HOME Relay, Ricoh, San-ai Keiki Co. group
Includes Exported and Re-Branded U.S. Models

Relay slide rules were manufactured in post-war Japan, originally branded NIKKEI, by Nippon (Japan) Slide Rule Company (1948 to 1950).. The company then became San-Ai Kekki Ltd. (1950 to 1958), exporting slide rules to the USA as Relay Industries. Became San-Ai Measuring Instruments (1958 to 1963). In April of 1963, the San-ai Group joined with Riken Optical Co. which was founded by Kiyoshi Ichimura in 1938 as Riken Kankoshi Co., Ltd which manufactured sensitized paper. This was later to become Ricoh Ltd, a Japanese conglomerate of companies.


KEEP ISRM FREE!
Ricoh supplied slide rules to the United States (Ricoh Industries, USA) and to European (Ricoh Europe SA in Switzerland) markets and re-branded slide rules to other companies. Brands Represented in this gallery:
AA, Alvin, Compass, Dietzgen, Eagle, Engineers, Jason, Lafayette, Lutz, Micronta, Nikkei, Olson, Omega, Pickett, Relay, Ricoh, Sans & Streiffe, SIC, Skyline, Staedtler Mars, TOBE, Toyo, Zodiak. Other known specimens are Dietzgen, Eagle, J.C.Penny, SELSI, and Wallace & Wallace. .

AA




AA SR815

ISRM 09.01.12.06
AA SR815 dcJK-4 (1961)
Made in Japan by Relay for AA, . Same as Relay 150
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA

Alvin & Company, Inc.

Note: ALVIN rebranded slide rules from the US, Japan and Denmark are all shown in this gallery
On 5/1/1962, a U.S. federal trademark registration was filed for ALVIN. This trademark is owned by Alvin & Company, Inc., Windsor, CT. The USPTO has given the ALVIN trademark serial number of 72143499. ALVIN is an United States importer, manufacturer and distributor of graphic arts, drafting, fine art, office, and craft products. It was founded in 1950 and is still in business.


ALVIN DSR-5 Demonstration Slide Rule

REF

ALVIN DSR-5 Demonstration Slide Rule
Made in USA for/by ALVIN. 1962 Trademark Logo
Front Scale: S, K, A [ B, CI, C ] D, L, T
Back Scale: unknown
Dimensions: 200cm[78.78 in] x 25cm[9.8in]
Note: This is a demonstration or teaching slide rule that was found in a New York City stationary shop.
Archive Photo - Pedlars World, UK


Alvin CS206 (Concise 300) Log Log

22.05.06.07

Alvin CS206 (Concise 300) Log Log
Made in Japan by Concise - 11.2cm Dia
Front Scale: K, A, D ( C, CI, B, L )
Back Scale: LL3, LL2, D ( C, S Cos, T1 Cot1, T2 Cot2, ST )
Gift Of Nancy Ulrich, of Denver, Colorado. Ted Ulrich Collection
Theodore ("Ted") A. Ulrich was born in Spokane, Washington and moved with his family to Ft. Collins six months later. Attending schools in both Ft. Collins and Boulder, Ted graduated with the Boulder HS class of 1961. Ted received an appointment to the United States Merchant Marine Academy, Kings Point, NY. He graduated from Kings Point in August of 1965.:Ted served his active duty in the Port of New York. He then enrolled in Fordham University (NY) School of Law and graduated in the class of 1970.Ted also served as Law Clerk to the Hon. John M. Canella of the Southern District of New York. Ted joined the law firm of Cadwalader, Wickersham and Taft as an Admiralty and International lawyer, rising to partner, and remained with that firm for twenty-four years. Ted accepted a position with Popham Haik, a Denver office of the Minneapolis-based firm. Ted's many hobbies included woodworking and ship modeling. He crafted several ship models, called "scratch built". The garnered him an award for that model. Ted met Nancy Allison at a Kings Point social event in late February 1964 and were married on May 30, 1966 at Roslyn, New York. Look for other slide rules from the Ted Urlich collection in the ISRM galleries.


ALVIN No.222P 5.5-in (re-branded X-Act)

ISRM 09.01.12.05
ALVIN No.222P 5.5-in (re-branded X-Act)
Made by Denmark - Similar to UTO models, but cursor not interchangeable.
Front Scale: 5.5in // K, A[ B, CI, C ] D, L
Back Scale: [ S, ST, T ]
Donated by david Hecht, Alexandria, VA


ALVIN 1150 Elite Desi Log (1960)

ISRM 13.12.03.01
ALVIN 1150 Elite Desi Log
Made in Japan by Relay/Ricoh (dc I.K-4) for ALVIN
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Material: Plastic laminated bamboo. All plastic cursor, Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, ST, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Multilined Cursor: Kw, HP, etc.
Original Owner: (Marked in sleeve flap) Lou Lotto, 39 Temple Road, Waltham, Mass. Te: 3-5308
Note that the Model name here is DESI LOG rather than DECI LOG (short for Decimal Log). This was an obvious misspelling by the Japanese firm. Sometime after the first release in 1960, they fixed the problem. The 1969 model below has been corected. Look at this graphic comparing the two slide rules.


ALVIN 1150 Elite Deci Log (1969)

S571
ALVIN 1150 Elite Deci log
Made in Japan by Relay/Ricoh (RS-6) for ALVIN
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, ST, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Multilined Cursor: Kw, HP, etc.


ALVIN 1151 Elite MultiLog

ISRM 21.10.06.02
ALVIN 1151 Elite MultiLog dcR.S.-6 (1969)
Made in Japan by Relay/Ricoh for ALVIN
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale (Extended): LL0, L, K, A [ B, S Cos ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (Extended): LL1, LL2, LL3, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Multilined Cursor: Kw, HP, etc.
Note: Same as SIC Relay 151, Lafayette 99-70559 and Sans & Streiffe 312


ALVIN 1157 Elite Vector Deci-Trig Log Log

REF
ALVIN 1157 Elite Vector Deci-Trig Log Log
Made in Japan by Relay/Ricoh for ALVIN
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale: Sr, Sθ , P', [Q, CF, CI, C ] D, DF, LL2, LL3
Back Scale (Extended): Sh2, Sh1. A [ B, K, Th, C ] D, Tr1, Tr2, db
Multilined Cursor: Kw, HP, etc.
Note: Similiar to SIC Relay 1570
Scan provided by Steve Seale Collection, Nashville, Tennessee.

