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Re: Mobile/Portable Satellite Operations



Hi Jason,
Sounds like you're having fun and that's the point of any hobby isn' it? I 
got interested by listening to AO-51 on my dual band mobile. I've yet to 
make a contact yet  although I was lucky enough to convince my XYL to allow 
me to buy a HF/SAT radio after we sold our  gas guzzling speedboat but I'm 
still in the process of working out the rest of my setup and building 
antennas. I agree with not being to afford HEO's. I've got 10 watts of 
1.2ghz RF here but the feedline  to get it to the antenna  and mast mounted 
amps and preamps are beyond my means so it  isn't just the radio expense. 
Ahh well, maybe in the future.
 Anyway, after I get my base set  up then I'll start working on my mobile! 
Sounds like you got a great system worked out.
73,
Michael, W4HIJ
----- Original Message ----- 
From: "Jason Hitesman" <jradio@hitesman.com>
To: <amsat-bb@amsat.org>
Sent: Tuesday, October 04, 2005 7:24 PM
Subject: Re: [amsat-bb] Mobile/Portable Satellite Operations


> John W Lee wrote:
>
>> Unfortunately when the "newer" birds came along, things did not get
>> better they got worse due to the weak downlink signals.  Working mobile 
>> on AO-51 and
>> SO-50 is not so easy.  So don't be disappointed if you're not hearing too 
>> well
>> on your small
>> antennas.  That's just the way it is these days.
>
> I'm fairly new to sats but I've found quite the opposite.  I've been 
> licensed since I got my novice in 3rd grade back in the early 80's 
> followed shortly by a real "tech" (now tech plus) and finally last year 
> got around to upgrading to General mainly because after learning about 
> Echo and the FM sats my interested in radio was rekindled enough to make 
> me want to finally get active on HF with the old FT-747 my dad replaced 
> with a shiny new Icom 756PROII.
>
> I found out about FM sats just a week before Echo launched.  When it came 
> on I listened to the first few passes with nothimg more than a Alinco 
> DJ-C5t and it's stock antenna which was even broken at the time!
>
> I was amazed that I was able to hear anything!  It wasn't much...not 
> enough I'd try to work any of the stations I could hear...but it was 
> enough to get me genuinely interested.  I also tried listening to SO-50 
> and AO-27 but could barely hear anything on SO-50 and AO-27 was just 
> whispers down in the noise and only on real high passes.
>
> Still it was enough to get me looking for a more capable dual band rig and 
> finally early this spring I picked up a used TM-733 and built myself a 
> handheld yagi.  With the 5/8 whip on my truck and the Yagi built from some 
> scrap PVC and house wire following K5OE's plans I started making contacts 
> fairly easily with just 10watts of uplink.
>
> That's still my prefered setup since it's easy to work.  I can set the 733 
> to xmit on VHF but leave the up/down buttons to tune the UHF VFO so with 
> one hand I can work the mic and tune my downlink while I aim the antenna 
> with the other.  For logging I picked up a cheap olympus voice recorder 
> that I Tee off the speaker connection with the other side going to my 
> headphones.   I got the TM for $150, built the antenna literally out of 
> trash, and used my existing VHF whip which I only paid $25 when I got it. 
> The voice recorder was $60 but only because I wanted one with USB download 
> so I could archive things...the $30 one would work just as well.  So for 
> right around $200 starting from nothing a sat station can be put together 
> for working the FM birds.
>
> With my little 3 element Yagi I can hear AO-27, SO-50 and AO-51 full 
> quieting just as clear as my local 440 repeater.  But AO-51 is always the 
> easiest to hear and is nice and clear.  27 and 50 I never hear as clear.
>
> Of course all this got me intersted in more.  I can't afford the radios to 
> work any of the SSB birds or HEO's if there were any.  But I can try to 
> make my current setup easier to use so I didn't have to run outside and 
> point antennas.
>
> I built an eggbeater but without a pre-amp it's next to useless.  Will be 
> solving that soon ;)  I can hear bits and pieces of QSO's on 27 and 51 
> with the Egg but that's about it, nothing workable.  Maybe with the 
> pre-amp it will change but I suspect a rotator is in my future and another 
> Yagi.
>
> In the meantime I upgraded my Yagi to a four element build off Jerry 
> Clement (VE6AB)'s design.  I made it out of more sturdy materials and 
> built it to disassamble and store within itself.  Cost me less than $20 
> even using all new materials.  I also picked up a used FT-470 HT (since I 
> already have 3 FT-23R's and can share battery packs and speaker-mic.) 
> pretty cheap and the past month I've been having an absolute blast making 
> handheld contacts on 27,50 and 51.
>
> Surprisingly I use even less power and an old abused AEA collapsable whip 
> for the uplink (stuck off my diplexer) and can manage to get into all 
> three stats on most passes with that.  Yeah I get stepped on 
> sometimes..but overall it's a lot of fun...and just amazing to me what a 
> minimal antenna and 5watts of power can do!
>
> I still use the voice recorder and then transcribe into my log after, 
> makes things a LOT easier.  I did have a small impedance mismatch on the 
> recorder but a little audio transformer fixed that right up.
>
> Photos of my handheld setup are here:
> http://jhitesma.smugmug.com/gallery/811690
>
> Believe it or not that jumble is actually organized well enough that I can 
> have it unpacked and on the air in less than 5 minutes.
>
> For tracking if I'm just going out for an evening I program the calendar 
> in my cell phone to warn me 5 minutes before AOS and use a name that 
> indicates the compas point the sat will rise near, what the max elevation 
> will be and where it will set.  something like "51-SSW/64/N" would mean 
> "AO-51 rising from the south/southwest going up to 64 degrees and setting 
> to the north"  From that I know generally where to aim and just go by ear 
> as I adjust my antenna for the rest.
>
> If I'll be out for a weekend I use Orbitron to print out a set of passes 
> with AOS/max/LOS times.  Used that to make nearly half a dozen contacts 
> form the middle of the desert this past weekend.  (though I still haven't 
> had time to transcribe my logs of those passes.)
>
> If it wasn't for FM sats I wouldn't have been interested at all and would 
> never have become an AMSAT member.  I probably would still have my license 
> sitting in my wallet collecting dust too.  But now instead I've become 
> active on HF again and in the past year made more contacts than I did in 
> the past decade, I've also joined a radio organization for the first time 
> in over 15 years because I feel AMSAT is doing some truely interesting 
> stuff.
>
> HEO's sound real neat.  And I'd love to work some.  But frankly the cost 
> of entry to play that game is just too high.  Between the antenna and 
> radio requirements it's just not something I can afford and therefore 
> holds little or no interest for me.  Even the LEO SSB sats are out of my 
> reach at this time and for the forseable future due to equipment 
> requirements.
>
> The big problems are things like pre-amps and downconverters aren't cheap. 
> And all-mode UHF/VHF radios just aren't that common or affordable. 
> Needing one or the other is bad enough but needing both is quite a burden 
> on my wallet for equipment that's really only usefull to me for satelite 
> work.  And given that satelites always have a finite lifespan with lots of 
> risks associated with making them live long lives...it's just too much of 
> a gamble for me to invest in.
>
> Though I am keeping my eyes and ears open for a deal on a VHF/UHF all-mode 
> and I do have a 2.4Ghz downconverter I'm working on so who knows...maybe 
> my budget and Eagles budgets will line up at the right time...maybe not.
>
> Either way I'm not too concerned as the FM LEO's are still holding my 
> interest just fine.
>
> ----
> Jason Hitesman
> N8INJ
> jason@hitesman.com
----
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