THE LA2QAA PORTABLE AO-7 STATION.
The portable station comprises the following items of equipment.
FT-290RII receiver.
0.4dB preamp
Headphones.
FT-790 700mW transmitter + mic
Homebrew 10w amplifier
Homebrew keyer and paddle
5 amp gel battery
Assorted cables
Split boom Arrow aerial - (diplexer removed)
Lightweight collapsible tripod camera
Shopping trolley/back-pack - (with handle & wheels)
Noka phone with SATme tracking software.
Bluetooth GPS - (position)
Orienteering compass
Creative Zen MP3 recorder
Everything packs down into the shopping trolley and takes approximately 5
minutes to set up.
There are several photos included in this short article. The rigs are self
explanatory, they are light and easy to operate with gloves on in the winter
months. The aerial is the split boom Arrow with 7 elements on70cm and 3
elements on 2m. Remember, this is a QRP station for a QRP satellite so you
don't want to be lugging
around too much aluminium. The lightweight collapsible camera tripod is very
handy for mounting the aerial for when your arms get tired from waving your
pointy stick at the sky.
FT290Mk2(top) and FT790R (bottom), plus tripod.
The Nokia phone is essential since it has the SATme tracking program
installed. Remember to update the keps before you hit the road. The Holux
Bluetooth GPS receiver is self explanatory. If you move a fair distance from
a previously set operating position you'll want to know where you are, and
the GPS will tell you
- as well as give you the precise time for your tracking program.
The electronic keyer is built into a small spice box. Note the paddles
...they're *RIPPED* out of a standard joystick and perform excellently
...OK, not 'Bencher' standard but almost !!.
Keyer and paddle.
A boom mic attached to your headset, with a VOX could be an advantage too.
The attenuator is a small homebrew -10dB item for the RA30H4047M 'brick'amplifier
which is built into an aluminium lunchbox with forced air cooling from a
small computer fan - 'heavy' heatsink material was deemed to be too clumsy
for portable operation. The PA runs at 10woutput to keep it in the
'official' QRP limit.
PA, GPS and Attenuator
The 5 amp battery is a gel type so it doesn't matter if it rolls over in
your backpack/trolley.
Needless to say, it's a great advantage when operating portable to use
headphones. The signals *WILL* be weaker than those from the average base
station so I would appreciated if people also try to work the weakones as
well as the exotic DX.
Remember, Frei Island is IOTA-EU-36 and anyone working me portable will
receive a special AO-7 anniversary QSL card on request.
Frei is surrounded by mountains except to my north so being portable is a
definite advantage when the bird is coming up from my south.
73 John. <la2qaa@amsat.org __._,_.___