Compass Instrument and Optical Company

Compass was located at 268 Fourth Ave. New York 10, New York
They rebranded slide rules from the US as well as Japan. The first few shown in this gallery were made in the U.S.A. After WWII Compass started rebranding the Ricoh line of slide rules.


Compass 4" dia Midget (Gilson) Circular
ISRM 10.09.14.02
Compass Midget (Gilson - 1931, 1936 Copyrights) - 10.2cm dia
Made in USA for Compass by Gilson Slide Rule Co., Stuart, Florida
Front Scales
C,CI,A,K,Log,LL1,LL2,LL3,LL4,
Back Scales
Binary, Fraction,Drill,Thread, Millimeter
Donated by David Viscusi, Carlsbad, California
David bought this slide rule when he was a Drafting apprentice at General Electric, Schenectady NY (1971). Already well used, it was purchased for $5 from a retiring engineer that helped design Large Steam Turbine Generators. It helped get him through his BSME night courses. David is now the Engineering & Technical Services Supervisor at Gemological Institute of America (GIA)

Compass 8" Binary (Gilson) Circular

ISRM 17.08.24.01
Compass 8" Binary Circular (Gilson - 1931, 1936 Copyrights) - 21.4cm dia
Made in USA for Compass by Gilson Slide Rule Co., Stuart, Florida
Front Scales
C,CI,A,K,Log,LL1,LL2,LL3,LL4,
Back Scales
Binary, Fraction,Drill,Thread, Millimeter


Charvoz-Roos SR-108 Dual Duplex
ISRM 17.08.24.04
Charvoz-Roos SR-108 Dual Duplex (Metal Braces)- c1946
Made in USA
Note: Scales set up as if it's a 10inch Scale: Front Scale: K, A [ B, S, T, C ] D, DI
Back Scale: Fraction-Decimal[ L, C2, C1 ] D1, D2, D
Manual 7.56Mb


REF Compass 403 (c1962)
Compass 403
Made in Japan by Relay/Ricoh
Front Scale: 10cm // A [ B, CI, C ] D || 5in
Back scale: [S, L, T ]
Back: Calculating Guide formulas
Scan provided by Cassou Olivier Collection


Compass 505 (1962)

ISRM 09.01.12.04
Compass 505 (Date Code K.K-4)
Made in Japan by Relay/Ricoh
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back scale: [S, L, T ]
Back: Calculating Guide formulas
Donated by David Hecht, Alexandria, Virginia


Compass 1018

ISRM 09.01.12.03
Compass 1018
Made in USA - NY - by Bruning. Shown here as rebranded for Compass.
Front Scale: 12.5cm // A [ B, CI, C ] D, K \\ 5in
Back Scale: [S, L, T ]
Back: Blank
Originally Owned by W. Hatch (marking on sleeve)
Donated by David Hecht, Alexandria, Virginia


Compass 1020

ISRM 18.07.11.13

Compass 1020
Made in USA - NY - by Bruning. Shown here as rebranded for Compass.
Front Scale: 25cm // A [ B, CI, C ] D, K \\ 10in
Back Scale: [S, L, T ]
Back: Equivalents per U.S. Bureau of Standards Circular No. 47
Gifted by Phil Stanley of Worcster, Massachussettes
Philip Stanley retired from engineering to become a full-time dealer in and appraiser of antique scientific instruments and tools as The Analytical Engine. He has written two books on antique measuring instruments, and numerous articles on instruments and technology, and has given several talks on these subjects. Phil appeared on the Antiques Road Show on PBS, as an appraiser, in 2012, 2013, 2014.


Compass 1315 (1967)

ISRM 13.05.19.02
Compass 1315 dc P.S-3 (1967)
Made in Japan by Relay/Ricoh
Front Scale: A [ B, CI, C ] D, K
Back Scale: [S, L, T ]
Back: Equivalents
Donated by Jeremiah Whitney, Louisville, Colorado
Jeremiah Wadsworth Whitney (1941- ) used this slide rule in his career as an Architect.He graduated with a B.Arch degree from Yale University in 1963, and as part of the Officer Candidate School, he spent the next 5 years (1963-1968) as a commissioned officer, in the U.S. Naval Reserves, achieving the rank of Lieutenant, He received his MS.Architecture from Yale in 1971, then relocated to Colorado and specialized in residential design for developers. Photo taken by ISRM in 2013.


S231 Compass 1321 Log Log
Compass 1321 Log Log
Made in Japan (FK1) for Compass Instruments
Front Scale: LL0, LL00, A [ B, K, CI C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2


Compass 1321 Log Log

ISRM 09.01.12.02
Compass 1321 Log Log
Made in Japan (PS-4) for Compass Instruments
Front Scale: LL0, LL00, A [ B, K, CI C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA

Eagle - Texas-Asiatic Import Company, Dallas, Texas.

Texas-Asiatic Import Company was located at 2127 Fort Worth Ave, Dallas 11, Texas USA. Originally the Eagle Technical Company, a sole proprietorship, founded by Byron Eugene Miller, who was a college graduate with a degree in geophysical engineering. Beginning in 1955, he imported and distributed surveying and drafting equipment from Japan, specifically from Tokyo Sokkei Co, Ltd and Zuiho Optical Instrument Company. as well as rebranded slide rules from Ricoh. The Texas-Asiatic Import Company was frequently listed in trade directories from at least 1957-1967, and was embroiled in a law suit with US. Customs on tariffs in 1969 over misunderstanding of wholesale F.O.B an ex-factory prices for transcactions with Tokyo Sokkei Co, Ltd and Zuiho Optical Instrument Company in 1962.


