News archive February 2014 - Koos van den Hout

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2014-02-28 (L-269: Logbook Very timely class today for Terry and myself at JAXA. Just a few hours ago on ISS a ...) 6 years ago
Google+Koos van den Hout : Log of a cubesat launch from ISS, interesting for this community. Spotted by +fan tai.
2014-02-26 (One of our cats enjoying the warmth of the dishwasher.) 6 years ago
Google+Koos van den Hout : One of our cats enjoying the warmth of the dishwasher.
2014-02-26 Linux wireless regulatory domain information 6 years ago
I noticed in the logs of the weather station computer ritchie:
[770336.506717] cfg80211: Calling CRDA to update world regulatory domain
[770336.906545] cfg80211: World regulatory domain updated:
[770336.906567] cfg80211:   (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[770336.906585] cfg80211:   (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[770336.906602] cfg80211:   (2457000 KHz - 2482000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[770336.906619] cfg80211:   (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[770336.906635] cfg80211:   (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[770336.906652] cfg80211:   (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
But I'm in a specific country (the Netherlands) although the access-point is old enough to not transmit the regulatory domain information. I found out I can update the default in the client using:
root@ritchie:~# iw reg get
country 00: DFS-UNSET
        (2402 - 2472 @ 40), (3, 20)
        (2457 - 2482 @ 40), (3, 20), NO-IR
        (2474 - 2494 @ 20), (3, 20), NO-OFDM, NO-IR
        (5170 - 5250 @ 40), (3, 20), NO-IR
        (5735 - 5835 @ 40), (3, 20), NO-IR
root@ritchie:~# iw reg set NL
root@ritchie:~# iw reg get
country NL: DFS-UNSET
        (2402 - 2482 @ 40), (N/A, 20)
        (5170 - 5250 @ 40), (N/A, 20), NO-OUTDOOR
        (5250 - 5330 @ 40), (N/A, 20), NO-OUTDOOR, DFS
        (5490 - 5710 @ 40), (N/A, 27), DFS
        (57240 - 65880 @ 2160), (N/A, 40), NO-OUTDOOR
This changes maximum power, bandwidth and frequency ranges. And indeed in dmesg:
[770977.623611] cfg80211: Calling CRDA for country: NL
[770977.715887] cfg80211: Regulatory domain changed to country: NL
[770977.715909] cfg80211:   (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[770977.715926] cfg80211:   (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[770977.715941] cfg80211:   (5170000 KHz - 5250000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[770977.715957] cfg80211:   (5250000 KHz - 5330000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[770977.715972] cfg80211:   (5490000 KHz - 5710000 KHz @ 40000 KHz), (N/A, 2700 mBm)
[770977.715988] cfg80211:   (57240000 KHz - 65880000 KHz @ 2160000 KHz), (N/A, 4000 mBm)
Now I wonder about the flags... NO-IR = no initiating radiation the device may not transmit on a frequency until it has received beacons on the frequency. DFS = Dynamic Frequency Selection which is mainly avoiding collision on the 5 GHz wireless band with weather radars.

More information about this subject at Regulatory - Linux Wireless.

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2014-02-21 (I really like the size difference between the dumb terminal and the host computer. And the RaspberryPi...) 6 years ago
Google+Koos van den Hout : I really like the size difference between the dumb terminal and the host computer. And the RaspberryPi is probably a lot more powerful than what a dinosaur pen was filled with in the days an ADM3A was the standard.
2014-02-21 (#) 6 years ago
I almost started to digres in my last post getting an APRS report out using an android device, aprsdroid and a wouxun radio about the privacy implications but decided to separate that issue. It works, and I am not going to invest in it.

APRS is nice, but for me it has privacy implications: it reports my position in real-time which is more than I want to share with the world, even as an amateur radio experiment. I know there are people who will post their bicycling tours or runs on-line as they happen but I don't like publishing my wereabouts, especially not in (near) real-time. Enough people can browse the mobile telecom location registers as it is.

So I think I'll leave the APRS location experiments at this and I'll go look at other amateur radio stuff. There is enough to play with!

