BIG heatsink....

I don't see any problem using this method for R's C's and L's and maybe voltage. I do this too and it does have a couple of advantages. One less digit and don't have to look harder for a printed decimal points if the printer wasn't so good.

I kinda think it's going a bit overboard for the other units or quantities and I don't see those except here maybe.

boB

What about transistors? Certainly you've heard of the famous 2.2222 (wonder why the identifier is an 'N'? ;)?

If a fixed pitch font is used, the decimal point is obvious, though the European nomenclature still saves a character (perhaps more important). I use the nomenclature for voltages but passives are controlled by the corporation (they use the decimal point) so no choice.

I still think the national debt should be in dB(USD). After Obama, at least it will look linear.

Especially voltage - BZY88C4V7, unambiguous. Diodes are hard enough to read, without having to look for decimal points. 4.7V or 47V?

Are you kidding? They should hide all those numbers in a datasheet and make the customer guess what the designation is! 1N4733, 1N4742...

Tim

Apparently you don't have to work with less than perfectly clear schematics and datasheets. I do, all the time. Some of them are old enough that the manufacturer never published them in digital form. Scanned copies floating on the internet are often quite horrible in quality but better than nothing. Even if a dp is not completely missing, it's far easier to positively identify its presence with the Euro style.

Other than as a joke, who runs things though a photocopier 10 times or faxes it over and over again?

When is the last time you (or anybody) even photocopied or faxed a schematic? Have you used your microfiche reader/printer lately? I think all the kerosene toner in mine dried up, about 400 years ago.

well, the Danish aren't know for excellence in engineering or banking, so it probably doesn't matter what they use to group digits or indicate decimal places. As for the Germans, well, they still use slotted screws.

Are you sure that if I faxed and photocopied 4R7 dozens of times that the R might not end up looking like a k? Think about this. R and k. They look pretty close to me.

maybe it's a .47 volt diode. Those secret missing periods could be anywhere.

Do you have a time machine to go back and clean up all those old schematics? Is anything drawn by hand today?

Not really. A decimal point takes space, more if written in a fixed font. In any case, there should always be a leading zero for values less than one.

decimal

I have seen a lot of proprietary protocol specifications floating from one organization to the other, photocopied at each organization.

Sure. About 75% of my electronics work product for clients is hand-drawn schematics, done freehand with a drafting pencil on B-size vellum, plus BOMs as flat text files. Clients mostly have their folks do the schematic capture and layout under my supervision, because (a) it's much cheaper, and (b) it gets the design into their CAD system with their documentation requirements met.

I use the 4k7 style uniformly--the first time I saw it, probably 30 years ago, I said, "That's a good idea" and switched.

Of course, my stuff is mostly front ends, laser controllers, PLLs, analogue signal processing, data acq, and so forth--stuff that has to be quiet and stable but doesn't have 768-pad BGAs and so on, so usually it only takes two or three B-size sheets.

Cheers

Phil Hobbs

decimal

Odd. Everywhere I've worked this stuff is formally documented and kept on a secure drive. If it's really considered the "family jewels" (very rarely should be) its distribution is controlled as is any other such document. If it's *really* high-level stuff, it's printed on red "DO NOT COPY" watermark paper (if you see a black version of the watermark, arrest the holder ;-). This stuff was really rare, though.

decimal

I always insist on an original electronic copy. In my business that has to exist, at least in netlist form, otherwise how can you do LVS verification? ...Jim Thompson

I haven't submitted a hand-drawn schematic to a customer in probably

(*) On that Long Island project the "junior engineer" was 2-years older than me ;-) ...Jim Thompson

YOur deliverables are hand drawn? Are all you contracts on the back of a napkin, too? ;-)

I use it for voltages but not passives. Never had the choice.

You can fit a lot on a couple of B-sized sheets. My current boards' schematics are on 7 and 11, B-sized sheets and there's around 1500 components on each board.

I don't draw more than scribbles by hand, and that generally on nothing larger than a post-it.

Dunno about that, -015V seems a bit cumbersome..

;-)

Merry Christmas to all..

Best regards, Spehro Pefhany

decimal

In many countries (such as within the EU) it is completely legal to us reverse engineering/disassembly to find the interface with foreign product to find the interface to these products.

Of course, this does not give you the right to make a verbatim copy of this product.

decimal

OK but I don't see the relevance to hand-drawn or copied documentation.

read,

Why would you write 15V that way? ...or did you perhaps mean 0.15V (which I would write in a signal name as 0V15)? ;-)

What he said!