Eagle No. 201 Log Log Speedmaster (1960)

ISRM 22.07.06.01

Eagle No. 201 Log Log Speedmaster dc I.S-2 (1960)
Made in Japan by Relay/Ricoh - same as an Omega (Relay) 151.
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale (extended): LL0-, L, K, A [ B, S, ST, T, C ] D, DI, P, LL0
Back Scale (extended): LL1-, LL2-, LL3-, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Single hairlined Cursor, early narrow blocks.
Note: Does not have the red Cos, Cot trig scales found on the Ricoh 151 and SIC 151
It was new old stock, and until scanned by ISRM was in a sealed polybag.
Gift of Cindy Tate of Bozeman, Montana. Victor B. Tate II (1941 - 2021) collection.


Eagle No.202 Pocket Bamboo Slide Rule
REF
Eagle No.202 Pocket Bamboo Slide Rule
Made in Japan
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back Scale: [ S, L, T ]
Back: Conversion Chart
Archive photo from eBay listing

ENGINEERS - Crawford Engineering Equipment Co.(1956)
c1956. later Lewis M. Crawford & Sons, (1962), Joanna, South Carolina

March 1956 Dec 1962


Engineers No.1050
ISRM 09.01.12.07
Engineers No.1050 dc KK-4 (1960)
Made in Japan by Relay
Front Scale: 25cm // K, A, [ B, CI, C ] D, L || 10in
Back Scale: Equivalents [ S, S&T, T ]
Donated by David Hecht, Alexandria, VA


Engineers No.1500 Duplex Decitrig Log/Log

ISRM 09.01.12.08
Engineers No.1500 Duplex Decitrig Log/Log dcLS-4 (1963)
Made in Japan by Relay, 21 scales, same a Relay 150
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, S T, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Engineers No.1510 Multi-Log

REF
Engineers No.1510 Multi-Log
Made in Japan by Relay, 21 scales, same as Relay 150, SIC 1510
Front Scale (extended): LL0, L, K, A [ B, S Cos ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (extended): LL1, LL2, LL3, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Note: Same as SIC Relay 151, Lafayette 99-70559 and Sans & Streiffe 312
Archive photo - Ebay Listing


P099 Engineers No.5500

REF P099
Engineers No.5500 - Open Duplex
Made in Japan - code KK-4
Front Scale: A, [ B, S, T, C ] D, K
Back Scale: DF [ CF, CI, C ] D, L


Engineers No.5500-S Duplex (1969)

ISRM 22.03.01.83
Engineers No.5500-S dcRS-9
Made in Japan by Ricoh for a company called Engineers (Slide Rules?)
Front Scale: K, A, [ B, S, T, C ] D, DI
Back Scale: DF [ CF, CIF, CI, C ] D, L
Gift from the Philip E. Stanley Collection.

Jason Empire, Kansas City, Kansas


Richard and Carol Levine
Richard M. Levin - (1925-2014) Co-founded Jason/Empire with his father Jake Levin. He served two and half years in the US Army and was wounded at the initial battle of Leyte, Philippines, in 1944, receiving the Combat Infantryman Award and the Purple Heart. He returned to college in 1945. Richard spent two years working in Chicago after graduating from the Wharton School in 1947. The Jason/Empire was co-founded in 1949 initially as "Jake and Son". Their early optics customers included jewelry stores along with then popular catalog showrooms. The name was soon shortened and formalized to "Jason" with headquarters offices in Kansas City, Missouri. Empire, which evolved as part of the firm's name, was a brand of products sold by the firm in its early years. Re-branded slide rules were added to their offerings during the 1960s. Richard was the CEO. The main products the company sold were binoculars, telescopes, microscopes and weather instruments; later the company specialized in tennis products. After taking the company public in 1969, Richard arranged the sale of Jason/Empire to the Carlson Company of Minneapolis in 1977 the Jason headquarters remained in Kansas City. The company ultimately ending up as part of Bushnell Optics in 1992. Note: Richard Levin and his wife, collected of painting from unknown American artists. In 2015, one year after his death, A collection of 33 American paintings amassed over half a century sold for $2.32 million at an auction in Chicago, shattering presale estimates.
Jason 1967 Catalog Page 230 Slide Rules Section Scan By Jorge Lemaitre


Jason 800

REF S472
Jason 800
Made in Japan for Jason by Relay/Ricoh
Front Scale: A [ B, CI, C ] D, K
Back Scale: [ S, L, T ]
Back: Equivalents




Jason 801 Mannheim Trig (1966)

ISRM 19.03.25.01
Jason 801 Mannheim Trig
Made in Japan by Relay/Ricoh 28 scales - Date Code O.S-4 (1966)
Front Scale: 25cm // K, A [ B, CI, C ] D, L || 10in
Back Scale: [ S, S&T, T ]
Back: Equivalents
Donated by Michael Banks


Jason 802 Decitrig Log/Log

ISRM 09.01.12.09
Jason 802 Decitrig Log/Log dcLS-4 (1963)
Made in Japan by Relay,, 21 scales
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, S T, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Jason 803 Log Log Duplex Deci-Trig (1965)

ISRM 14.02.13.01
Jason 803 Log Log Duplex Deci-Trig
Made in Japan by Relay/Ricoh 28 scales - Date Code N.S-3
Front Scale (extended): LL/0, L, K, A [ B, S Cos, ST Cos, T Cot, C ] D, DI, P, LL0
Back Scale (extended): LL/1, LL/2, LL/3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1
Original owner(Written inside flap of sleeve): Brian Keith, 316 Alumni, P.O. Box 1823
Note: Cursor bars were yellowed and replaced with whiter ones from a SIC cursor


Lafayette Radio Corp.; New York, N.Y., 100 Sixth Avenue (Syosset)

