A good digital oscilloscope?
in [Design]
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From: Michael A. Terrell on 12 Dec 2009 22:04 Joerg wrote: > > krw wrote: > > On Fri, 11 Dec 2009 11:32:44 -0800, Joerg <invalid(a)invalid.invalid> > > wrote: > > > >> Joel Koltner wrote: > >>> "Joerg" <invalid(a)invalid.invalid> wrote in message > >>> news:7ob08jF3oortqU1(a)mid.individual.net... > >>>> But wait, $600 for a Christmas gift? Ain't that a bit over the top? > >>> Only a little... I think that $250-$500 per kid for Xmas today is not at > >>> all uncommon today... > >>> > >>>> As a kid I had to work for stuff like that. For example at a meat > >>>> factory until I had the $400 for my first used and pretty banged up > >>>> HW100 transceiver. > >>> I doubt you can legally work at a meat factory unless you're at least 18 > >>> today. :-( > >>> > >>> If you want to see some kids with wealthy parents who are *seriously* > >>> spoiled, check this out: > >>> http://www.mtv.com/shows/sweet_16/episodes.jhtml . It's not uncommon on > >>> that show for the parents to blow $25-$100k on their kid's 16th birthday! > >>> > >>> If I had the choice between a Lexus and, I dunno, a Civic and a bunch of > >>> test equipment, I think it'd be obvious which I'd choose... > >>> > >> What I really don't understand is when a couple goes into big time debt > >> just for the wedding ceremony, and often the bride's folks as well. I've > >> heard of one couple who "had to" sell their home and move into an > >> apartment to give their daughter an "appropriate" wedding. > >> > >> We made sure that neither of our parents had to pay anything and that > >> our wedding ceremony was reasonable and could be comfortably paid from > >> our savings (without raiding the account). Credit card use for the > >> wedding was zilch. > > > > I was in college when we got married. Her parents paid for everything > > but the minister (that cost me a week's pay and he only charge me half > > the normal $100 ;). I think they shelled out about $1000 but 80% of > > that was the dress. It still haunts me (moved it twice in the last > > two years). > > The amazing thing is that my wife still fits into her dress. I, on the > other hand ... Shouldn't be wearing a dress? :) -- Offworld checks no longer accepted!
From: JosephKK on 13 Dec 2009 10:02 On Mon, 07 Dec 2009 20:21:56 -0800, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >This is a 4FP7 airborne radar display tube, ca WWII. It has a fast >blue phosphor that excites a slow yellow one. Blasted with electrons >(or a flashlight) it will glow for several minutes. > >ftp://jjlarkin.lmi.net/4FP7.jpg > >John P7 phosphors were very common on all sorts of air search radar (PPI - plan position indicator) displays post WW2. I have seen them on SPS-48 and SPS-51 native radar displays.
From: JosephKK on 13 Dec 2009 11:04 On Thu, 10 Dec 2009 10:11:28 -0800, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On 10 Dec 2009 17:26:14 GMT, Robert Latest <boblatest(a)yahoo.com> >wrote: > >>Joerg wrote: >> >>> Back in those days watch dials would be readable all night, not nearly >>> have that much decay. That is no longer the case, no matter what fancy >>> material they use. >> >>I wonder if the phosphorescence of that radium compound has anything to >>do with the radium's radioactivity. Maybe the radioactivity helps to get >>the energy into or back out of the long-term storage states. >> >>robert > >Of course it does. Radium phosphors will glow in the dark for >centuries. That's what the radium is for. Tritium too, except its >half-life is around 12 years. > >John > Roger on the beta decay driving the luminescence. But not on the centuries life, the half life of Radium 228 is only 5.7 years.
From: JosephKK on 13 Dec 2009 11:35 On Mon, 07 Dec 2009 13:19:02 -0800, Joerg <invalid(a)invalid.invalid> wrote: >Jan Panteltje wrote: >> On a sunny day (Sun, 6 Dec 2009 22:18:04 -0600) it happened "Tim Williams" >> <tmoranwms(a)charter.net> wrote in <hfhvm1$bp$1(a)news.eternal-september.org>: >> >>> *Just because it's an analog scope doesn't mean you don't get storage or >>> single sweep type readings, it just means it takes more setup. This >>> photograph was taken with a 10 second exposure, capturing three photoflash >>> discharges: >>> http://webpages.charter.net/dawill/Images/Photoflash_Discharge2_sm.jpg >>> >>> Tim >> >> That is only a simple example, analog scopes can do far more then that: >> http://panteltje.com/panteltje/scope_tv/index.html >> And that one is 30 years old, and only 10MHz, > > >Nice. Problem is there aren't that many scopes with a Z-input anymore. >That Trio scope must be older than 30. Probably like my Hameg 8MHz scope >that is now around 35. No trigger, just a "synchronizer". > >Judging by the DVD you are watching there I assume you must have >grandkids :-) The last time i saw a synchronizer type 'scope was over 40 years ago, it was a neighbors prize possession and 10+ years old even then.
From: Tim Williams on 13 Dec 2009 11:45
"JosephKK" <quiettechblue(a)yahoo.com> wrote in message news:vr5ai5tjh0b59t76e4362bufh7ufgp0n97(a)4ax.com... > The last time i saw a synchronizer type 'scope was over 40 years ago, it > was a neighbors prize possession and 10+ years old even then. http://webpages.charter.net/dawill/tmoranwms/Elec_Scope1_lg.jpg Well, it says "TRIG LEVEL" on the outer knob, but it has this peculiar "STABILITY" on the inner knob. I never did completely understand the circuit in this thing (I have the kit instructions, so I have all the drawings), it's drawn so as to make a minimum of sense. Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms |