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RE: Beginner birds



> You make some very good points, and I agree that the current 
> FM LEOs are 
> not the best "user" experience. But like life in the city, things get 
> crowded if they are popular.  And FM LEOs are very popular.  If they 
> weren't, no one would be using them.

Time to chip in from the other side of the world. :-)

In VK, most new amateurs start out with a 2m/70cm FM station and/or a HF
rig.  Good secondhand 2m SSB gear is quite easy to come by at reasonable
prices also.  The more well off will go for one of the all band, all mode
rigs such as an FT-847.

Significantly, neighbouring countries, which are mostly Pacific island
states such as Fiji, Vanuatu, Solomon Islands, etc, tend to be mainly HF
with a little 2m capability.  New Zealand is the main exception here, having
a relatively large and avtive ham population on all bands.

So, what's a good beginner's satellite to us?  One that's easy to access and
also one for which equipment is available.

For VK and ZL, the FM birds are the best for most to start out on, because
of the prevalance of dual band FM equipment in these countries.  However,
this is not the case on a number of the Pacific islands, where 70cm is rare.
FM over here has sufficient activity to be interesting, without being
overcrowded.

Mode A is another mode which suits some newcomers.  2m SSB is relatively
common over here, as well as being inexpensive, and most hams have a HF rig
or shortwave receiver for the downlink.  This mode may also suit some of the
Pacific islands (if they don't have SSB, there's always CW with the PTT
button :) ).  Doppler shift on 10m is also relatively low, so it's much
easier to learn to compensate for.  Back in the early 1990's, I had quite a
bit of fun on RS-10 using a 25W 2m all mode rig into a vertical and a
cobbled up receive setup which consisted of a piece of wire strung in the
trees and a Yaesu shortwave receiver... :-)  Urban noise levels are quite
high on 10m these days, so any new mode A bird would need to have a
reasonable power output or narrower bandwidth (to concentrate the power into
a smaller slice of spectrum) than the 40 kHz used previously.  

The only problem with Mode A here is finding people these days.  Unlike my
earlier experiences with RS-10, RS 12/13 in more recent years found me
calling CQ and talking to myself.  I did have a couple of contacts, but
these were with locals who I'd been chatting to on local frequencies and
said "Want to give the sats a go"? :-)  However, a sensitive Mode A
transponder might be of benefit here.  My only reservation is the higher
level of Asian QRM from cordless phones, etc (the same problem that plagues
the Mode J birds).

> What makes FM birds excellent entry-level satellites is FM capture 
> effect.  You don't have to have 10hz tuning steps to be able 
> to compensate 
> for doppler. 5khz tuning steps work just fine.  I don't 

True, you just plonk yourself somewhere within 5 kHz of the required
frequency. :)

> believe entry level 
> users will be able to cope with SSB doppler on their own 
> before they get 
> discouraged.  It took me about 3 weeks of practice after 

Depends.  I got the hang of RS-10 pretty much on the first pass.  While I
didn't have any Elmers on the birds then, I did do a lot of reading before I
got on the air.  The  full duplex nature of satellites helps a lot.  My
current setup is harder to operate, as the VFO locks as soon as I hit
transmit!  That means every few seconds, I have to unkey and QSY up the band
a little to keep the uplink in the right place...

> mode radio as I eventually did.  I'm firmly convinced SSB is 
> not a good 
> entry level experience,  but since I don't have 10M 
> capability myself I'm 
> only guessing that 10M doppler is about the same as 2m 
> doppler. Maybe it 
> isn't.

Doppler is proportional to frequency, so 10m Doppler is much less
significant than 2m Doppler.
> 
> The other objection is HF antennas are huge by today's entry 
> level housing 
> standards.  If you live in an apartment, condo or townhouse, 
> you will be 
> lucky to have a 3 meter wide balcony. Mine is 3.5m x 3.5m, 
> but still not 
> big enough to hide an efficient 10M HF antenna.  I'm lucky to 

I could hear the RS birds on a 2' rubber duck!  My bigger issue was noise on
the downlink from the local environment, which bigger antennas didn't solve
(they just picked up more noise as well as signal :( ).

What other creative ideas might be possible?  Well, with on board DSP
(RUDAK, etc), transponders that configure themselves, depending on where
they are (done my time, GPS or coded control beacons, or manually), so that
over the US, you may have a Mode B SSB transponder, and when it comes over
here, you might have Mode B FM, or something like 2m/70cm FM up, 10m SSB
down, then the 2m input shutting down when the bird gets too close to
Asia...

Just a few thoughts...

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