1960 Catalog, Slide Rule Page
Founded 1920 as Wholesale Radio Service Co. Inc. Trade names LaFayette, Trutest.The company sold radio sets, amateur radio equipment, citizen's band (CB) radios, and other communications equipment, as well as electronic components and even tools, through retail outlets as well as by mail-order. An USA mail order electronics retailer that also had large stores in some major cities, in the early day's mainly supplied electronic parts but later had a range of electronc goods including a range of products with their own brandname and with time the ration of own branded products did increase, but with the possible exception of some early radio models they are not believed to have made any these products themselves. In the 50's and 60's the Lafayette branded product where perceived to have been of at the least reasonable quality and often of a very good quality indeed but during the last years of the operation the products had by and large become the same budget Asian sourced stuff that everyone else was selling. Taken over by Radio Shack in the early 1970's and slowly integrated into that operation. Colloquially known as Lafy, note that there where a number of electronics manufacturers called Lafayette that where not related to this company. Ref: audiotools.com


Lafayette F341 Duplex Log Log Decitrig

ISRM 09.01.12.10
Lafayette F341 Duplex Log Log Decitrig
Made in Japan by Relay/Ricoh 21 scales (same as Ricoh 150)
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, S T, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Original owner, marked on SR: T. Zidank Dept 72
Donated by David Hecht, Alexandria, VA


Lafayette F341 Duplex Log Log Trig

ISRM 10.09.14.01
Lafayette F341 Duplex Log Log Trig
Made in Japan by Relay/Ricoh - date code I.K-3 (1960)
Front Scale (Trig scales:Deg-Min-Sec)
LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Original owner, marked on case: Wayne Evans
Donated by Ed Millis,Dallas, TX
Note: A very astute collector had found this F341 and wrote ISRM saying that the description was wrong because the trig scales were in degree, minutes and seconds, rather than decimal degrees found on decitrig models. See the Lafayette F341 above. As it turns out we were both correct and Lafayette (or Ricoh) changed the scales set and kept the model number. Ed donated it to ISRM for others to enjoy.


Lafayette F-381

REF S025
Lafayette F-381 - Closed simplex
OEM Japan for U.S. company Radio Shack
Front Scale: A [ B, CI, C ] D, K
Back Scale: [ S, L, T ]
Back: Conversion Chart


Lafayette F-382 (Concise 270)

REF C32
Lafayette F-382 (Concise 270)
Made in Japan by Concise - 11.2cm Dia
Front Scale: L, D ( C, CI, A, K )
Back Scale: DI, D ( S, T1, T2, ST )


Lafayette F-428 Log Log Duplex Deci-Trig

ISRM 21.02.21.01
Lafayette F-428 Log Log Duplex Deci-Trig
Made in Japan by Relay/Ricoh 25 scales - dc I.S-4 (1960)
Front Scale (extended): LL/0, L, K, A [ B, S, ST, T, C ] D, DI, P, LL0
Back Scale (extended): LL/1, LL/2, LL/3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1


Lafayette F-681 Decilog

REF P162
Lafayette F-681 Duplex Decilog  dc J.K-1 1961
OEM Japan Ricoh  for U.S. Company Lafayette - 24 scales
Front Scale: LL-0, L, K, A [ B, S, T, C ] D, DI, P, LL0
Back Scale: LL-1, LL-2, LL-3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1


Lafayette F-686 Vector log (1961)

ISRM 13.10.08.01


Leather Sleeve and Instructions 396KB PDF
Lafayette F-686 Vector log Date code J.K-1
OEM Japan Relay/Ricoh for U.S. Company Lafayette - 26 scales
Front Scale: Tr1. Tr2, P', P L, K, A [ B, S Cos, ST Sr, Se, C ] D, LL03, LL02, LL01
Back Scale: Sh1, Sh2, DF, A [ B, CF,CF, Th CI, C, LL1' ] D, LL3, LL2, db
Note the short, unique LL1' scale which was developed in the Lafayette laboratory to provide more accuracy when calculating logeN and ex when x is close to 1.
Gift of Marion Moon, of Orange, California.
Marion is a member of the Oughtred Society. Retired Software/Systems Engineer at Hughes Aircraft Co. BSEE University of Kanasas. Collects End-of-Era Slide rules from worldwide manufactures. Marion is a generous financial contribiutor and donor of slide rules and scans to the ISRM galleries and a supporter the educational inititives.


Lafayette F-686 Vector log (1963)

ISRM 19.12.05.02


Leather Sleeve and Instructions 396KB PDF
Lafayette F-686 Vector log Date code L.K-1
OEM Japan Relay/Ricoh for U.S. Company Lafayette - 26 scales
Front Scale: Tr1. Tr2, P', P L, K, A [ B, S Cos, ST Sr, Se, C ] D, LL03, LL02, LL01
Back Scale: Sh1, Sh2, DF, A [ B, CF,CF, Th CI, C, LL1' ] D, LL3, LL2, db
Note the short, unique LL1' scale which was developed in the Lafayette laboratory to provide more accuracy when calculating logeN and ex when x is close to 1.
Gift of A, Joseph Killian (WB6CHP) of Cedarville, California.
Joe acquired this slide rule while in high school. He received his B.S. in Physics from Harvey Mudd College and did graduate work in Atmospheric Physics at Desert Research Institute with UNR. He took contract work in the San Fracisco Bay area, and designed the IMSAI 8080 microcomputer. He worked at CoSine Communications as a Hardware department manager and at Zhone Technologies as a Sr. Hardware Architect.


Lafayette 99-7030 (1964)
ISRM 18.09.17.35
Lafayette 99-7030 dc M.K-3(1964)
OEM Japan Relay/Ricoh  for U.S. Company Lafayette - 9 scales
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back Scale: [ S, L, T ]
Back: Quick Computing aids
Advertising: (Sleeve) B.J. Centrilift (Made submersible Pumps).
Gifted by the Donald Bachelor Collection


Lafayette 99-70302 (1972)

ISRM 09.01.12.11
Lafayette 99-70302 (Date Code US-3)
Made in Japan by Relay/Ricoh (same as Ricoh 505)
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back scale: [S, L, T ]
Back: Calculating Guide formulas
Donated by David Hecht, Alexandria, Virginia


Lafayette 99-7031 Duplex Decitrig Log/Log (1965)

ISRM 09.01.12.12
Lafayette 99-7031 Duplex Decitrig Log/Log dcNS-2
Made in Japan by Relay/Ricoh , 21 scales
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, S T, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Lafayette 99-7127 (Concise 270)

ISRM 21.08.07.17

Lafayette 99-7127 (Concise 270)
Made in Japan by Concise - 10.2cm Dia
Front Scale: L, D ( C, CI, A, K )
Back Scale: DI, D ( S, T1, T2, ST )


Lafayette 99-70310 Duplex Decitrig Log/Log (1965)

ISRM 09.01.12.13
Lafayette 99-70310 Duplex Decitrig Log/Log dcNS-2
Made in Japan by Relay/Ricoh , 21 scales
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, S T, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Lafayette 99-70559 Decima-log (1966)

ISRM 22.08.01.01

Lafayette 99-7055 Decima-log - date code O.S-2
OEM Japan Relay/Ricoh (O.S-2) for U.S. Company Lafayette - 28 scales
Front Scale (extended): LL/0, L, K, A [ B, S Cos, ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (extended): LL/1, LL/2, LL/3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1
Gift of Margaret Geller of Watertown,Massachusettes.
Margaret Geller PhD (1947 -) is an astrophysicist at the Center for Astrophysics in Cambridge MA. She was an undergraduate at UC Berkeley and she received her PhD in physics from Princeton University in 1975. She used this slide rule when she was a graduate student; she studied the distribution of galaxies in an early catalog of nearby galaxies. Later she became known for her pioneering work on mapping the universe. She became a MacArthur Fellow in 1990 and was elected to the National Academy of Sciences in 1992. She is still exploring the largest patterns in nature by continuing her mapping work..


Lafayette 99-70559 Decima-log (1968)

ISRM 07.02.12.03
Lafayette 99-70559 Decima-log - date code Q.S-3
OEM Japan Relay/Ricoh (QS-3) for U.S. Company Lafayette - 28 scales
Front Scale (extended): LL/0, L, K, A [ B, S Cos, ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (extended): LL/1, LL/2, LL/3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1
Donated by Russell Fox, Anchorage, Alaska.
This slide rule was used by his father. He worked as an Electrical Engineer with BPA in Portland, Oregon. BPA and ASEA had a joint venture in providing electrical energy.


Lafayette 99-7099 Decimalog

REF P179
Lafayette 99-7099 Decima-log 1961
OEM Japan Relay/Ricoh  for U.S. Company Lafayette - 24 scales
Front Scale: LL-0, L, K, A [ B, S, T, C ] D, DI, P, LL0
Back Scale: LL-1, LL-2, LL-3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1


Lafayette 99-7102 Vector log (1966)

ISRM 19.04.14.01
Lafayette 99-7102 Vector Log dc O.S-1 (1966) (Same as F-686)
OEM Japan Relay/Ricoh for U.S. Company Lafayette - 27 scales
Front Scale: Tr1. Tr2, P', P L, K, A [ B, S Cos, ST Sr, Se, C ] D, LL03, LL02, LL01
Back Scale: Sh1, Sh2, DF, A [ B, CF,CF, Th CI, C, LL1' ] D, LL3, LL2, db,
Note the short, unique LL1' scale which was developed in the Lafayette laboratory to provide more accuracy when calculating logeN and ex when x is close to 1.
Manual 396KB PDF


Lafayette 99-71029 Vector log (1961)

REF
Lafayette 99-71029 Vector log - Date Code J.K-1
OEM Japan Relay/Ricoh for U.S. Company Lafayette - 26 scales
Front Scale: Tr1. Tr2, P', P [ Q, ST Sr, Se, C ] D, LL03, LL02, LL01
Back Scale: Sh1, Sh2, DF, A [ B, CF, Th CI, C ] D, LL3, LL2, db,
Archive - Scan courtesy of Rod Lovette Collection (UK)
Note the short, unique LL1' scale on the C scale which was developed in the Lafayette laboratory to provide more accuracy when calculating logeN and ex when x is close to 1.


Lafayette 99-7128 Decima-Dyne

ISRM 14.09.21.01
Lafayette 99-7128 Decimadyne
OEM Japan Relay/Ricoh for U.S. Company Lafayette - 24 scales
Front Scale: db -20-0 +0-20, DF [ CF, CIF, CI, C ] D, A
Back Scale: XC, XL, K [K1, S, T ] F2, F1, DI,
Gift Of Edward T. Wright, Odenton, Maryland.

Decima-Dyne Instructions (10.7MB) and Leather Sleeve

Lutz Co.

The Lutz Company was established in the early 1890s in Guttenberg, New Jersey, by German-born Kilian V. Lutz (1859-1916), and sold a range of drawing instruments and slide rules. The instructions from a pantograph states that the address of the firm was 65-71st Street in Guttenberg, and the telephone number was UNion 7-1920. The use of letters in the prefix of the phone number suggests a date of before 1963. Ref: Smithsonian math History Museum. Little history is known between 1916 through WWII. Lutz Co. were part of many entrepenuers that began distributing re-branded Ricoh slide slide rules after WWII.


Lutz 102-S U.S. 1961

ISRM 18.09.17.24
Lutz 102-S U.S.dcO.S-2 (1961)
Made in Japan by Ricoh. Marked "U.S."
Front Scale: S, K, A [ B, CI, C ] D, L, T
Back: Blank
Gift Of Donald S. Bachelor Collection.


