International Slide Rule Museum has some information. Hope it helps. May not be what you want. ...

Hello Everone,Does anyone have any information on the dating of Picketts by initial manufacture of Model Name/Numbere.g when did the following first appear?Pickett Deci-Point  (Model 1)Pickett Model 2 Dual Base ...

Message topic "ST scale endpoint" includes the following that I moved to this new message topic.>> For example, I have referenced the Pickett N-16-ES image ...> Are there examples for ...

>> For example, I have referenced the Pickett N-16-ES image that shows 5.74 at the index, with no ST scale mark at that value> Are there examples for the use ...

Hi Rick, Are there examples for the use of the ST / S / T scales in its ...

Thanks to all that responded, and I think there is enough here to address my original issue -- It appears that different manufacturers have used different math to generate their ...

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It's explained on Wikipedia:  https://en.wikipedia.org/wiki/Brevet%C3%A9_SGDGBreveté SGDG was a French type of patent that ceased to exist in 1968. The name was a common abbreviation for "Breveté Sans Garantie Du Gouvernement“ (patent without government guarantees).France and Belgium maintained a ...

Hello Meine,In fact, it is the patent that is "without government guarantees".Gabriel

This is the same on the Graphoplex 690, 640, 620d, 612 and 615.I guess it means that the measurements are not guaranteed by anygovernment office, like we now have ISO ...

I'm not sure if this is a slide rule per se, but it seems to be in the same vein.https://www.facebook.com/marketplace/item/3792388024209327/?ref=saved&referral_code=null

Hi Robert, A copy of the Graphoplex 690/691/692 manual (in French) ...

Dear All,There is a Graphoplex logo on the right side of the 690a model.I can see it says "MADE IN FRANCE".But I can not decipher what the line directly above ...

Andreas,The citation for the errors is given in the footnote at the bottom of page 63.Best, Tom W.

Tom, when I read on the cited pages I find the sentence (starts onbottom of page 61) "The SRT scale is a C scale whose marks representnumbers of degrees ranging ...

Andreas,The ST scale is generally stressed for the trigonometric functions of small angles.However, looking at the Deci-lon manual (pages 62-63), it points out that when using the radians approach, the ...

With respect to minutes:180/pi: 43.77(s+t)/2: 43.49sin: 44.35tan: 42.64On the Nestler 0370 it is either (s+t)/2 or 180/pi. But if it is notvisible anyway, does it matter then? I needed a ...

FF1003: pretty obvious it is 180/pi. I also did not find additionaltickmarks for 180/pi.For old wooden German slide rules: Quite hard to say. Interestingly atleast Nestler and Faber seem to ...

I think I found a way to check the Thornton:The tick of tan 44.6 lies clearly left of ST 0.565 as it does on theGraphoplex but not on the Aristo. ...

I rechecked more carefully. On the Aristo Studio it is quite obvious180/pi. The Studio also does not have additional tickmarks for 180/pi.The Thornton 221 is difficult to guess for me, ...