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From: Falk Willberg on 21 Jun 2010 02:21 Am 21.06.2010 04:19, schrieb David Nebenzahl: > On 6/20/2010 7:09 PM sparky spake thus: .... >> The jumping over loop is much easier to read on a messed up copy than >> trying to determine if it is a dot or just a smudge. >> Using 5K6 for markings also makes it earier to read. > > Well, then let me ask you the same question I'm asking others here: if > that's so, then why don't we use that system (8K2, etc.) for other > values like voltages, currents, etc? Aren't they also likely to be hard > to read on a "messed-up copy"? Why not be consistent? The range of commonly used resistors starts at about 0R1 and ends at 1M. Capacitors from a few 12pF to some 1000uF. Voltages and currents in common devices do hardly exceed 2V to 400V (uC incl. SPS on mains) resp. 1mA to some 1A. When you find fuse marked 630A in a cell-phone, you do directly know, that it is 630mA. Falk
From: Arfa Daily on 21 Jun 2010 05:04 "David Nebenzahl" <nobody(a)but.us.chickens> wrote in message news:4c1ec026$0$2376$822641b3(a)news.adtechcomputers.com... > On 6/20/2010 5:33 PM Arfa Daily spake thus: > >> "Cydrome Leader" <presence(a)MUNGEpanix.com> wrote in message >> news:hvlhh5$8rh$2(a)reader1.panix.com... > > >>> Arfa Daily <arfa.daily(a)ntlworld.com> wrote: >>>> >>>> "Cydrome Leader" <presence(a)MUNGEpanix.com> wrote in message >>>> news:hvk3bu$3ju$1(a)reader1.panix.com... > >>> >>>>> David Nebenzahl <nobody(a)but.us.chickens> wrote: > >>>> >>>>>> Regarding resistor values: Who the hell came up with that new >>>>>> way of specifying resistance values, like "10R" "or 5K6" or >>>>>> whatever? And why use this system? I've always used the plain >>>>>> value of the resistance: 10, 56, 5.6K, 56K, etc. Simple, >>>>>> obvious, requires no interpretation. Is this some kind of >>>>>> Euro thing? >>>>> >>>>> I first saw that on this newsgroup. My question is what idiots came up >>>>> with it and why? >>>> >>>> Can you really not understand it ? Or are you being deliberately >>>> obtuse ? It has now been explained to the point where a child >>>> could understand it. I think it was actually me who you first saw >>>> using it here, and I'm pretty sure that we went through it all >>>> for your benefit at the time ... >>> >>> That's funny as writing out values the correct and conventional way >>> doesn't need explanation and a child can follow it, and it's been that >>> way >>> for decades. >>> >>> I'm still waiting to see values for money being written out as 44"euro >>> symbol"66 with cents after the end instead of 44.66. >>> >>> periods are too confusing, commas are too confusing! help, we're all >>> stupid these days! >> >> OK then. You started going on about writing voltages in that notation, as >> though you couldn't understand that either. Do they not sell zener diodes >> in America ? That notation has been used for as long as they've been >> around. Like BZY88 C6V8. Have you never seen that, or perhaps you've >> never understood what it meant ? > > Actually, I think you misunderstood *him*. He was saying that if you're > going to use that strange system for resistances, why not also use it for > voltages (or perhaps any quantity) as well? Instead of 5.6 volts, since > you're so all-fired worried about the potential loss of a period (sorry, > full stop), then you should write it as 5V6, no? Or something like that. > > I agree with him. Why the concern about potential loss of decimal-place > information regarding resistances, but not for other parameters like > voltage? > > I think this whole system is needless, and therefore needlessly obtuse, no > matter that people like you may become accustomed to it. How often does a > decimal point actually disappear? Seems as if schematics were drawn the > old "bad" way for decades, and I don't remember any big hullabaloo about > mistaken resistance values. > > But surely, it is you who misses the point. Considering that 30 or 40 years ago, just about all semiconductor houses were American, then is it not likely that it was an American company that came up with the system of marking zener diodes? And why would you imagine it was done ? Why to avoid any ambiguity caused by poorly printed decimal points, of course ... I suppose you're also one of those Luddites who likes to see all of the capacitor values in decimals of a microfarad as well, or have you caught up to nF ? I'm all for not changing systems that are tried and tested just for the sake of it, but I'm just as happy to embrace change where it has a positive benefit. And there is one here. All I can say is that if you have never seen a poorly reproduced schematic where the component identifiers and values are hard to read, then either you are not professionally involved in service work, or you are lying to keep pressing your point. Arfa
