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Re: Beginner birds




Hi Wayne,

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.

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 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 migrating up from 
being very good at FM dispite all the encouragement and help I got from 
experienced Elmers like N7EQF and KE6OAG, and there were still times I was 
in tears. I don't think someone just starting out would have the patience - 
I wouldn't have, and I probably wouldn't have invested the cash for an all 
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.

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 have a small 
(32")  5ele 2m beam and a small (39") 10ele 70cm beam that I can stick in 
an umbrella stand and rotate by hand.  And forget putting antennas in the 
house - most modern construction has so much metal it's like living in a 
birdcage.  RF isn't coming in very well at all.  The entry level steerable 
gain antenna for working FM birds is an Arrow or other small handheld gain 
antenna.  You don't need a beam, rotator and large mast, you just go out on 
the balcony with an HT and handheld antenna and "shoot the bird."

Your "super Echo" would probably be sufficient (divide a mid-continent 
UO-14 pass by 10 and it's now manageable.) However, once it becomes popular 
it would be crowded again, though I think things like this have a habit of 
self-regulating.  We are really only talking mid-continent since coastal 
passes are generally more quiet.  Divide them by ten and they would be 
almost empty. But I'd wager everyone would crowd the busiest channels just 
like people crowd the middle of the passband on SSBs, wait in line for 
hours on opening night of popular movies, and stand outside popular clubs 
and restaurants. It's human nature.

0.02  & 73,

Emily





At 11:33 AM 7/22/2003 -0500, you wrote:
>Emily wrote:
>
>I  don't see how 10M will do as much as 2m/70cm or 70cm/23cm for attracting
>new blood.  If you want young blood, go for something the techs can work
>right away.
>
>Wayne replies:
>
>U.S. Techs are permitted to work every ham transponder ever launched, 
>except RS-12 "Mode K" which required an Advanced license to use the 15m 
>uplink.    Mode A satellites use a 10m downlink, and everybody is 
>permitted receive on 10m.  But of course you can't operate a Mode A linear 
>transponder with an FM-only radio, except to make slow chirpy CW contacts 
>(and most techs don't know the code).  Techs would need a 2m multi-mode 
>radio and a SSB HF receiver to operate mode A linear transponders.  The 
>VHF multi-mode radio would be a good building block for getting on the 
>"higher" satellites.  An HF receiver isn't particularly useful for other 
>satellites, except when used with converters.  But a VHF/UHF FM radio is 
>even less useful for the "higher" satellites.
>
>RS-10 (Mode A) was the first ham satellite I ever heard and the first ham 
>satellite I ever made a 2-way contact on.  One neat thing about Mode A 
>satellites is that a large percentage of hams already have a suitable 
>radio and antenna to LISTEN to the 10m downlink just to get an idea of 
>what it's like to operate satellites.  I first heard RS-10 before I even 
>had a tracking program, listening on my HF transceiver with a multi-band 
>HF vertical antenna.  I just tuned up there a few times until I happened 
>to hear a pass.  Unfortunately, the typical entry-level ham equipment has 
>changed over the years.  10 years ago, entry level was typically a 
>second-hand HF rig and an HF vertical or trap dipole.  Nowadays it's a 
>VHF/UHF FM mobile rig and a dual-band collinear vertical (or even just a 
>dual-band HT).  But a new ham can get a used HF transceiver and put up a 
>10m inverted Vee for less than $200.  Then the new ham could get a taste 
>of HF SSB and satellite SSB if we had a Mode A satell!
>  ite.
>
>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.
>
>Wayne Estes W9AE
>Mundelein, IL, USA
>----
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