I know APRS is bigger than just reporting location. Getting my weatherstation in Utrecht Overvecht to report weather to the APRS citizen weather observer program is on my wishlist.

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2014-02-20 (#) 6 years ago
Again playing a bit with APRS and aprsdroid. No luck with using a 3.5mm to 3.5mm audio cable, the vox on the wouxun KG-UVD1P does not trigger at all. I did test with the audio from aprsdroid near the microphone of my laptop and decoding it with multimon, and that works:
AFSK1200: fm PD4KH-7 to APDR12-0 via WIDE1-1 UI^ pid=F0
=5206.  N/00507.  E$/A=000162 http://pd4kh.idefix.net/
pd4kh on aprs.fi display The 'audio through the air' method works with the radio right next to the internal speaker of the android device: with some fiddling of audio settings on the android device and vox settings on the wouxun I can send out a position report and it shows up on the aprs network! Wouxon vox level at 5, audio output type "music", audio level medium.

The pink square is because I don't give out a very precise location on purpose.

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2014-02-18 (#) 6 years ago
After getting the gps running in the shed I noticed a bit of variation in the output location as logged from the NMEA $GPGGA strings in the clockstats file. And reading Tom van Baak testing the MG1613S GPS Receiver noting the variation in location made me decide to do a bit of plotting of location on my own. As Tom notes, plotting distance in meters gives a better idea of scale. So I wrote a bit of perl to massage the lat/long pairs into X/Y meters from a starting point. I was lazy: I used the first measurement as starting point. The resulting X/Y pairs are graphed using gnuplot.

Update: I'm a security specialist, not a programmer: I found some errors in the routines that convert output from the GPS to degrees to meters. Fixed them, so the first graph has been redrawn using data from 17 and 18 Februari.

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2014-02-16 (#) 6 years ago
Since the old gpskit gps was showing problems in ntp tests earlier I decided now that the weatherstation computer is up and running on the alix.1c board to try a different gps unit: The Holux GR-213 GPS I still have from earlier wardriving. holux 213 gps

Not much of a succes sofar. First the GPS did not get a lock at all. I was expecting a delay in acquiring a lock since it hadn't been used in over a year but after a day and a half it still wasn't locking. So I moved it a bit which led to a lock (blinking led). But ntpd was still not using the GPS_NMEA driver. When I had time to have more of a look than just the graphs at NTP server ritchie.idefix.net stats I noticed ntpd was still seeing GPS_NMEA as a falseticker. Which is about right, when I look at the peer stats the GPS_NMEA clock has an offset of about 500 milliseconds(!!) compared to the rest.

To my best knowledge I can find the right offset with 'enable calibrate'. But documentation is very minimal on this matter: Reference clock drivers - ntp 4.0.99k documentation has:
The recommended procedure is to enable the function, let it run for an hour or so, then edit the configuration file using the time1 values displayed by the ntpq utility and clockvar command.
With 'enable calibrate' on I see after a long run:
ntpq> peer
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
+greenblatt.idef 131.211.8.244    2 u  137  512  377    1.012    1.780  87.722
*metronoom.dmz.c .PPS.            1 u  166  512  377   18.297   -1.207  46.401
+auth1.xs4all.nl 193.67.79.202    2 u  119  512  377   16.604   -1.104  27.267
xGPS_NMEA(0)     .GPS.            0 l    4   16  377    0.000  -529.94   3.286
ntpq> clockvar
associd=0 status=0000 , no events, clk_unspec,
device="NMEA GPS Clock",
timecode="$GPGGA,210752.000,5206.6230,N,00507.0976,E,1,06,1.5,-0.1,M,47.1,M,,0000*7F",
poll=762, noreply=0, badformat=0, baddata=0, fudgetime1=0.000, stratum=0,
refid=GPS, flags=0
So even after running for a long time with clearly an offset between the other clocks and the reference clock there is no change in the suggestion for the time1 factor, still showing 0.000.

Remarks in [ntp:questions] enable calibrate? suggest 'enable calibrate' will only work when there is a PPS signal available, and confirm the lack of documentation and samples I found.