Lutz 102-S U.S. Government 1974

ISRM 22.07.06.52
Lutz 102-S U.S.dcW.S-4 (1974)
Made in Japan by Ricoh. Marked "U.S. Government"
Front Scale: S, K, A [ B, CI, C ] D, L, T
Back: Blank
Gift Of Cindy Tate, Bozeman, Montana




Lutz 151P Multilog

ISRM 18.07.26.03

Lutz 151P Multilog
Made in Japan by Relay/Ricoh
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale (extended): LL0, L, K, A [ B, S Cos ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (extended): LL1, LL2, LL3, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Multilined Cursor: Kw, HP, etc.
Note: Same as SIC 151, ALVIN 1151, Lafayette 99-70559 and Sans & Streiffe 312
Gifted by William (Bill) A. Boas of Wray, Colorado See his bio in the Skyline brand catagory


Lutz 153 Trig
Need a specimen or scan of this model.
Lutz 153 Trig
Made in Japan by Relay/Ricoh
Front Scale: K, A [ B, S, ST, T C ] D, DI
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2



Lutz 252 U.S. dcMS-4 (1964)

ISRM 12.05.06.01

Expanded Family Biography of Wallace and Ruth Kane and daughter Ann Kilby (7.09MB)
See other slide rules from this talented family in the K&E, Post and Pickett Galleries.
Lutz 252 U.S. dcMS-4 (1964)
Made in Japan - Marked as U.S. (note red Cos, T, and Cot scales)
Front Scale: K, A [ B, T1 Cot1, T2 Cot2, ST ST, S Cos, ] D, DI
Back Scale: DF [ CF, CIF, CI, C ] D, L
Owned by Ruth Moira (Kilby) Kane (1921-2007). Donated in her memory by her daughter Anne Kilby, Kingston, Washington

Ruth Moira Kane (1950) with daughter Anne Kilby

Ruth was born in Seattle Washington, a child of academic tutors. The family moved to be part of the University of Denver. She acquired her first slide rule in high school and used it in physics while working as an assistant to Dr. Recht on the DU observatory. She went to UC Berkely, received her Masters and worked on her PhD. She was hired to work at the defense Laboratory at Livermore where she met her second husband, Wallace E. Kane (see the K&E gallery for his slide rule). After 1971 she did scientific editing and translated German articles. The couple relocated to the Puget Sound area in 1973 and Ruth became a public organizer to protect the local forests from over-development. She was an active musician, like her husband.


Lutz 252 U.S. Government (1963)

ISRM 12.06.04.06
Lutz 252 U.S. Government date code L.S.-1 (1963)
Made in Japan - Marked as U.S. Government
Front Scale: K, A [ B, T1, T2, ST, S] D, DI
Back Scale: DF [ CF, CIF, CI, C ] D, L
Donated by Stephanie H., Phoenix, Arizona - representing the Huang Collection, San Diego, California
The collector, who prefers to remain anonymous, obtained a B.S. degree in Physics from Taiwan's National Tsing Hua University in 1971. His love for computation has encouraged him to build a collection of slide rules, HP and TI calculators, as well as abaci, many displayed at ISRM.


Lutz 252 U.S.

ISRM 09.01.12.14
Lutz 252 U.S.
Made in Japan - Marked as U.S. (note red Cos, T, and Cot scales)
Front Scale: K, A [ B, T1 Cot1, , T2 Cot2, ST ST, , S Cos, ] D, DI
Back Scale: DF [ CF, CIF, CI, C ] D, L
Donated by David Hecht, Alexandria, VA


Lutz 300B U.S.

REF
Lutz 300B U.S.
Made in Japan - Marked as U.S.
Front Scale: Sh1, Sh2, Th, A [ B, T Cot, ST ST, S Cos, C ] D, DI, P, K
Back Scale: LL1,LL2, LL3, DF [ CF, CIF, L, CI, C ] D, LL3, LL2, LL1
Scan provided by the Steve Seale Collection, Nashville, Tennessee

Lutz 551 Duplex Log/Log
Need a specimen or scan of this model.
Lutz 551 Duplex Log/Log
Made in Japan - 24 scales
Front Scale: LL-0, L, K, A [ B, T, S, C ] D, DI, P, LL0
Back Scale: LL-1, LL-2, LL-3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1

Micronta (Radio Shack Brand)


During the late 50's to early 60's, Radio Shack was one of many electronic retailers and distributors who sold slide rules under their own brand. Radio Shack began selling slide rules in 1956 with just one offering, a Bruning 10 inch model. By 1957, they began selling their own line of slide rules under the Micronta label, a label that was used for test equipment, optics, and fine instruments. Most Micronta slide rules were made by San-Ai Kekki Ltd. of Japan which became the Ricoh/Relay Company. Others were made by Concise of Japan, a maker of circular slide rule, and Nestler of Germany. As more and more slide rules saturated the market during the 1960's, Radio Shack eventually dropped the Micronta line by 1965. Prior to this, they began selling other brands such as Pickett (1964 catalog), Otis King (1965 catalog), and eventually inexpensive plastic slide rules in the late 60's. By the early 70's, slide rules were phased out of Radio Shack's catalogs and replaced with electronic Slide Rule Calculators. Contributed by Lyman Lew


Micronta (Nestler) 14/52

ISRM 09.01.12.15
Micronta (Nestler) 14/52
Made in Germany by Nestler for US Brand Micronta
Note: All other Microntas were made by Ricoh
Front Scale: 10.5in // A [ B, C ] D
Back Scale: [ S, lg, T ]
Multilined cursor
Back: Equivalents (in English)
Donated by David Hecht, Alexandria, Virginia


Micronta 150 Duplex Decitrig Log/Log

ISRM 21.03.20.01
Micronta 150 Duplex Decitrig Log/Log
Made in Japan by Relay/Ricoh J.K-3- 21 scales dc I.K-3 (1960)
Front Scale (Trig scales:Deg-Min-Sec)
LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Original owner (on flap): W. Brunner, LTI, 100 Riverside Street.


Micronta 157 Electrical Duplex Vectorlog (1961)

ISRM 09.01.12.16
Micronta 157 Electrical Duplex Vectorlogdc dcJ.K-4
Made in Japan by Keikico San-ai (Ricoh) (1961)
Front Scale: Sr, SΘ, P', P [ Q, CF, CI, C ] D, DF, LL2, LL3
Back Scale: Sh2, Sh1, A [ B, K, Th, C ] D, Tr1, Tr2, db
Donated by David Hecht, Alexandria, VA


Micronta 505 (1959)

ISRM 09.01.12.17
Micronta 505 (Date Code H.K-2)
Made in Japan by Relay/Ricoh
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back scale: [S, L, T ]
Back: Calculating Guide formulas
Donated by David Hecht, Alexandria, Virginia


P054 Micronta 551 Duplex Log/Log
Micronta 551 Duplex Log/Log
Made in Japan - 24 scales
Front Scale: LL-0, L, K, A [ B, T, S, C ] D, DI, P, LL0
Back Scale: LL-1, LL-2, LL-3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1

Nikkei Nippon S.R.Co.