From: Arfa Daily on 21 Jun 2010 05:59 "David Nebenzahl" <nobody(a)but.us.chickens> wrote in message news:4c1ec140$0$2377$822641b3(a)news.adtechcomputers.com... > On 6/20/2010 3:25 PM PlainBill47(a)yahoo.com spake thus: > >> As an aside, what is it with people who seem to feel they have a >> god-given right to dictate the 'right' way to do things? If they had >> their way, we'd still be walking everywhere, and seeking shelter in >> trees at night. Things change; usually for the better, sometimes not. >> Deal with it. > > I'll say "point taken", even though you are obviously disagreeing with my > (and others') objection to the 8K2 system of ohmic representations. > > One could just as easily turn that statement of yours around to wonder how > the committee that mandated this new system of nomenclature has a right to > impose their will on us, as the "god-given right to dictate the 'right' > way to do things". > > I just think it's needless, therefore not an improvement, as opposed to > how living in houses is obviously an improvement over seeking shelter in > trees at night. > > (or is it? ... ) > > It's not 'mandated'. Nobody has forced their will on anybody. It's nothing to do with committees, European based or otherwise. I know we have some pretty dumb laws and such forced on us by the Euromachine, but it hasn't reached the point yet where they are dictating how we draw schematics. It's just a system that someone somewhere - probably a Japanese or Korean manufacturer, has come up with because they feel that it removes any possibility of ambiguity on a component value. It's a bit like putting traffic light turn filter arrows on junctions. For sure, you could argue that it's not strictly necessary in order to be able to successfully negotiate the junction. You can do that on a green light alone. But putting a filter arrow there, removes any ambiguity from when it's safe to go, particularly for less experienced drivers, or those not absolutely familiar with a junction. And as to voltages, some schematics do now use the system for showing voltages that are in decimal parts. "3V3" is commonly found on schematics. It's also common now to find the same system in use for capacitors, so 4n7 for instance or 2u2. Whether you like the system or not, it seems to be getting used more and more, so I think it's a case of learn it and accept it. It's really no more difficult than any system currently in use, just different, and it *can* under some circumstances, be an improvement. Arfa
From: Cydrome Leader on 21 Jun 2010 14:05 Arfa Daily <arfa.daily(a)ntlworld.com> wrote: > > > "David Nebenzahl" <nobody(a)but.us.chickens> wrote in message > news:4c1ec026$0$2376$822641b3(a)news.adtechcomputers.com... >> On 6/20/2010 5:33 PM Arfa Daily spake thus: >> >>> "Cydrome Leader" <presence(a)MUNGEpanix.com> wrote in message >>> news:hvlhh5$8rh$2(a)reader1.panix.com... >> > >>>> Arfa Daily <arfa.daily(a)ntlworld.com> wrote: >>>>> >>>>> "Cydrome Leader" <presence(a)MUNGEpanix.com> wrote in message >>>>> news:hvk3bu$3ju$1(a)reader1.panix.com... >> >>> >>>>>> David Nebenzahl <nobody(a)but.us.chickens> wrote: >> >>>> >>>>>>> Regarding resistor values: Who the hell came up with that new >>>>>>> way of specifying resistance values, like "10R" "or 5K6" or >>>>>>> whatever? And why use this system? I've always used the plain >>>>>>> value of the resistance: 10, 56, 5.6K, 56K, etc. Simple, >>>>>>> obvious, requires no interpretation. Is this some kind of >>>>>>> Euro thing? >>>>>> >>>>>> I first saw that on this newsgroup. My question is what idiots came up >>>>>> with it and why? >>>>> >>>>> Can you really not understand it ? Or are you being deliberately >>>>> obtuse ? It has now been explained to the point where a child >>>>> could understand it. I think it was actually me who you first saw >>>>> using it here, and I'm pretty sure that we went through it all >>>>> for your benefit at the time ... >>>> >>>> That's funny