The Holux GR-213 also does not have a PPS signal to the outside at all, so I can't use a PPS signal anyway.

Update: Some sleep, thinking and reading later: first of all, time1 is the PPS time offset and time2 is the gps message offset, found by reading ntpd documentation Generic NMEA GPS driver.

So I started looking for the right offset with the 127.127.20.0 driver in noselect mode. After some testing I found a reasonable answer with:
# GPS as time source without pps
server 127.127.20.0 minpoll 1 maxpoll 4
fudge 127.127.20.0 time2 +0.544
And now things look better:
ntpq> peer
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
+greenblatt.idef 131.211.8.244    2 u    2   64   77    0.956   -2.252  41.400
*metronoom.dmz.c .PPS.            1 u    5   64   77   17.921   -2.236   1.190
-auth1.xs4all.nl 193.67.79.202    2 u    3   64   77   16.254   -2.750   0.880
+GPS_NMEA(0)     .GPS.            0 l    2    8  377    0.000   -5.916   1.100

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2014-02-12 (#) 6 years ago
I decided to try aprsdroid on my android device. First and easiest should be to select the option AFSK via Speaker/Mic and I hoped it would work when the speaker and microphone of the portable radio are near the microphone and speaker of the android device. No luck: no transmitted APRS packet was found via aprs.fi call PD4KH and no incoming packet was decoded. I guess there was too much distortion and interference. I looked at the aprsdroid settings a lot since I noticed outgoing audio seems to be fixed at the highest volume, which can also be an issue.

In the video Get Started with APRS for only $30! - youtube.com video a simple cable from the android device to the radio is used, so it can be done.

Going for a solution like an Mobilinkd is more expensive, but maybe interesting in the long run when I want to do more with APRS. For now, an interim solution would be nice: building the right cable to get audio from the radio to the android device and back. I found the specs for such a cable at iPhone / Baofeng interface bouw en schema - PA4TW which can be adjusted for the android device and Wouxun. And PA4TW has used it for APRS in Aprs via porto en iPhone - PA4TW.

Old analog telephone equipment can be a source of 600 ohm 1:1 transformers, so I guess some old equipment will have to donate those when I go for such a cable.

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2014-02-11 (Interesting SDR article.) 6 years ago
Google+Koos van den Hout : Interesting article found by +K7AGE
2014-02-06 (#) 6 years ago
The webcam image at webcam.idefix.net is getting popular at the moment due to the use by nedWeer.nl peaking at 0.5 requests/second.

Since the image is imported from a different server in a proxying setup this was causing quite some traffic on my adsl line. The image doesn't update every second, so I had a look into caching possibilities with apache 2.2. I wanted to use the memory cache for just this one object but I started with the disk cache because it's easier to debug and see the files on disk. This didn't work, and I could not figure out why. I followed the instructions found in apache2 - Apache Reverse Caching Proxy - why isn't it caching? - stackoverflow.com but still no caching happening.

I set up a separate virtual server with the logging set to level 'debug' and found the following interesting line in the log:
[Thu Feb 06 16:24:59 2014] [debug] mod_cache.c(370): (12)Cannot allocate memory: cache: Cache provider's store_body failed!
This looked more like a memory cache problem than a disk cache problem. But the memory cache wasn't configured at all. I decided to remove the memory cache support completely and that fixed things with the disk cache. The debug log suddenly had the right messages:
[Thu Feb 06 16:25:59 2014] [debug] mod_cache.c(633): cache: Caching url: /camwindow.jpg
Now the webcam image is cached for 120 seconds. Which saves some traffic on the ADSL line.

Update 2013-02-10: Requests still going at about 0.5 requests/second at busier times. The proxy reduces the impact on ADSL traffic and ping delays.

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2014-02-05 (#) 6 years ago
SIP scanning going on again, probably related to Security advisory: suspected telephone misuse in fritzbox systems. My Internet provider xs4all uses fritz!box devices by default and I already heard about one case of abuse.

