Posts by Bill Walker

1) Message boards : Cafe SETI : The Train Thread 2 (Message 1809782)
Posted 17 Aug 2016 by Profile Bill Walker
A few hundred miles north of Bernie's pictures, it has been a wetter than usual summer in Alberta, and the flowers have lasted longer than usual. Photo taken on 6 August.

2) Message boards : Cafe SETI : The Train Thread 2 (Message 1809768)
Posted 17 Aug 2016 by Profile Bill Walker
Bill - to someone born and brought up in the UK anywhere more than 100km (60 miles) is "in the wilds".....

Well, depends on where you are in Canada. Here in SW Ontario 100 km will take you through several little towns, and maybe one medium sized one. On the prairies 100 km is one or two farms over. In the Territories 100 km is a small bit of the trip to anywhere.
3) Message boards : Cafe SETI : Photographs by Setizens - Originals only - any subject (Message 1809208)
Posted 15 Aug 2016 by Profile Bill Walker
Here is another one to ponder on a hot day. Business trip, 2014.
4) Message boards : Cafe SETI : The Train Thread 2 (Message 1808958)
Posted 13 Aug 2016 by Profile Bill Walker
...thanks for that bit of information Bill - in just over a month's time I will be heading out into the wilds of Canada by train....

From my point of view, if you can get there by train, it's not the wilds. Getting to the wilds involves several days by canoe and/or snowmobile. Although some railroads herabouts let you combine modes of travel.

5) Message boards : Cafe SETI : The Train Thread 2 (Message 1808868)
Posted 13 Aug 2016 by Profile Bill Walker
Looks like bad planning on the part of the RR. We have some similar stations here in eastern Canada, but VIA has electronic notice boards that tell you in advance what track your train will be on, in very simple terms ("11:45 to Toronto on the other side"). Busier stations, like here in London, have the notices plus a well lit tunnel under the tracks.
6) Message boards : Cafe SETI : The Train Thread 2 (Message 1808809)
Posted 13 Aug 2016 by Profile Bill Walker
Bernie, Ashland looks like a perfect model railway project. Thanks for the shots.
7) Message boards : Cafe SETI : Transportation Safety 3 (Message 1808053)
Posted 9 Aug 2016 by Profile Bill Walker
A Boeing 737 cargo from Paris to Orio al Serio (Bergamo) overshot the runaway and ended with its nose on a highway during a storm. Fortunately it was 4 AM and the motorists were few so they could avoid it.

Reminds me of a radio transmission years ago from a California airport, tower talking to a plane that just landed a bit far down the runway:

"Nxxx left at last exit if possible. If not possible, continue north on I5, take the Elm Street exit, right at the Gulf station back to airport."
8) Message boards : Cafe SETI : Photographs by Setizens - Originals only - any subject (Message 1808052)
Posted 9 Aug 2016 by Profile Bill Walker
Agwa Canyon, fall of 2014. I posted the train pictures before, but there was other stuff to see too.

9) Message boards : Cafe SETI : The Train Thread 2 (Message 1806631)
Posted 2 Aug 2016 by Profile Bill Walker
The train museum in York is the best I've seen so far. There is a very good museum in Montreal, with Canadian built locos, and the train museum near Edmonton, Alberta is a sentimental favourite. They operate a couple of steam engines in the summer, fond memories of riding them with the kids when they were very young.
10) Message boards : Cafe SETI : Name your top 3+ music artists (Message 1806146)
Posted 31 Jul 2016 by Profile Bill Walker
Changes every day. Right now, it is the 3 Bs of classical music:

11) Message boards : Cafe SETI : Don't know where it should go? Stick it here! Part III (Message 1804250)
Posted 22 Jul 2016 by Profile Bill Walker
You guys did notice the radio show this is from? The same show that brought stories like "Saskatchewan government to teach teens how to kiss" and "World's first volunteer run, non-profit McDonalds opens in Manitoba". Don't take them too seriously.

WARNING: Canadian humour may be misleading to others.
12) Message boards : Cafe SETI : State Fairs (Message 1803039)
Posted 16 Jul 2016 by Profile Bill Walker
We have town fairs and country fairs here, in a range of sizes. The big ones (like the CNE in Toronto) are probably like your state fairs. My wife and I love the smaller rural fairs. Prizes for best pies and pickles, best handicrafts (my mother-in-law won several knitting awards at her local fair), livestock displays, usually a local car club or antique tractor club display, and lots of good food. Everything from the local ladies auxiliary doing fried chicken and home made corn dogs (not the mass produced crap some places have), to big travelling food trucks with slick new things every year. Deep fried butter, doughnut burgers, etc. They will have a midway with rides and games, but we give those a miss nowadays.
13) Message boards : Cafe SETI : Raccoon Update XXIII - All Are Welcome In The Critter Cafe (Message 1801224)
Posted 7 Jul 2016 by Profile Bill Walker
Finally! fire flies in the back yard the last few nights. A few weeks late, but here they are.
14) Message boards : Cafe SETI : The Train Thread 2 (Message 1800640)
Posted 4 Jul 2016 by Profile Bill Walker
Now that would be a cool commute.
15) Message boards : Cafe SETI : 78's (Message 1800534)
Posted 4 Jul 2016 by Profile Bill Walker
I find it interesting that everybody digs up info about deterioration of digital data when we discuss backups, but they never offer an alternative. I've recently gained access to original paper records dating back to the 1920s in government archives, and some of them are in rough shape. Paper deteriorating and crumbling, ink and pencil fading, etc. Even stuff as recent as the 1950s can be borderline useless. My Kodachrome slides from the 1960s and 1970s are fading.