Nikkei No 150 (6 inch)
ISRM 20.04.01.133
Nikkei No 150
Made in Japan by Relay - Nikkei was the parent Company
Front Scale: DF [ CF CI, C ] D, A
Back Scale: [ T, L, S ] D
Gift Of Philip Stanley Collection


Nikkei No 260 (8 inch)

ISRM 22.05.16.02
Nikkei No 260
Made in Japan by Relay - Nikkei was the parent Company
Note: Aluminum backed bamboo stock
Front Scale: DF [ CF CI, C ] D, A
Back Scale: [ T, L, S ] D
Gift Of Debra Scheidt


Nikkei No 510 Log Log

REF
Nikkei No 510 Log Log
Made in Japan by Relay - Nikkei was the parent Company
Front Scale: S, K, A [ B, T Cot, S Cos, ST Cos, K, CI, C ] D, S, ST, T
Back Scale: L, K, DF [ CF, CIF, CI, C ] D, LL0, LL/0
Scan provided by Cory Fletcher

Olson Electronics, Akron, Ohio

260 South Forge St. Akron, Ohio USA based mail order retailer founded by brothers Irving, Sidney and Philip Olson in 1927 as Olson Radio and was based in Akron, Ohio. Interestingly the company had a chain of small retail stores spread across the USA, more like Radio Shack became later on, but their "catalogue" competitors like Lafayette usually had a few big stores in major metropolitan areas, also notable is that in the early years at the least a large part of their offerings was surplus stock and their catalogues where decidedly more downmarket than most, being printed on newspaper stock which in turn means that fewer copies have survived the ravages of time even though print runs hit the one million mark. In addition to developing their own lline of kits that were largely radio and audio related the company did sell audio and other electronic products under their own name including turntables and separates but their loudspeakers are the most fondly remembered by some although it is not known who was the OEM provider or providers for those, but in the 60's Olson's was still supplying USA made speaker components unlike most of cheaper electronics stuff that was by then largely imported from Japan. The company owned another firm originally called American Electronic Parts (AEPC) but later became known as Herald Electronics (H.E.)and was based in Chicago, Illinois, but H.E. became a sourcing operation for Olson's in addition to supplying independent dealers with OEM products under a variety of names, that H.E. was a wholesale supplier meant that Olson's ownership of the company was never much publicised. The budget nature of some of the company's goods made for some interesting products, for instance Olson was the company that bought us the "Vibra Sonic" spring reverb, normal spring reverbs use a flat sprung feather attached to a couple of transducers, but to cut costs the Vibra Sonic actually used a bedspring, the sound did not resemble a real reverb in any way but it did make a wonderful "sploink" sound when hard pressed. Olson Electronics was taken over by Teledyne (as was Frederick Post Slide Rules) at some point in the latter half of the 60's and that event marked the start of a decline in the company's fortunes, Teledyne started dumping low cost but high mark-up wares into the stores and overall quality of the in house brands in general went down. In the late 70's many of their smaller stores only stocked Olson branded products and locally sourced surplus stock, in addition the interest in surplus products declined with the miniaturisation of electronics and the growing purchasing power of consumer meant that kits were falling out of favour, the computer boom of the late 70's and early 80's seems to have been the final nail in the coffin since the people that had been electronic and ham radio enthusiasts a few years earlier were by that time spending their time and money on computers. The company appears to have gone out of business in the early/mid 1980's. Not to be confused with British concern Olson Electronics or a large number of small USA based companies that have appropriated the name since the demise of the original company. Ref: audiotools.com

Olson TL-366 (Ricoh 403)
ISRM 21.04.26.01
Olson TL-366 (Ricoh 403)
Made in Japan by Relay for Olson (electronic supply), Akron, Ohio.
Front Scale: 4in // A [ B,CI, C ] D
Back Scale: [ , S, ST, T ]
Back: Equivalents


Olson TL-373 (Relay 150)

REF S380
Olson TL-373 (Relay 150)
Made in Japan by Relay for Olson (electronic supply), Akron, Ohio.
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2


Olson TL-373 (Relay 150)

ISRM 09.01.12.18
Olson TL-373 (Relay 150) dc JK-4 (1961)
Made in Japan by Relay for Olson (electronic supply), Akron, Ohio.
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Olson TL-472 Electrical

ISRM 13.00.00.85
Olson TL-472 Electrical dc N.S-3 (1965 Shizuoka Factory)
Made in Japan by Relay/Ricoh for Olson (electronic supply), Akron, Ohio.
Front Scale: 25cm // E, Dynamo/motor, Volt, V, A(kw) [ B(hp), K, CI, C ] D, S, T || 10 in
Back Scale: [ LL3, LL2, LL1, L ]
Instructions 4.3MB PDF

Omega




Omega (Relay) 151 MultiLog (1961)

ISRM 21.08.12.07
Omega (Relay) 151 MultiLog dcJ.S-4(1961)
Made in Japan by Relay/Ricoh
Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale (extended): LL0-, L, K, A [ B, S, ST, T, C ] D, DI, P, LL0
Back Scale (extended): LL1-, LL2-, LL3-, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Single hairlined Cursor.
Note: Does not have the Cos, Cot trig scales found on the Ricoh 151 and SIC 151
Original Owner: Susan Graves (written on sleeve flap).


Omega DT-1015

REF S019
Omega DT-1015 Duplex
Made in Japan by Relay/Ricoh for Omega
Front Scale: K, A [ B, S, ST, T, C ] D, D1
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL2, LL3




Pickett B-1 Duplex Log Log - ca.1950

ISRM 18.04.06.01
Pickett B-1 Duplex Log Log - ca.1950
Made in Japan by Ricoh - The only Laminated Bamboo Pickett model 
Front Scale: LL0, L, A [ B, Cos S, SecT ST, T T, C ] D, sqr1, sqr2, LL0
Back - Scale: LL1, LL2, LL3, DF [ CF, CIF, CI, C] D, LL3, LL2, LL1
Gift of the Leroy G. Hausler Collection

Relay




Relay (no model number / date code) Pocket Mannheim

ISRM 22.07.06.76
Relay (no model number / date code) Pocket Mannheim
Made in Japan by Ricoh. Note: cursor is same as other Relay/Ricoh models
Note: Take a close look of the front scale labels. They are irregular like they were hand etched
Front Scale: 13cm // A, [ B, CI, C ] D, K || 5cm
Back Scale: [ S, L, T]
Back: Equivalents.
Gift Of Cindy Tate, Bozeman, Montana, Victor B. Tate collection.