The SIP scan in tshark:
Frame 376 (457 bytes on wire, 457 bytes captured)
    Arrival Time: Feb  5, 2014 18:00:07.447662000
    [Time delta from previous captured frame: 36.927214000 seconds]
    [Time delta from previous displayed frame: 0.000000000 seconds]
    [Time since reference or first frame: 6100.139111000 seconds]
    Frame Number: 376
    Frame Length: 457 bytes
    Capture Length: 457 bytes
    [Frame is marked: False]
    [Protocols in frame: sll:ip:udp:sip]
Linux cooked capture
    Packet type: Unicast to us (0)
    Link-layer address type: 512
    Link-layer address length: 0
    Source: <MISSING>
    Protocol: IP (0x0800)
Internet Protocol, Src: 188.138.41.34 (188.138.41.34), Dst: xxx.xxx.xxx.xxx (xxx.xxx.xxx.xxx)
    Version: 4
    Header length: 20 bytes
    Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
        0000 00.. = Differentiated Services Codepoint: Default (0x00)
        .... ..0. = ECN-Capable Transport (ECT): 0
        .... ...0 = ECN-CE: 0
    Total Length: 441
    Identification: 0x0000 (0)
    Flags: 0x04 (Don't Fragment)
        0... = Reserved bit: Not set
        .1.. = Don't fragment: Set
        ..0. = More fragments: Not set
    Fragment offset: 0
    Time to live: 53
    Protocol: UDP (0x11)
    Header checksum: 0x475e [correct]
        [Good: True]
        [Bad : False]
    Source: 188.138.41.34 (188.138.41.34)
    Destination: xxx.xxx.xxx.xxx (xxx.xxx.xxx.xxx)
User Datagram Protocol, Src Port: 5079 (5079), Dst Port: sip (5060)
    Source port: 5079 (5079)
    Destination port: sip (5060)
    Length: 421
    Checksum: 0xc761 [correct]
        [Good Checksum: True]
        [Bad Checksum: False]
Session Initiation Protocol
    Request-Line: OPTIONS sip:100@xxx.xxx.xxx.xxx SIP/2.0
        Method: OPTIONS
        [Resent Packet: False]
    Message Header
        Via: SIP/2.0/UDP 62.75.212.215:5079;branch=z9hG4bK-1039150734;rport
            Transport: UDP
            Sent-by Address: 62.75.212.215
            Sent-by port: 5079
            Branch: z9hG4bK-1039150734
            RPort: rport
        Content-Length: 0
        From: "sipvicious"<sip:100@1.1.1.1>;tag=3532356663346361313363340132393433303934303439
            SIP Display info: "sipvicious"
            SIP from address: sip:100@1.1.1.1
            SIP tag: 3532356663346361313363340132393433303934303439
        Accept: application/sdp
        User-Agent: friendly-scanner
        To: "sipvicious"<sip:100@1.1.1.1>
            SIP Display info: "sipvicious"
            SIP to address: sip:100@1.1.1.1
        Contact: sip:100@62.75.212.215:5079
            Contact Binding: sip:100@62.75.212.215:5079
                URI: sip:100@62.75.212.215:5079\r
                    SIP contact address: sip:100@62.75.212.215:5079\r
        CSeq: 1 OPTIONS
            Sequence Number: 1
            Method: OPTIONS
        Call-ID: 37933976157019277147119
        Max-Forwards: 70
Source IPv4 was 188.138.41.34, Plusserver AG. Interesting pointer at IPv4 address 62.75.212.215, a different IPv4 range at Plusserver AG.

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2014-02-05 (#) 6 years ago
De eerste QSL-kaart is binnen! Van het contact met PD6SHELL een leuk kaartje.

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2014-02-03 (#) 6 years ago
In searching for information about the Alix 1.c bios upgrade I'd like to do I came across mention of flashrom, a command line utility which can do firmware flashing for a lot of systems right from the commandline. No more long downtimes due to being busy with bootable floppies, cd's, usb sticks or slow update programs.

