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Can you please help me getting width of theese golden fingers and what those text in red rectangle means?

enter image description here

It is M.2 connector with E key.

filimonic
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    I believe (but am not certain, hence why this isn't an answer) you've circled two different things. The top line is the dimension, there are thirty-four fingers each 0.35±0.04 mm wide. The bottom line is a mark I've seen on many engineering drawings but never did know what exactly it means (and it's never come up), but I think it's not directly related to the top line, which is merely a dimension like any other. – Hearth Sep 30 '22 at 16:47
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    The circle-with-a-cross box is something to do with [True Position – Position Tolerance](https://www.gdandtbasics.com/true-position). – Andrew Morton Sep 30 '22 at 16:50
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    The bottom left symbol in the red box is *true position*. I understand it when it is used for holes, but not on this drawing. https://fractory.com/true-position-gdt/ – Mattman944 Sep 30 '22 at 16:50
  • Thanks, @AndrewMorton . I thought it was gold-plating specs. – filimonic Sep 30 '22 at 16:54
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    @Mattman944 Do you think that maybe it means that the position tolerance for the whole group of contacts is 0.15 mm? Especially as the tolerance for the width of the connector is shown as +/-0.15 mm? – Andrew Morton Sep 30 '22 at 16:54
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    @AndrewMorton - Yes, something like that. *Each finger* must be within 0.15 mm of it's theoretical position relative to the datums listed (letters in square boxes). It also forbids tolerance accumulation as you go down the row of fingers. – Mattman944 Sep 30 '22 at 17:08
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    It's not technically wrong, but I suggest using "gold" or (better) "gold-plated" for the adjective describing the fingers. "Golden" *can* mean "made of gold" but more often means "gold colored". – Spehro Pefhany Sep 30 '22 at 21:52

2 Answers2

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The text in the red box means that that side has 34 contacts, each one is 0.35mm +/- 0.04mm wide, with center spacing at 0.5mm. Each contact extends 2mm from the end of the board. The reason they're not shown going all the way down to the bottom is because of the board bevel, which is specified at 20 +/- 5 degrees to a minimum final thickness of 0.2mm, which results in a bare area 0.3mm +/- 0.25mm in the vertical direction in your drawing.

Edit: I just spoke with the mechanical engineers and they confirmed what @Mattman944 said: the center of each contact must be within 0.15mm of its calculated position relative to the datums A, B, and C, which is the midplane of the card, instead of position relative to the next contact or some other reference point.

vir
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    This is part of Geometric Measuring and Tolerencing, with a guide to the symbols at [wikipedia](https://en.wikipedia.org/wiki/Geometric_dimensioning_and_tolerancing). The cross hair means "positioning", the number is the tolerence, and CBA show the datums in order of importance. – jonathanjo Sep 30 '22 at 17:32
  • Can you help me spot the C datum? – Bergi Oct 01 '22 at 20:22
  • The center spacing of .5mm is not part of the text in the red box, is it? – Bergi Oct 01 '22 at 20:24
  • You should have a side view that shows the C datum as the midplane of the card. The contact pitch is not part of the text in the red box. – vir Oct 05 '22 at 17:26
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  • The pitch between contacts is 0.50 mm.
  • There are 34 contacts.
  • The contacts are 0.35 mm wide ±0.04 mm.

I'm afraid I can't help with the rest of the red box.

Transistor
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