Cruise ship stuck in ice
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From: Joerg on 6 Mar 2010 10:19 Royston Vasey wrote: [...] > Come on Richard, no need to confuse and agitate the deniers with facts! > :) > Yeah, like the "fact" that the Himalaya range will be ice-free in about 25 years :-) -- SCNR, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Richard Henry on 6 Mar 2010 11:45 On Mar 6, 7:19 am, Joerg <inva...(a)invalid.invalid> wrote: > Royston Vasey wrote: > > [...] > > > Come on Richard, no need to confuse and agitate the deniers with facts! > > :) > > Yeah, like the "fact" that the Himalaya range will be ice-free in about > 25 years :-) > The Baltic situation being discussed is measured, not predicted.
From: Paul Keinanen on 6 Mar 2010 14:09 On Sat, 6 Mar 2010 14:34:00 +0200 (EET), Okkim Atnarivik <Okkim.Atnarivik(a)twentyfour.fi.invalid> wrote: >Paul Keinanen <keinanen(a)sci.fi> wrote: >: Apparently due to the warmingist propaganda, the railroad network in >: Finland is stuck, when there are cold temperatures or some snow and >: trains are hours late, while in the Saint Petersburg region in Russia >: (just 200-400 km East from here) such climate conditions do not cause >: problem for the traffic. > > I agree that probably expectations of warmer and warmer winters has >kept the VR railroad company from investing in snow-tolerant equipment. >Now they are taken by surprise by this downswing in temperature. Still, >I think the cold winter here is just an anecdote - not saying much >about the global average temperature, and even less about what the >long-term trend actually is. The artficially warm recent winters (in >particular 07-08) have felt really creepy. > > Regards, > Mikko In order to keep this discussion on topic, why is it so hard to get component specifications from semiconductor manufacturers for temperatures below 0 C ? I mostly work for a company that ships products all over the world (including Siberia) and we have to test the equipment shipped at low temperatures in order to avoid using military priced components for ordinary industrial applications. In practice, most problems at low temperature systems are associated with getting oscillators to oscillate at low temperatures.
From: Joerg on 6 Mar 2010 14:44 Paul Keinanen wrote: > On Sat, 6 Mar 2010 14:34:00 +0200 (EET), Okkim Atnarivik > <Okkim.Atnarivik(a)twentyfour.fi.invalid> wrote: > >> Paul Keinanen <keinanen(a)sci.fi> wrote: > >> : Apparently due to the warmingist propaganda, the railroad network in >> : Finland is stuck, when there are cold temperatures or some snow and >> : trains are hours late, while in the Saint Petersburg region in Russia >> : (just 200-400 km East from here) such climate conditions do not cause >> : problem for the traffic. >> >> I agree that probably expectations of warmer and warmer winters has >> kept the VR railroad company from investing in snow-tolerant equipment. >> Now they are taken by surprise by this downswing in temperature. Still, >> I think the cold winter here is just an anecdote - not saying much >> about the global average temperature, and even less about what the >> long-term trend actually is. The artficially warm recent winters (in >> particular 07-08) have felt really creepy. >> >> Regards, >> Mikko > > In order to keep this discussion on topic, why is it so hard to get > component specifications from semiconductor manufacturers for > temperatures below 0 C ? > The good ones do. Example from one of my recent hi-rel designs, down to -55C: http://cds.linear.com/docs/Datasheet/6700123ff.pdf Sometimes you have to ask for such data. If a mfg balks at such requests that would be a red flag. > I mostly work for a company that ships products all over the world > (including Siberia) and we have to test the equipment shipped at low > temperatures in order to avoid using military priced components for > ordinary industrial applications. > The ones above weren't very expensive, IIRC around two bucks. > In practice, most problems at low temperature systems are associated > with getting oscillators to oscillate at low temperatures. > Look for categories such as "space and harsh environments", like here: http://www.linear.com/pc/viewCategory.jsp?navId=H0,C1,C1778,C1503 They also have resistor-set oscillators if you can use those: http://cds.linear.com/docs/Information%20Card/LTCMP.pdf What kind of problems do you have to get oscillators started? Russian truckers sometimes light a little wood fire under the engine to warm it a bit but I guess that's not an option in your case :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Okkim Atnarivik on 6 Mar 2010 16:00
Paul Keinanen <keinanen(a)sci.fi> wrote: : In order to keep this discussion on topic, why is it so hard to get : component specifications from semiconductor manufacturers for : temperatures below 0 C ? Actually, more and more modern CMOS semiconductors seem to work even at 4.2K . More so than, say, 15 years ago. My wild guess is that linewidth reduction combined with higher switching speed requirements have driven the manufacturers to use heavier doping levels, attempting to get higher mobility. A side effect is that the carriers no longer freeze out. Regards, Mikko |