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Re: Beginner birds

> I suppose some people might consider the FM satellites to be better 
> beginner satellites because less equipment is required.  This is true, 
> but the FM satellites typically require a steerable gain antenna to 
> hear the downlink reliably.  And many of us believe that the quality 
> of the user experience is very poor.  I suspect that FM satellite 
> chaos and congestion could never be eliminated, no matter how much 
> resources we threw at the problem.  Suppose we had a "super Echo" that 
> had 10 FM channels, each with 8W PEP downlink power.  It would be easy 
> to hear with an HT, and all 10 channels would probably be congested 
> during evening and weekend passes.  How many of those legions of users 
> would be motivated to join and support AMSAT?  How many would be 
> motivated to upgrade to HEO satellites?  I don't know, but FM 
> satellites seem TO ME to be kind of a dead-end, with no gradual 
> upgrade path to "better" satellites.  I think the best entry-level 
> satellite is Mode A, which offers a quali!
>  ty user experience and a very EASY TO HEAR 10m downlink.  The 2m SSB 
> uplink is more difficult than FM satellites, but it offers an upgrade 
> path to the higher satellites.  But maybe my thinking is biased by the 
> fact that I'm an "old timer" who became a ham when HF SSB was the main 
> attraction of ham radio.

My $.02:

I have to agree that in a lot of ways there's "nowhere to go from here" 
when you've gotten good at making contacts on an FM bird.  It's 
essentially the same experience as hitting your local repeater on the 
TV tower, except it's crossband (not hard with the right radio, you can 
do it with a TH-79A or FT-50RD or any other full duplex HT) and the 
repeater is moving.  FM is very unforgiving when you have literally 
hundreds of other operators trying to hit the same repeater all at 
once, especially when some of them up the ante and fire up their 300W+ 
brick amps to capture the uplink over everyone else.  Eventually even 
that doesn't work.  Add to that the fact that FM birds are typically 
very low orbit LEO sats and a good pass may be a few minutes at best, 
and you can see what a frustrating experience it can be even on a good 

Add to that the fact that FM transponders are necessarily more complex, 
and consequently more failure prone, than SSB transponders (which can 
be as simple as 
amp->antenna!), and SSB's tendency to sound natural even with multiple 
stations talking at once -- just a lot of people talking at the same 
time -- and it becomes evident that SSB is a superior and far more 
versatile mode.  Add to that the fact that it's SIGNIFICANTLY narrower 
and a whole lot cleaner in most cases, and lends itself to a whole 
range of other modes like PSK31 that take advantage of its linear 
nature, and you begin to see what a dead end FM is, technically 

I have to admit, I've tried FM.  Never was able to get on AO-27, and 
I've never seen anyone else actually get on the downlink of an FM bird 
either.  It was such a frustrating experience that I gave up on it.  
Due to financial constraints I don't have an all-band all-mode rig, but 
trust me, you won't hear me on sats until I do, because I don't see any 
need to try FM again .. it doesn't lead anywhere for me at least ..

"Go ahead and do it, you can apologize later." -- RADM Grace Hopper, 
"The sunset is an illusion, but the beauty is real." -- Richard Bach

Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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