[amsat-bb] Re: Active FM Sats

John Geiger aa5jg at fidmail.com
Tue Jul 5 09:10:45 PDT 2011


Belcom used to make (and might still make) all mode HTs that cover a wide
variety of bands.  Santec imported one as the LS202 in the 80s, it was an
all mode 2 meter HT.  I found one at a hamfest with 2 new battery packs a
couple of years ago for $80!  AEA imported the 10 meter version (and the 6m
version but that doesn't help with the satellites) back in the 80s, calling
it the "DX Handy".  Around 2000 Eagle made the Eagle 454 Spitfire which was
a 10 meter all mode HT (mainly aimed at the CB and Freeband crowd), and
another company has recently started marketing a 10 meter all mode HT
again.  Belcom also made a 70cm all mode HT.

So, there are rigs out there in HT format that will work on the linear
satellites, now the job is to find them!

I have been waiting to comment on early threads on this post as well.  While
the linear satellites do hold more possibilities, they are more expensive to
get on, and unfortunately in the States, there just isnt' that much activity
on VO52 which is unfortunate since it is a such a great satellite.  The FM
satellites are just cheaper to get started on.

For example:  my FM satellite station consists of

Kenwood TM-251A bought used for $99
Arrow Antennas dualband J Pole bought new for $40
50 foot run of 9913 knock off coax bought new for $38
So, for less than $200 I have a good FM setup.  I already had the power
supply, but if you need to buy a new one, figure $75 or so.

I can do one linear sat right now-AO7 in Mode A-using my Icom 706 original.
I bought the rig for $260, got a Mirage B108 amp for $40, and a 2M9SSB for
$40 (plus the gas and tolls to pick it up).  The light duty rotor  was
already up but it was about $80 new.  The 9913 copy coax was $38.  For the
10 meter downlink I already had a dipole up, but that would cost $30 or so
to build-including coax.  Overall, I got very good prices on this setup, it
would usually cost more.

I give both examples just to show the difference in setup costs.  With my
Icom HF/VHF setup I cannot work Mode B on the satellites, as I don't have a
UHF transmitter (as of yet).

73s John AA5JG

On Tue, Jul 5, 2011 at 10:43 AM, Patrick STODDARD (WD9EWK/VA7EWK) <
amsat-bb at wd9ewk.net> wrote:

> Hi!
>
> > Show me an all-mode HT that retails for the same sort of price and is the
> > same sort of size as an FM HT and I might be interested.  Otherwise, to
> > get UHF and VHF SSB I'm stuck with an inconveniently large radio which
> > is only really useful for the twenty minutes a day that a satellite is
> > overhead.
>
> An all-mode HT.... doesn't exist at this time.  Probably the closest you
> get
> in an HT would be a TH-F6/TH-F7 with its all-mode receiver, but still an FM
> transmitter.  You could attempt transmitting CW by keying that transmitter,
> but it's not ideal with the 5 kHz tuning steps at FM on that radio (SSB
> tuning steps on a TH-F6/TH-F7 can go as small as 33 Hz) and no
> provision for computer control.  Otherwise, an FT-817 gets close to the
> HT size, is an all-mode transceiver at HF and 6m as well as 2m and
> 70cm, and would qualify as a radio that can be used more than "twenty
> minutes a day that a satellite is overhead."  It does cost more than an
> FM HT, but FT-817s should be available on the secondhand market
> as they have been in production for a decade.  Even two FT-817s as
> a portable all-mode full-duplex satellite station are not what I - or
> many - would consider "inconveniently large".  If you prefer computer
> control, the 817s have Yaesu's CAT port to allow for that.
>
> > Not to mention the difficulty involved in tuning the radio and aiming the
> > antenna.  Doesn't the Doppler shift mean you need to constantly
> > retune?  How do you manage to do that, key the mike and point the
> > aerial, *and* have enough brainpower left to make a contact?
>
> You are having to make minor adjustments to your frequency - or
> frequencies - when working SSB or CW via satellite.  If you follow the
> so-called One True Rule, you're making the adjustments to one of
> the two frequencies (usually the higher of the two frequencies).
> Everyone had to work SSB/CW via satellite this way in the past,
> before the advent of computer-controlled stations, and it is still an
> option today even if some (many?) discourage it.
>
> If you've worked FM satellites, you already know about the "key the
> mike and point the aerial" part.  Then just focus on the QSO in
> progress.  Don't try to remember everyone you worked - leave that
> on an audio recorder, or recorder app for a mobile phone or iPod
> type of device or laptop/netbook, and play it back later to update
> your log.
>
> Pedro EB4DKA has posted a lot of useful information for working
> SSB via satellite.  I read the writeups and watched the videos as I
> started out on the SSB birds.  I don't operate using a mobile setup
> like Pedro does, but with one directional antenna (an Elk 2m/70cm
> log periodic) through a diplexer to my two-radio setup.  I've
> uploaded some videos working those satellites at:
>
> http://www.youtube.com/va7ewk
>
> I used both of my FT-817NDs on the SSB passes shown in these
> videos, but on occasion swap out the 817 I use as the receiver
> and put my TH-F6A in its place.
>
> 73!
>
>
>
>
>
>
> Patrick WD9EWK/VA7EWK
> http://www.wd9ewk.net/
>
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