Rigol oscilloscope prices have sky-rocketed!
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From: Jamie on 6 Jan 2010 20:12 Fred Abse wrote: > On Sun, 03 Jan 2010 09:52:23 -0500, Jamie wrote: > > >>I guess i'll never understand big >>business. > > > Don't let it worry you, most of the people running big business don't > understand it either ;-) > Well, today one of the EE's in the shop left work unexpectedly , shortly after, the IT guy said he needed to get into his office because he was told to extract his HD "C:" drive. Our EE friend didn't return from where ever it was, he went today. Maybe he didn't understand big business either? :) We're not exactly sure what happen at this point, but I told the rest of my colleagues, this is a good time to start a rumor! We'll find out tomorrow, I am sure. :)
From: miso on 7 Jan 2010 22:09 On Jan 6, 2:57 am, Tom <t...(a)no.spam.invalid> wrote: > geoff wrote: > > Sounds more like parallel importing and selling at a lower price than the > > local dealer, rather than 'dumping'. That's not illegal in USAor NZ. Dunno > > about Oz. > > It's probably legal in Australia. I know of of at least one pro photo dealer who sells Canon and Nikon SLRs and equipment from two sources. They source their stuff through legal distributors as well as the do import themselves, many items have two prices and they do explain pitfalls of buying a cheaper one. It's nice to have a choice when you understand what you are getting into. > > Tom We have that in the US, and for the same products. Here we call it gray market. You don't get a US warranty, but you do get to return defective merchandise, so at least you don't get stuck with a dud. I'm using a gray market lens from Canon that has to be 12 years old. No issues. But you only go gray market if the price difference is significant. I don't think I'd get a camera body gray market. Too many things to go wrong.
From: JosephKK on 8 Jan 2010 02:11 On Tue, 5 Jan 2010 02:35:58 -0800 (PST), kreed <kenreed1999(a)gmail.com> wrote: >On Jan 5, 5:15 pm, "m...(a)sushi.com" <m...(a)sushi.com> wrote: >> On Jan 4, 11:09 pm, "Mr.T" <MrT(a)home> wrote: >> >> > <m...(a)sushi.com> wrote in message >> >> >news:23b6594d-3c71-45d0-885a-bb5cbf16ce1f(a)a32g2000yqm.googlegroups.com.... >> >> > >Topaz transformers show up from time to time at electronics flea >> > >markets. In the days when small company owned a Vax, the Topaz was >> > >your isolation transformer. >> >> > Yep, had a Topaz myself once, but I've never seen one going cheap in >> > Australia! Not to say it can't happen, but you'd have to be very lucky, not >> > something the OP can necessarily go and buy at a reasonable price just >> > because he wants it. And not something you'd want to carry in your car >> > either, to use with an inverter supply! >> >> > MrT. >> >> Freight for a Topaz down under would be significant. Topaz has made >> some units that are small, well small for a Topaz. Maybe 12x8x8 >> inches. > > >Ouch ! That is one hell of a transformer :) Naw, at operating frequency of 50/60 Hz that is only about 2000 VA.
From: JosephKK on 8 Jan 2010 02:26 On Tue, 5 Jan 2010 02:34:21 -0800 (PST), kreed <kenreed1999(a)gmail.com> wrote: >On Jan 5, 6:42 pm, "E" <inva...(a)invalid.invalid> wrote: >> "VWWall" <vw...(a)large.invalid> kirjoitti >> viestiss :wN6dnWD6k6DfPt_WnZ2dnUVZ_tedn...(a)earthlink.com... >> >> >> >> > Mr.T wrote: >> >> <m...(a)sushi.com> wrote in message >> >>news:8e1c962a-a471-448b-89b6-7239675017f0(a)k17g2000yqh.googlegroups.com.... >> >>> Surplus isolation transformers are pretty cheap. >> >> >> Yeah when we had surplus stores here I got many big transformers that >> >> way. >> >> They all (electronics surplus stores) disappeared years ago >> >> unfortunately. >> >> > You can make an isolation transformer that will handle a kilowatt from two >> > junked microwave oven transformers. Just remove the HV windings and the >> > magnetic shunt, leaving the primary windings. Connect them together with >> > two coils wound on each core with a few turns of No 12 insulated building >> > wire. Calculate the number of turns to not exceed 20A at the intended >> > maximum load. >> >> Would it work if I just connect HV windings together? >> So as to avoid any rewounding job. >> -ek > > >If you have to do it - try using a pair of 240 - 110v / 48v / 24v >units back to back or other matching voltage low voltage surplus >transformers. > >I did this 25 odd years back using 2 surplus (free) 240v to 24v @15a >units back to back, and it worked fine for many years. It wont be as >efficient as a single purpose designed transformer, and will be >heavier and run hotter. > >Remembering that there will be 2 lots of losses, and that normal >transformers aren't designed to be used "backwards", you will NOT get >the full rated VA out of this arrangement, it will cost more in >electricity use. > > > >I wouldn't even contemplate that idea of putting microwave HT windings >back to back - it would be an absolutely totally and instantly LETHAL >device if anything went wrong, not just an irritating "ZAP". >Please, Please Please do NOT muck about with these things. these >voltages (remember that unlike TV EHT supplies these oven transformers >have plenty of current behind them) can even punch through damaged or >underrated insulated tool handles and to your hand, delivering a >lethal shock ! > > >If there was a breakdown to the output winding, which could possibly >happen with old parts - specially ones from faulty microwaves pulled >from rubbish dumps, or that had mouse / insect infestations - I would >hate to think what could possibly happen to anyone or anything >connected on the 240v isolated "secondary" side. > >If you didnt join the 2 HT windings together in a proper way, and >insulate properly the connection point could even arc, starting a >fire. > > > >Either physically remove the HT winding first if you are going to muck >around with it, or better still, just do yourself a favour and chuck >the microwave oven transformer (and the modification idea) in the >rubbish bin before someone gets killed. > > Not that i recommend that inexperienced persons try such, i do not. Just the same, while i recognize the potential problems, i have no unreasoning fear of them. Nor am i such a nanny type as to insist on trying to prevent anyone from doing something odd but useful. Thus i find you to be quite an obnoxious prunt.
From: JosephKK on 8 Jan 2010 02:48
On Sun, 03 Jan 2010 14:42:09 -0800, Joerg <invalid(a)invalid.invalid> wrote: >Jon Kirwan wrote: >> On Sun, 03 Jan 2010 14:11:39 -0800, Joerg wrote: >> >>> <snip> >>> That's the one I was thinking about. I wouldn't pay a huge fee for any >>> credit card. >> >> I pay zero dollars for my American Express card(s). No >> _direct_ fees, at least, annual or otherwise. I'm sure >> businesses I buy from make certain they make a profit, >> though. So I'm probably paying for it when I buy anything at >> all from a sales outlet that so much as accepts the card. I'm >> probably paying for other cards, too, whether or not I care >> to use them. It all comes out in the wash. (Speaking of >> which, what is the German equivalent for that last idiom?) >> > >Mostly they use a slang expression: "Es ist Pott wie Deckel". Pretty >much not-translateable :-) The closest translation i can propose is "cover the whole pot". |