Nothing is perfect. Any form of record keeping requires regular production of new backups.
16) Message boards : Cafe SETI : The Train Thread 2 (Message 1800246)
Posted 3 Jul 2016 by Profile Bill Walker
Just a reminder that not all engines are grey in North America. My daughter used to live about 5 blocks from the Denver yard, a great place for train spotting.

17) Message boards : Cafe SETI : 78's (Message 1799942)
Posted 1 Jul 2016 by Profile Bill Walker
Thank you, Bill, for a very thorough explanation. It honestly makes me value my records even more. I have a converter machine from Hammacher Schlemmer that will transfer them to CD, but from what I'm gathering here, that result will not be as durable as an original commercially produced disc.

If the conversions go onto writeable disc, you have about a decade - if you are careful. I have a few of those, burned off records, and I am transferring them all to hard disc. With my regular backup scheme, I'm hoping they will last as long as I do.

I still have just over 300 LPs, with a few new ones bought each month (only because second hand LPs are cheaper than new CDs). I love the sound, but they are prone to mechanical wear. Even on the best record players, you can hear a slight degradation after a few playings. I know a lot of people hate CDs, but they just have different shortcomings compared to LPs, and a lot of us are just used to the LP shortcomings. I'm getting into higher resolution digital formats (24 bit 96 kHz for now) and I think that is the best compromise between playback quality and longevity (again with regular backups).
18) Message boards : Cafe SETI : 78's (Message 1799687)
Posted 30 Jun 2016 by Profile Bill Walker

So a commercial CD actually has a braille-like series of binary code imprinted on it?

Not bumps like Braille, but pits. The untouched level area is called a land, pits and lands reflect the laser differently so one is a zero and the other is a one. (Forget which is which). The pits are in a spiral, which can be several miles long if it was unwound. The pits are microscopic.

You start with a thin layer of plastic that gets the pits pressed into the front of them from a metal master. The back is coated with a reflective metal, usually aluminium, then a layer of lacquer (transparent paint) and then the label can be printed on top of that. The other side, with the pits, gets a relatively thick layer of transparent lexan molded onto it. You can scratch and mark this, to some degree, but the pits and lands are untouched unless you get all the way through the lexan. Hence the durability of this type of CD. You just have to make sure the all the layers bond well to each other.

On a standard CD it takes 16 bits to make a single burst of music that is 1/44,000 of a second long. (thats 0.000022727 seconds.) Most modern CD players have some sort of error checking, so if a single pit or land gets read wrong the 16 bit number will fail parity check, and get replaced with the average of the number before and the number after. (More expensive players can have fancier error correction that can handle multiple read errors.) A single substitution like this is not audible. If you scratch or mark the lexan in a curve parallel to the edge of the disc you can screw up multiple numbers one after another, and then the error correction can sound weird, or even lead to skipping or periods of silence.

Fortunately, if you have scratches the lexan is polish-able with something like Brasso. You don't have to polish out the entire scratch, just round off the edges. The sharp corners screw up the laser light and lead to reading errors. Just make sure you get all the fine dust off the disc before you put in your player. I do this quite regularly with second hand CDs and even loaners from the public library. Dish soap in warm water works well for finger prints and other substances on the lexan. As long as the pits and lands are untouched, you can get back all the music.
19) Message boards : Cafe SETI : Raccoon Update XXIII - All Are Welcome In The Critter Cafe (Message 1799682)
Posted 30 Jun 2016 by Profile Bill Walker
The wife and I were just commenting that we haven't seen any lightning bugs so far this year, which is not normal. Hopefully this is just natural cycles, and they will return in the future. Chipmunks, on the other hand, have overrun the place this year.
20) Message boards : Cafe SETI : 78's (Message 1799037)
Posted 27 Jun 2016 by Profile Bill Walker
A lot depends on how the CD was made and how it is treated. Volume production usually molds the 0s and 1s into a plastic base and then covers that in lexan. If you keep that away from heat and solvents, and don't scratch the lexan too much, it should last a few centuries. If you use dye based writable Cds, which some smaller publishers do, don't expect it to last much more than a decade. Much less, if the dye is exposed to UV, like sunight.

The examples above sound like poor quality control in applying the lexan layer.

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