Pickett N4-T & N4P-T Vector Log

The Pickett N4 family was produced in the United States since 1959 until 1975. Fabricated all aluminum coated with a thin plastic coat, where scales are photo printed, with a flat nylon indicator screwed to white plastic frames, and everything held with metallic braces. The N4 family was fabricated in two sizes: the N4, a 12 inches long (10 inches scales) and the N4P, the pocket size 7.5 inches long (5 inches scales), and in two colors N4-ES and N4p-ES (eye saver yellow), and N4-T and N4P-T (traditional white)

The N4 family is the most powerful Pickett slide rule and one of the most powerful ever made worldwide, along with the Flying Fish 1003 made in Shanghai in 1978 . Designed with 34 real scales (27 nominal) it is the rule for scientist and Engineers. The scales on the N4 family are: ³√ #1, ³√ #2, ³√ #3, DF [ CF, CIF, T1, T2, ST, S Cos, CI, C ] D, DI, √ #1, √#2 on the front face, and LL1+.00D/-.00D, LL2+.0D/-.0D, DF/m [ CF/m, TH, SH, Ln, L, CI, C ] D, LL3+.D/-.D, LL4+D./-D on the back face. Some of these scales are double: LL#, T, √#, ³√ #, SH. It is noticeable that the Tangent scale T runs from 5.8^o to 84.3^o , and it is split in two parts. The sine hyperbolic scale SH runs from 0.10 to 3.0 and is also split in two. The scales Ln and L share also the same line. Another interesting characteristic of this rule is the presence of folded scales in both sides of the rule. On the front face are the standard DF-CF begining and ending at pi, and on the back face are the modified DF/m-CF/m, beginning and ending at 2.3.

According with the kind of logos on these rules, I conclude that the N4-T was manufactured between 1962 and 1964, and the N4P-T was between 1966 and 1970.

Here is a link to a wonderful simulation of the N4:

http://www.antiquark.com/sliderule/sim/n4es/virtual-n4es.html

I wanted to compare the first Model 4 - 1947 design, with the last Model N4 - 1959 design. Both models have the same scales but the distribution of these changed. Also the original design had no grouped scales, the last one did. Here are together to compare:

Click on the next links to see professional panoramic pictures of the N4-T and N4P-T models.

N4-T

https://www.sliderulemuseum.com/Pickett/Pickett_N4-T_N600-T_NOS_DualBaseTwinPack_N4.jpg

N4P-T

https://www.sliderulemuseum.com/Pickett/Pickett_Model_N4P-T_Vectorlog_NIB_GiftOfLeroyHauslerCollection.jpg

References:

• Robinson, Bill: Hyperbolic Slide Rule Archive. https://osgalleries.org/hyperbolic/index.html