On Monday, March 12, 2018 at 12:36:33 AM UTC-4, John Larkin wrote:
> On Sun, 11 Mar 2018 20:14:07 -0700, boB <boB@K7IQ.com> wrote:
> 
> >On Mon, 12 Mar 2018 00:30:32 GMT, Steve Wilson <no@spam.com> wrote:
> >
> >>John Larkin <jjlarkin@highlandtechnology.com> wrote:
> >>
> >>> SI format clearly distinguishes between exponents and dimensional
> >>> units. The 4k7 thing is just ugly and sloppy.
> >> 
> >>> Modern decimal points don't fall off drawings. Properly drawn decimal
> >>> points never did.
> >> 
> >>There is a readability problem with decimal values. For example, .47uF on a 
> >>large drawing can be misinterpreted to mean 47uF.
> >>
> >>One solution is to add a zero in front of the decimal so it reads 0.47uF
> >>
> >>I know you already know that. Just mentioning it for others.
> >
> >Some Zener diodes use the form 6V2  in their  part numbers
> >
> >Takes less space also.
> >
> >As for 0.47uF, I always add the leading zero.
> >
> >Also, on schematics, I have learned to not  use 4-way tie points
> >because of the sometimes ambiguity of the wire crossing or connecting
> >whether or not the dot is huge and visible.
> >
> >
> >
> 
> I don't understand all this dot/decimal paranoia. Make them clean and
> visible. Deliberate offsetting of natural 4-way connections makes ugly
> schematics, as does the 4K7 notation.
> 
> 
> 
> 
> 
> 
> -- 
> 
> John Larkin         Highland Technology, Inc
> 
> lunatic fringe electronics

Though I have no problem with the 4K7 notation and I have actually started using it, I only use it on resistors. I don't know of any "standard" for other components. I do sometimes use "104" instead of 0.1uF or 100nF, especially since many caps are labeled that way.

Anyone who writes a number using a leading decimal point (without a zero in front of it) around here is looking for trouble.

Jasen Betts wrote:
> On 2018-03-19, Jeroen Belleman <jeroen@nospam.please> wrote:
>> Jasen Betts wrote:
>>> On 2018-03-18, Jeroen Belleman <jeroen@nospam.please> wrote:
>>>> On 17/03/18 10:10, Robert Baer wrote:
>>>>> Joerg wrote:
>>>>>> Sorry for the occasional non-political post ...
>>>>>>
>>>>>> In the past I have seen special character issues with netlists across
>>>>>> foreign country boundaries. For example, in some countries they use a
>>>>>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>>>>>> some part numbers. That can blow a netlist out of the water.
>>>>>>
>>>>>> How about a real decimal point (a dot) inside a footprint?
>>>>>>
>>>>>> Main reason I ask is for mounting hole designators. A client wants all
>>>>>> this in metric dimensions and that will require fractions of a
>>>>>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>>>>>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>>>>>> such and that's less understandable.
>>>>>>
>>>>>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
>>>>> so .. why not 4MM5_DRILL?
>>>>>
>>>> I would write that as 4m5 m. The 4m5 is the number, the final m is
>>>> the unit. I would also favour writing 1 mm^2 as 1u m^2, because I
>>>> think that the multiplier 'prefixes' should apply to the number
>>>> rather than to the unit, but that's not likely to please anyone.
>>> or you could write 10na ot 10zb and confuse everyone :)
>>>
>> I don't know what a and b are, but it's perfectly clear that
>> we have 1e-8 of one and 1e-20 of the other.
> 
> I said it would confuse everyone. it confused me, I meant Zb 
> 
> ares and barns - two SI-ish  units of area.
> 

Both ares and barns are 'convenience units' used by specialists.
I happen to be working in an environment where the latter is
used all the time, in fact. I'm of the opinion that convenience
units should be stamped out, in favour of pure SI units, always,
everywhere.

That said, the use of multiplier prefixes with area units are a
blemish on the SI system, where suddenly the interpretation
changes from <prefix> to <prefix^2>. I'm not even sure if that
applies to barns, but it does to meters.

