Amateur radio?
The question wether the standard IEEE 802.11b is amateur radio or not arises. Well, it both is and isn't.
As long as the equipment is used with its original power settings and antennas it is, but if the power is raised above 100 mW (i.e. 20 dBm) it is avantageous to be a radio amateur - except in Sweden.
Are there any IEEE 802.11b stations near you?
Read on about the access point ap.sm6vyf.ampr.org and the gateway gw.sm6vyf.ampr.org. There are also some relevant links and a suggestion on how to identify a station, ping-id, which is my preferred way of identifying.
ap.sm6vyf.ampr.org
As access point a D-Link DWL 900 AP+ is used. As can be seen in the links below this access point can be modified for various needs.
A big drawback is that it has to be configured using a web interface that is dependent of javascript...
I've made a small hack in Perl that can be used for communicating with the access point.
Since the access point doesn't like it too cold or humid (Temperature: -10°C to 55°C / Humidity: 5%-95%, non-condensing), which it is in the real world, it has to stay indoors, just above the balcony door.
The following settings are used for the access point:
- Channel: 5 (2432 MHz med 22 MHz bandbredd)
-
SSID: hsmm
-
MAC-address: 00:40:05:55:F5:CC
-
WEP: No encryption - of course.
Some data for the DHCP server (more about gw.sm6vyf.ampr.org/44.140.200.10 below):
- broadcast-address: 44.140.200.15
- subnet-mask: 44.140.200.248
An external antenna, Comet GP-24, is now in place - 15 dBi. It took 3 kg aluminium, two U-bolts, some screws and plugs plus lots of straps to get it into place and now it's up there. Will it survive the autumn storms?
Visitors of these pages knows, that the view from the antenna can be looked upon.
Two things keep me from running with higher power. First, the swedish national post and telecom agency, PTS, has decided (PTSFS 2001:4) that for this band, a ten thousand of the power compared to the adjacent bands will do. Second, amplifiers, e.g. SSB Electronic Model WL-2400 A, are expensive.
In the meanwhile I'll just have to wait for the first QSO...
gw.sm6vyf.ampr.org
This computer, Dell OptiPlex 5133 GMT - 133 MHz / 32 Mbyte / 1 Gbyte (bought for USD 10 at Boeing Surplus 2002), is running SuSE Linux 8.2. It is configured as a link between sm6vyfnet.sm6vyf.ampr.org and the rest of the net-44.ampr.org through a tunnel to rupert.sk0bu.ampr.org.
Using a DHCP server the connecting station is assigned an IP number. Through DHCP a name server (DNS) is set, in this case gw.sm6vyf.ampr.org since no other is available through sm6vyfnet.sm6vyf.ampr.org. To keep non-amateurs out the MAC addressen of the connecting station is checked. Only those MAC-addresses that are known to the DHCP server are offered IP numbers.
So if you want to try you'll have to contakt me to get on to the list.
The computer is also running a web server (AllegroServe) to offer something to look at (the contents are, more or less, the same as at http://gatugarden.com/sm6vyf/). There's a special page about the server installation.
ID using ping
How to identify a station using ping, cf. n9zia ping id. I've extended n9zia's script some with the following result:
#!/bin/sh
# A.S. 16.IX.03
DEST="44.140.200.10"
IDSTR="sm6vyf.ampr.org amatörradiostation"
let L=${#IDSTR}
let T=8+L
#text to hex (best way?)
DATA=`echo $IDSTR | od -tx1 -N $L -w$L | head -n1 | cut -d' ' -f2- | tr -d ' '`
while true
do
/bin/ping -c 1 -s $T -p $DATA $DEST >/dev/null
sleep 600
done
If cron is preffered, remove the while loop and add the following using crontab -e:
MAILTO=""
-*/10 * * * * /pathto/pingid.sh
QST article April 2003