16, LO19 (??), IO26, AO27, UO14, UO36, TM31, KO23, KO25, the list goes on
and on.

Who's hogging the channels on 2 meter?  Certainly not the linear transponder
birds!  And the 1200 baud sats are hardly used these days except for a small
amount of APRS traffic.  They are taking up channels and have very little
use.  Probably less than the linear birds.

> Would you donate to a call for money from AMSAT to fund a LEO transponder?


> Another question I have is if a microwave transponder is useful on a LEO
> satellite.

Isn't experimenting what ham radio is all about?  Why don't we try it?
Now in the microwaves, we DO have enough bandwidth to run a multi-channel FM
bird.  That would be interesting too.

> Why not another U/V Fugi like bird? There is not room for much more in the
> satellite segment of 2 meters. We are all ready sharing many uplinks
> between the birds.

Yeah.  With a lot of little used 1200 baud birds and a lot of packet BBSes
up there.

> So that leave the microwave bands.  We should use those bands. Will the
> hams that worked AO-10, A0-13 and hopefully soon P3D be able to deal with
> the Doppler?  It is really going to be fun to track the S-band Doppler on a
> SSB signal. Hey just the uplink on L-band is going to change a lot.   It
> will force many of us to go to full computer control.

Could be.  We'll all find out on P3D.  However, at Apogee, I will argue that
the P3D doppler will be very little since the satellite appears not to be

> I think a better use would be to use the transponder more for digital voice
> as suggested my Phil Karn.

Interesting concept.  I think using spread spectrum would be a great way to
go.  A SS bird would be good as well.  And many people could use it at the
same time too.

>> It's sad because we are wasting resources and money on
>> a mode that is NOT appropriate for widespread use!
> Is it your's or AMSAT's money and resources?

I am a member of AMSAT.  I give money.  Therefore, it IS my money.  It's ALL
our money.

> Are there plans out there on how to build a space worthy
> ham transponder?  I have not seen any articles in the AMSAT Journal, QST,  or
> QEX.

Gee, I thought that you could just go to Radio Shack and buy the parts and
dead bug it together.  I thought that was the latest satellite concept.

* OOPS!  Sorry for being politically incorrect.

> When was the last time AMSAT-NA built a transponder. Even if the plans
> were there for the ones they did build I am sure some of the part they used
> are unavailable today.

I think they helped with AO-10, AO-13 and P3D.

>> I bet as many hams that
>> get into satellites leave due to what they hear and see on the FM birds.
>> More won't help.
> Well I think UO-14 took a lot of the load off of AO-27.

NOT!  The same guys that hang out on AO-27 move over to UO-14 when it's
overhead and vice versa.  UO-14's just easier to work.

>True some of us might
> be on every pass that we can of every FM bird.  I am looking for 22 more grid
> squares in the US.  They show up a lot more on the FM birds than on the Fugi's
> where you can often hear the same people calling CQ for most of the pass
> on the daytime Mon-Fri passes.

Yeah, but if everyone went to an SSB bird, all those grids would be there as
well!  And you don't necessarily need a really wide transponder bandwidth
either.  Why make it 100 KHz.  Why not put a linear transponder in the same
25 KHz bandwidth as an FM bird?  You'd take up less space and have enough
room for several Qs simultaneously.

> We we going to turn JAWSAT over a FM voice a lot sooner.

You mean JAWSAT works?  I thought it was a dead package.  Good secret you're
keeping there, Randy.


Jon Ogden
NA9D (ex: KE9NA)



"A life lived in fear is a life half lived."

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