Jeroen --Begone barn, are, gal, angstrom, AU, parsec, etc.-- Belleman

On 2018-03-19, Jeroen Belleman <jeroen@nospam.please> wrote:
> Jasen Betts wrote:
>> On 2018-03-18, Jeroen Belleman <jeroen@nospam.please> wrote:
>>> On 17/03/18 10:10, Robert Baer wrote:
>>>> Joerg wrote:
>>>>> Sorry for the occasional non-political post ...
>>>>>
>>>>> In the past I have seen special character issues with netlists across
>>>>> foreign country boundaries. For example, in some countries they use a
>>>>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>>>>> some part numbers. That can blow a netlist out of the water.
>>>>>
>>>>> How about a real decimal point (a dot) inside a footprint?
>>>>>
>>>>> Main reason I ask is for mounting hole designators. A client wants all
>>>>> this in metric dimensions and that will require fractions of a
>>>>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>>>>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>>>>> such and that's less understandable.
>>>>>
>>>>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
>>>> so .. why not 4MM5_DRILL?
>>>>
>>> I would write that as 4m5 m. The 4m5 is the number, the final m is
>>> the unit. I would also favour writing 1 mm^2 as 1u m^2, because I
>>> think that the multiplier 'prefixes' should apply to the number
>>> rather than to the unit, but that's not likely to please anyone.
>> 
>> or you could write 10na ot 10zb and confuse everyone :)
>> 
>
> I don't know what a and b are, but it's perfectly clear that
> we have 1e-8 of one and 1e-20 of the other.

I said it would confuse everyone. it confused me, I meant Zb 

ares and barns - two SI-ish  units of area.

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Jasen Betts wrote:
> On 2018-03-18, Jeroen Belleman <jeroen@nospam.please> wrote:
>> On 17/03/18 10:10, Robert Baer wrote:
>>> Joerg wrote:
>>>> Sorry for the occasional non-political post ...
>>>>
>>>> In the past I have seen special character issues with netlists across
>>>> foreign country boundaries. For example, in some countries they use a
>>>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>>>> some part numbers. That can blow a netlist out of the water.
>>>>
>>>> How about a real decimal point (a dot) inside a footprint?
>>>>
>>>> Main reason I ask is for mounting hole designators. A client wants all
>>>> this in metric dimensions and that will require fractions of a
>>>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>>>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>>>> such and that's less understandable.
>>>>
>>>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
>>> so .. why not 4MM5_DRILL?
>>>
>> I would write that as 4m5 m. The 4m5 is the number, the final m is
>> the unit. I would also favour writing 1 mm^2 as 1u m^2, because I
>> think that the multiplier 'prefixes' should apply to the number
>> rather than to the unit, but that's not likely to please anyone.
> 
> or you could write 10na ot 10zb and confuse everyone :)
> 

I don't know what a and b are, but it's perfectly clear that
we have 1e-8 of one and 1e-20 of the other.

Jeroen Belleman

On 2018-03-18, Jeroen Belleman <jeroen@nospam.please> wrote:
> On 17/03/18 10:10, Robert Baer wrote:
>> Joerg wrote:
>>> Sorry for the occasional non-political post ...
>>>
>>> In the past I have seen special character issues with netlists across
>>> foreign country boundaries. For example, in some countries they use a
>>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>>> some part numbers. That can blow a netlist out of the water.
>>>
>>> How about a real decimal point (a dot) inside a footprint?
>>>
>>> Main reason I ask is for mounting hole designators. A client wants all
>>> this in metric dimensions and that will require fractions of a
>>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>>> such and that's less understandable.
>>>
>>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
>> so .. why not 4MM5_DRILL?
>>
>
> I would write that as 4m5 m. The 4m5 is the number, the final m is
> the unit. I would also favour writing 1 mm^2 as 1u m^2, because I
> think that the multiplier 'prefixes' should apply to the number
> rather than to the unit, but that's not likely to please anyone.

or you could write 10na ot 10zb and confuse everyone :)

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On 18/03/18 18:17, John Larkin wrote:
> On Sun, 18 Mar 2018 16:31:22 +0100, Jeroen Belleman
> <jeroen@nospam.please> wrote:
>
>> On 17/03/18 10:10, Robert Baer wrote:
>>> Joerg wrote:
>>>> Sorry for the occasional non-political post ...
>>>>
>>>> In the past I have seen special character issues with netlists across
>>>> foreign country boundaries. For example, in some countries they use a
>>>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>>>> some part numbers. That can blow a netlist out of the water.
>>>>
>>>> How about a real decimal point (a dot) inside a footprint?
>>>>
>>>> Main reason I ask is for mounting hole designators. A client wants all
>>>> this in metric dimensions and that will require fractions of a
>>>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>>>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>>>> such and that's less understandable.
>>>>
>>>     On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
>>> so .. why not 4MM5_DRILL?
>>>
>>
>> I would write that as 4m5 m. The 4m5 is the number, the final m is
>> the unit.
>
> Would you dinension something   4m5 m   on a mechanical fab drawing?
> Would machinists know what that means?

