[amsat-bb] AO-7 portable.

John Hackett archie.hackett at hotmail.com
Sat Jun 14 10:39:45 PDT 2008



The portable station comprises the following items of equipment.

FT-290RII receiver.
0.4dB preamp
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 collapsable 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 explanitory, they are light and easy to operate with gloves on in the winter months. The aerial is the split boom Arrow with 7 elements on 70cm 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 lighweight collapsable camera tripod is very handy for mounting the aerial for when your arms get tired from waving your pointy stick at the sky.

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 explanitory. 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 exellently ... OK, not 'Bencher' standard but almost !!.

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 10w output to keep it in the 'official' QRP limit.

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 geat 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 weak ones as well as the exotic DX.

Remember, Frei Island is IOTA-EU-36 and anyone working me portable will receive a special AO-7 anniversay QSL card on request.

Frei is surrounded by mountains except to my north so being portable is a definate advantage when the bird is coming up from my south.

73 John.   <la2qaa at amsat.org> 

More information about the AMSAT-BB mailing list