News archive July 2008 - Koos van den Hout

Wardriving results 10 June - 30 July: 1615 new networks with GPS locations. Not much happening due to the holiday because I'm not taking the wardriving box on a cycling holiday.

The apple tree in our back garden is so loaded with apples the branches are bending under the weight. Not breaking (yet). Looks like a lot of apples will be available in a few weeks.

The apple-tree in our garden heavy with apples.

I decided to start monitoring the electricity usage in the house. Using 1-wire sounds the most logical to me as I am already using that to monitor temperatures. I found a description by Jon00 using a MK120 Velleman Kit which sounds quite compatible with my level of electronics knowledge and my budget. So I went to the local electronics shop, Radio Centrum and bought the Velleman MK120. I asked about a 1-wire counter but they don't sell 1-wire equipment (yet?). Well, a counter is something I can order from Hobby boards. Probably together with some other 1-wire stuff to make it an interesting order.

Hot, hot: temperature under the roof (sensor 2)

Jul 27 18:43:23 Sensor 2 C: 35.62

And we're back from vacation! We cycled around Denmark for almost three weeks. A total of 1080 Kilometers on our recumbents from København to Århus along a number of the Danish islands and Jylland. We used trains from Utrecht to København and from Århus to København back to Utrecht. The intercitynightline is nice for getting from Utrecht to København in one go. It just takes a big detour of Germany. The intercitynightline and the Danish trains have no problems at all with recumbents. We saw a lot in Denmark, including a visit to Legoland in Billund and the Elmuseet. The weather was ok although we had a number of rainy days. We stayed in hostels, bed and breakfast and a few hotels.

More ntp fun: I now have multicast ntp time working and documented. With the listed ntp key clients can use the multicasted network time from ntp.cs.uu.nl. The outgoing timestamps look like this in tcpdump:

14:45:06.821419 IP (tos 0x0, ttl  30, id 6195, offset 0, flags [none], proto 17, length: 96) 131.211.84.189.ntp > 224.0.1.1.ntp: NTPv4, length 68
        Broadcast, Leap indicator:  (0), Stratum 2, poll 6s, precision -19
        Root Delay: 0.000000, Root dispersion: 0.001724, Reference-ID: 127.127.22.0
          Reference Timestamp:  3424077852.817587474 (2008/07/03 14:44:12)
          Originator Timestamp: 0.000000000
          Receive Timestamp:    0.000000000
          Transmit Timestamp:   3424077906.819248263 (2008/07/03 14:45:06)
            Originator - Receive Timestamp:  0.000000000
            Originator - Transmit Timestamp: 3424077906.819248263 (2008/07/03 14:45:06)

I also see multicasted time from 192.36.143.151 (time2.stupi.se) but I can't find a key for it.

A new peak in ntpd traffic on ntp.cs.uu.nl : 1986 packets/second. From a very limited peek at the IP numbers it seems the 'friends' at turkish telecom were quite interested in the correct time.

Bericht in het Algemeen Dagblad vandaag: Slimme energiemeter meet privégegevens [link verlopen]. Precies de reden waarom ik veel statistieken thuis afscherm en alleen sensors laat zien die minimaal verband hebben met aanwezigheid van personen. Aan het wireless verkeer is veel nauwkeuriger te zien of er mensen thuis zijn, die gegevens zijn dus niet publiek en worden niet buiten het huis opgeslagen. Ik wil pas een 'slimme' energiemeter als ik deze zelf kan uitlezen met rrdtool en ik zeker weet dat de gegevens niet buitenshuis op te vragen zijn.

Daarnaast is er nog de vraag hoe deze 'slimme' energiemeter gaat communiceren met de leverancier. De kans is ruim aanwezig dat dit via PLC (powerline communications) gaat, want er ligt toch al een (electriciteits)draad tussen de meter en de netbeheerder. PLC kan storingen veroorzaken voor radio-amateurs, deze houden de ontwikkeling rond de 'slimme' energiemeter dus ook scherp in de gaten.