No, I wouldn't, because I know it would only confuse. It's just
a way of writing numbers that I would have liked to see because
it seems like a clear and compact method to me.

In my line of work, the default unit is mm and tolerances are to be
specified according to ISO standards, so the the preferred marking
might be something like '4.5 H9'.

Jeroen Belleman

On Sun, 18 Mar 2018 16:31:22 +0100, Jeroen Belleman
<jeroen@nospam.please> wrote:

>On 17/03/18 10:10, Robert Baer wrote:
>> Joerg wrote:
>>> Sorry for the occasional non-political post ...
>>>
>>> In the past I have seen special character issues with netlists across
>>> foreign country boundaries. For example, in some countries they use a
>>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>>> some part numbers. That can blow a netlist out of the water.
>>>
>>> How about a real decimal point (a dot) inside a footprint?
>>>
>>> Main reason I ask is for mounting hole designators. A client wants all
>>> this in metric dimensions and that will require fractions of a
>>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>>> such and that's less understandable.
>>>
>>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
>> so .. why not 4MM5_DRILL?
>>
>
>I would write that as 4m5 m. The 4m5 is the number, the final m is
>the unit. 

Would you dinension something   4m5 m   on a mechanical fab drawing?
Would machinists know what that means?

Why not use proper scientific, SI units?  4.5 mm

A PCB symbol could be DRILL_4.5mm but a real PCB needs a total pad
stack, and usually that is native to the layout software.


This anti-decimal-point thing is weird.


-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

On 17/03/18 10:10, Robert Baer wrote:
> Joerg wrote:
>> Sorry for the occasional non-political post ...
>>
>> In the past I have seen special character issues with netlists across
>> foreign country boundaries. For example, in some countries they use a
>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>> some part numbers. That can blow a netlist out of the water.
>>
>> How about a real decimal point (a dot) inside a footprint?
>>
>> Main reason I ask is for mounting hole designators. A client wants all
>> this in metric dimensions and that will require fractions of a
>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>> such and that's less understandable.
>>
>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs ..
> so .. why not 4MM5_DRILL?
>

I would write that as 4m5 m. The 4m5 is the number, the final m is
the unit. I would also favour writing 1 mm^2 as 1u m^2, because I
think that the multiplier 'prefixes' should apply to the number
rather than to the unit, but that's not likely to please anyone.

Oh well.

Jeroen Belleman

On Friday, March 16, 2018 at 7:23:22 PM UTC-4, Tim Williams wrote:
> <gnuarm.deletethisbit@gmail.com> wrote in message 
> news:f1d89cde-e4e5-4e53-880c-0065ae1081f5@googlegroups.com...
> >
> > And there are still issues with using spaces in file names.  You may not 
> > encounter it very often, but it happens enough that I don't use them.
> >
> > Is_there_something_about_underscores_that_you_dont_like? 
> > Even-dashes-work-a-treat.
> >
> > Rick C.
> 
> Proving my point -- underscores and dashes are hard to read and look ugly as 
> sin.

If you can't read what I wrote, you need new glasses.  Heck, half the crap I have to read is much less legible than well formed text with underscores in place of spaces.  

I don't really give a rat's rear what you think is ugly.  I think functional is beautiful and spaces screw up functionality, so therefore are ugly as all get out in a file name.  

So here is a file name starting with the word here which is already in this sentence here which makes it very hard to tell what this here file name is exactly.  So what is the file name?  See, even humans can't properly cope with spaces in file names. 

Rick C. 

PS For extra credit, what is the file extension?  Are spaces allowed there as well?  here.space and more

On 2018-03-17, Robert Baer <robertbaer@localnet.com> wrote:
> Joerg wrote:
>> Sorry for the occasional non-political post ...
>>
>> In the past I have seen special character issues with netlists across
>> foreign country boundaries. For example, in some countries they use a
>> comma as the decimal "point" and NXP also has those dreaded "...,215" in
>> some part numbers. That can blow a netlist out of the water.
>>
>> How about a real decimal point (a dot) inside a footprint?
>>
>> Main reason I ask is for mounting hole designators. A client wants all
>> this in metric dimensions and that will require fractions of a
>> millimeter. For clarity I'd like to list that as "4.5MM_DRILL" footprint
>> or similar. If dots are not allowed I could only use 4500UM_DRILL" or
>> such and that's less understandable.
>>
>    On parts, 4n5F is the same as 4.5nF; 7M13Meg the same as 7.13Megs .. 
> so .. why not 4MM5_DRILL?

That's not actually a pattern.
where does the exponent go?
where doest he unit go?
you give 3 different examples.

On actual parts the markings are 452 and 7134


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