as writing out values the correct and conventional way >>>> doesn't need explanation and a child can follow it, and it's been that >>>> way >>>> for decades. >>>> >>>> I'm still waiting to see values for money being written out as 44"euro >>>> symbol"66 with cents after the end instead of 44.66. >>>> >>>> periods are too confusing, commas are too confusing! help, we're all >>>> stupid these days! >>> >>> OK then. You started going on about writing voltages in that notation, as >>> though you couldn't understand that either. Do they not sell zener diodes >>> in America ? That notation has been used for as long as they've been >>> around. Like BZY88 C6V8. Have you never seen that, or perhaps you've >>> never understood what it meant ? >> >> Actually, I think you misunderstood *him*. He was saying that if you're >> going to use that strange system for resistances, why not also use it for >> voltages (or perhaps any quantity) as well? Instead of 5.6 volts, since >> you're so all-fired worried about the potential loss of a period (sorry, >> full stop), then you should write it as 5V6, no? Or something like that. >> >> I agree with him. Why the concern about potential loss of decimal-place >> information regarding resistances, but not for other parameters like >> voltage? >> >> I think this whole system is needless, and therefore needlessly obtuse, no >> matter that people like you may become accustomed to it. How often does a >> decimal point actually disappear? Seems as if schematics were drawn the >> old "bad" way for decades, and I don't remember any big hullabaloo about >> mistaken resistance values. >> >> > > But surely, it is you who misses the point. Considering that 30 or 40 years no, it's you that doesn't get it. > ago, just about all semiconductor houses were American, then is it not > likely that it was an American company that came up with the system of > marking zener diodes? And why would you imagine it was done ? Why to avoid > any ambiguity caused by poorly printed decimal points, of course ... you mean like a 1N5351? > I suppose you're also one of those Luddites who likes to see all of the > capacitor values in decimals of a microfarad as well, or have you caught up > to nF ? > > I'm all for not changing systems that are tried and tested just for the sake > of it, but I'm just as happy to embrace change where it has a positive > benefit. And there is one here. All I can say is that if you have never seen > a poorly reproduced schematic where the component identifiers and values are > hard to read, then either you are not professionally involved in service > work, or you are lying to keep pressing your point. So when is the last time you got confused over "missing" periods again? seriously.
From: Cydrome Leader on 21 Jun 2010 14:07
David Nebenzahl <nobody(a)but.us.chickens> wrote: > On 6/20/2010 7:09 PM sparky spake thus: > >> On Jun 18, 4:18 pm, David Nebenzahl <nob...(a)but.us.chickens> wrote: > > >>> Someone else made a comment in another thread here about weird >>> schematics (like for home appliances). >>> >>> Wanted to get a small discussion going on that topic. My take: there are >>> good and bad standards for schematics. Personally, I can't stand the >>> ones that use rectangle shapes for resistors, instead of the traditional >>> zigzag that [insert name of deity here] intended to be used. (And even >>> here there are lots of variations, like old-fashioned schematics that >>> took this symbol rather literally and sometimes had ten or twelve zigs >>> and zags, as if an actual resistor was being constructed on paper). >>> >>> Likewise the wire-connecting/jumping convention: here I much prefer the >>> modern approach, which is to use a dot for a connection and no dot for >>> no connection, rather than the clumsy "loop" to indicate one wire >>> jumping over another with no connection. >> >> The jumping over loop is much easier to read on a messed up copy than >> trying to determine if it is a dot or just a smudge. >> Using 5K6 for markings also makes it earier to read. > > Well, then let me ask you the same question I'm asking others here: if > that's so, then why don't we use that system (8K2, etc.) for other > values like voltages, currents, etc? Aren't they also likely to be hard > to read on a "messed-up copy"? Why not be consistent? the short answer is they don't know, and like being slaves to stupid committees. |