Initially the program gave a warning on ritchie, but with one "I am sure what I am doing" option:
root@ritchie:~# flashrom --programmer=internal:laptop=this_is_not_a_laptop -r oldbios.bin
flashrom v0.9.6.1-r1563 on Linux 3.12-1-486 (i586)
flashrom is free software, get the source code at http://www.flashrom.org

Calibrating delay loop... OK.
========================================================================
WARNING! You may be running flashrom on an unsupported laptop. We could
not detect this for sure because your vendor has not setup the SMBIOS
tables correctly. You can enforce execution by adding
'-p internal:laptop=this_is_not_a_laptop' to the command line, but
please read the following warning if you are not sure.

Laptops, notebooks and netbooks are difficult to support and we
recommend to use the vendor flashing utility. The embedded controller
(EC) in these machines often interacts badly with flashing.
See http://www.flashrom.org/Laptops for details.

If flash is shared with the EC, erase is guaranteed to brick your laptop
and write may brick your laptop.
Read and probe may irritate your EC and cause fan failure, backlight
failure and sudden poweroff.
You have been warned.
========================================================================
Proceeding anyway because user forced us to.
Found chipset "AMD CS5536". Enabling flash write... OK.
WARNING: unexpected second chipset match: "AMD CS5536"
ignoring, please report lspci and board URL to flashrom@flashrom.org
with 'CHIPSET: your board name' in the subject line.
Found SST flash chip "SST49LF040B" (512 kB, LPC) at physical address 0xfff80000.
Reading flash... done.
Checksums for the saved bios file match with the bios image I have from the last upgrade.

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2014-02-03 (#) 6 years ago
I had a closer look at the available PC Engines alix 1.c bios updates and noticed alix0.bin and alix2.bin images in the .zip file. A bit of searching found 3D3 BIOS-Upgrade: Which one is the right file? - PC Engines support forum which lists alix0.bin for alix.1 systems and alix2.bin for alix.3 systems. Should work with the provided sb.com.

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2014-02-02 (#) 6 years ago
The change to the new weatherstation computer also means the powerline network is now gone. And I mean gone, not just disconnected "just in case". The adapters are back in a crate. And this should mean the HF spectrum should look nicer than in my earlier measurements. Future measurements may confirm this.

The weatherstation computer now uses Wi-Fi to talk to the rest of the network. Since the access-point is on the same ground level the signal quality is good and speed is high enough.

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2014-02-02 (#) 6 years ago
Today there was time to change the computer in the shed to ritchie, the alix 1.c based system. The system decided this was a great moment to run into the "system won't boot without monitor present" issue. I found a funny workaround: I disabled the video memory. This does mean the display doesn't work at all, but at least it boots. I'll do a bios reset and upgrade sometime in the future. The PC Engines alix1c product page lists possible problems with a vga boot hang as fixed in a newer bios.

After that the system started working nice, talks to the weather station hardware and Weatherstation Utrecht Overvecht is back up.

This system with a standard power usage of about 5W will be 'greener' than the replaced older PC. There is a free serial port for a gps, but since the gpskit gps was showing strange problems in the ntp server test I decided to take that gps back inside to have a look whether that can be used or I want to search for some other gps unit to have my own home time server. Maybe the wardriving gps unit.

Some sort of plastic container to keep all the electronics together and shielded is also a good idea.

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2014-02-01 (#) 6 years ago
Spammers liegen, zelfs als ze de spammers zijn voor het Algemeen Dagblad:
Vorig seizoen bracht het AD, als partner van Feyenoord, het 'Feyenoord doeboek' uit. U heeft dit doeboek destijds in de webwinkel van het AD besteld.
Het adres waar ze naar mailen heeft zich ooit geregistreerd voor de volkskrant website, meer niet.

Ik vraag me nu wel af met wat voor kwaliteit ze de nieuwsbijlage van hun 'krant' vullen als de afdeling marketing zo omgaat met de waarheid.

Originating IP 146.185.54.163 waar ook geen abuse contact voor te vinden is.

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, reachable as koos+website@idefix.net. PGP encrypted e-mail preferred.

PGP key 5BA9 368B E6F3 34E4 local copy PGP key 5BA9 368B E6F3 34E4 via keyservers pgp key statistics for 0x5BA9368BE6F334E4 Koos van den Hout
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Other webprojects: Camp Wireless, wireless Internet access at campsites, The Virtual Bookcase, book reviews
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