X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/b3c964df1699fb995f5bccafd7cfda232e514dbb..e0249d1b5ff7c1a80a224b3a347d3d25b990cc65:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index 00c8766465..7b873ab2a3 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -6,6 +6,52 @@ http://people.skolelinux.org/pere/blog/ + + Hvordan kringkaster T-banen i Oslo sine overvåkningskamerasignaler? + http://people.skolelinux.org/pere/blog/Hvordan_kringkaster_T_banen_i_Oslo_sine_overv__kningskamerasignaler_.html + http://people.skolelinux.org/pere/blog/Hvordan_kringkaster_T_banen_i_Oslo_sine_overv__kningskamerasignaler_.html + Wed, 5 Jan 2011 18:30:00 +0100 + +<p>Jeg er den fornøyde eier av en håndholdt trådløs kamerascanner, +dvs. en radioscanner som automatisk scanner frekvensområdet 900 - 2500 +MHz og snapper opp radiokilder med PAL eller NTCS TV-signal og viser +signalet frem på en liten skjerm. Veldig morsom å ha med seg for å se +hva som finnes av trådløse overvåkningskamera. En får se bildet som +kameraet tar opp. :)</p> + +<p>Men en kilde har den ikke klart å snappe opp: Sporveiens +overvåkningskamera på T-banestasjonene. Bildet sendes åpenbart +trådløst til T-baneføreren, men min scanner har ikke klart å ta inn +signalet. For å forsøke å finne ut av dette tok jeg i dag en nærmere +titt på en av boksene som sto på Forskningsparken T-banestasjon for å +se hva det er som sendes ut.</p> + +<p>Boksen hadde følgende tekst:</p> + +<blockquote><pre> +SupraLink +Outdoor Transmitter 5.8 GHz + +default channel [ ] + identity code [ ] + +VTQ Videotronik +06268 Querfurt +<a href="http://www.vtq.de/">www.vtq.de</a> +Made in Germany + +AC 230V [strekkode] +max 10W 84230936 +</pre></blockquote> + +<p>Det var hyggelig av produsenten å legge inn lenke til nettsiden +sin. Der hadde de mye stilig elektronikk. Og forklaringen på hvorfor +min scanner ikke tar inn signalet er åpenbar ut fra merkelappen. 5.8 +GHz er langt over min scanners grense på 2.5 GHz. Trenger visst en +kraftigere scanner. :)</p> + + + Inspirerende fra en ukjent Skolelinux-skole http://people.skolelinux.org/pere/blog/Inspirerende_fra_en_ukjent_Skolelinux_skole.html @@ -1050,90 +1096,5 @@ RHEL6 with glxgears. No idea why.</p> - - Some thoughts on BitCoins - http://people.skolelinux.org/pere/blog/Some_thoughts_on_BitCoins.html - http://people.skolelinux.org/pere/blog/Some_thoughts_on_BitCoins.html - Sat, 11 Dec 2010 15:10:00 +0100 - -<p>As I continue to explore -<a href="http://www.bitcoin.org/">BitCoin</a>, I've starting to wonder -what properties the system have, and how it will be affected by laws -and regulations here in Norway. Here are some random notes.</p> - -<p>One interesting thing to note is that since the transactions are -verified using a peer to peer network, all details about a transaction -is known to everyone. This means that if a BitCoin address has been -published like I did with mine in my initial post about BitCoin, it is -possible for everyone to see how many BitCoins have been transfered to -that address. There is even a web service to look at the details for -all transactions. There I can see that my address -<a href="http://blockexplorer.com/address/15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a> -have received 16.06 Bitcoin, the -<a href="http://blockexplorer.com/address/1LfdGnGuWkpSJgbQySxxCWhv8MHqvwst3">1LfdGnGuWkpSJgbQySxxCWhv8MHqvwst3</a> -address of Simon Phipps have received 181.97 BitCoin and the address -<a href="http://blockexplorer.com/address/1MCwBbhNGp5hRm5rC1Aims2YFRe2SXPYKt">1MCwBbhNGp5hRm5rC1Aims2YFRe2SXPYKt</A> -of EFF have received 2447.38 BitCoins so far. Thank you to each and -every one of you that donated bitcoins to support my activity. The -fact that anyone can see how much money was transfered to a given -address make it more obvious why the BitCoin community recommend to -generate and hand out a new address for each transaction. I'm told -there is no way to track which addresses belong to a given person or -organisation without the person or organisation revealing it -themselves, as Simon, EFF and I have done.</p> - -<p>In Norway, and in most other countries, there are laws and -regulations limiting how much money one can transfer across the border -without declaring it. There are money laundering, tax and accounting -laws and regulations I would expect to apply to the use of BitCoin. -If the Skolelinux foundation -(<a href="http://linuxiskolen.no/slxdebianlabs/donations.html">SLX -Debian Labs</a>) were to accept donations in BitCoin in addition to -normal bank transfers like EFF is doing, how should this be accounted? -Given that it is impossible to know if money can across the border or -not, should everything or nothing be declared? What exchange rate -should be used when calculating taxes? Would receivers have to pay -income tax if the foundation were to pay Skolelinux contributors in -BitCoin? I have no idea, but it would be interesting to know.</p> - -<p>For a currency to be useful and successful, it must be trusted and -accepted by a lot of users. It must be possible to get easy access to -the currency (as a wage or using currency exchanges), and it must be -easy to spend it. At the moment BitCoin seem fairly easy to get -access to, but there are very few places to spend it. I am not really -a regular user of any of the vendor types currently accepting BitCoin, -so I wonder when my kind of shop would start accepting BitCoins. I -would like to buy electronics, travels and subway tickets, not herbs -and books. :) The currency is young, and this will improve over time -if it become popular, but I suspect regular banks will start to lobby -to get BitCoin declared illegal if it become popular. I'm sure they -will claim it is helping fund terrorism and money laundering (which -probably would be true, as is any currency in existence), but I -believe the problems should be solved elsewhere and not by blaming -currencies.</p> - -<p>The process of creating new BitCoins is called mining, and it is -CPU intensive process that depend on a bit of luck as well (as one is -competing against all the other miners currently spending CPU cycles -to see which one get the next lump of cash). The "winner" get 50 -BitCoin when this happen. Yesterday I came across the obvious way to -join forces to increase ones changes of getting at least some coins, -by coordinating the work on mining BitCoins across several machines -and people, and sharing the result if one is lucky and get the 50 -BitCoins. Check out -<a href="http://www.bluishcoder.co.nz/bitcoin-pool/">BitCoin Pool</a> -if this sounds interesting. I have not had time to try to set up a -machine to participate there yet, but have seen that running on ones -own for a few days have not yield any BitCoins througth mining -yet.</p> - -<p>Update 2010-12-15: Found an <a -href="http://inertia.posterous.com/reply-to-the-underground-economist-why-bitcoi">interesting -criticism</a> of bitcoin. Not quite sure how valid it is, but thought -it was interesting to read. The arguments presented seem to be -equally valid for gold, which was used as a currency for many years.</p> - - -