Early Post WWII Japanese Pocket Mannheim Ricoh
ISRM 17.06.17.03
Early Post WWII Japanese Pocket Mannheim Ricoh
Made in Japan by Ricoh. Note: cursor is same as other Relay/Ricoh models
Note: Take a close look of the front scale labels. They are irregular like they were hand etched
Front Scale: ?// A, [ B, CI(faded off), C ] D || ?
Back Scale: [ S, L, T] Faded off
Back: Note: the cutouts for the trig scales. One side is different than all other Ricoh models.
Gift Of Phillip Rodley, UpperHutt, New Zealand


REF Relay 5 inch
Relay 5 inch - Closed simplex
Made in Japan
Front Scale: A [ B, C ] D, K
Back: Blank


S026 Relay 82
Relay 82 - Closed simplex
Made in Japan
Front Scale: A [ B, CI, C ] D, K
Back Scale: [ S, L, T ]
Back: Blank


S027 Relay 83
Relay 83 - Closed simplex
Made in Japan
Front Scale: K, DF [ CF, CI, C ] D, A
Back Scale: [ S, L, T ]
Back: blank


S171 Relay 102
Relay 102 - Closed simplex
Made in Japan by Keikico
Front Scale: A [ B, CI, C ] D, K
Back Scale: [ S, L, T ]
Back: Conversion Chart


Relay 102 (1960)

ISRM 14.01.10.79
Relay 102 I.K-2
Made in Japan by Keikico
Front Scale: A [ B, CI, C ] D, K
Back Scale: [ S, L, T ]
Back: Conversion Chart (not present on this specimen). See example below.


REF Ricoh 107 Electro
Ricoh 107 Electro - Closed simplex
Made in Japan by Ricoh, dc G.K-2 (1958)
Front Scale: 25cm // Dynamo, MotorLL1, A(KW) [ B(HP), CI, C ] D, LL2, Volt || 10in
Back Scale: Equivalents [ S, L, T ]
Scan by Olivier Cassou, France


Relay 150 Log-Log Decitrig (1951)

ISRM 09.01.12.19
Relay 150 Log-Log Decitrig dcB.K-4
Made in Japan by Relay (1951)
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Relay 153 Decitrig (1957)

ISRM 09.01.12.20
Relay 153 Decitrig dc HS-2
Made in Japan by Relay for S.I.C. (Scientific Intruments Inc) in Berkely, CA
Front Scale: K, A [ B, S, ST, T C ] D, DI
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


REF Relay 157 (Electrical)
Relay 157 - (Electrical) Duplex
Made in Japan by Keikico (Ricoh)
Front Scale: Sr, SΘ, P', P [ Q, CF, CI, C ] D, DF, LL2, LL3
Back Scale: Sh2, Sh1, A [ B, K, Th, C ] D, Tr1, Tr2, db
Archive - Atsushi Tomozawa collection (Japan)


REF Relay 158 (Electrical)
Relay 158 - (Electrical) Duplex
Made in Japan by Keikico (Ricoh)
Front Scale: Sh2, Sh1, Th, A [ BI, S, T, CI, C ] D, LL3, LL2, LL1
Back Scale: X2, X1, P2, P1 [ Q, Y, L, LX, I ] I, LΘ1, LΘ2, LY
Archive - Atsushi Tomozawa collection (Japan)


Relay 252 Trig

ISRM 11.11.10.03
Relay 252 Trig dc K.K-4 (1962)
Made in Japan by Ricoh
Front Scale: K, A [ B, T1, T2, ST, S] D, DI
Back Scale: DF [ CF, CIF, CI, C ] D, L

Relay 403 (MIOJ) 1950
ISRM 21.08.07.38
Relay 403 (MIOJ) dcZ.K-2 1950
Made in Japan by Ricoh
Front Scale: 4in // A [ B,CI, C ] D
Back Scale: [ , S, ST, T ]
Back: Equivalents
Gift of William Lisowski


Relay 403 4inch Pocket Slide Rule 1955
ISRM 14.07.22.07
Relay 403 4inch Pocket Slide Rule - dc D.K-3
Made in Japan by Ricoh
Front Scale: 4in // A, [ B, CI, C ] D || 10cm
Back Scale: [ S, L, T]
Back: Conversion Chart
Gift Of Phillip Rodley, UpperHutt, New Zealand


P134 Relay T-501
Relay T-501 - Closed simplex
Made in Japan
Front Scale: 13cm // A, [ B, CI, C ] D, K || 5in
Back Scale: [ S1, L, T1 ]
Back: Conversion Chart


Relay 505
ISRM 15.06.03.02
Relay 505 - Closed simplex
Made in Japan
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back Scale: [ S, L, T ]
Back: Conversion Chart
Gift of Lynne Powell, Lakewood, Colorado. She used it at Broomfield High School, in Broomfield, Colorado, between 1967-1970


REF Relay B-506
Relay B-506 - Closed simplex
Made in Japan
Front Scale: 13cm // DF [ CF, CI, C ] D, A || 5in
Back Scale: [ S1, L, T1 ]
Back: Conversion Chart
Scan by Olivier Cassou, France


Relay 550 (1951)

ISRM 09.01.12.21
Relay 550 dcBS-2 - Open Duplex
Made in Japan by Relay (1951)
Front Scale: A [ B, S1, T1, C ] D, L
Back Scale: DF [ CF, CI, C ] D, K
Donated by David Hecht, Alexandria, VA


Relay 602 (c1952)

ISRM 09.01.12.22
Lafayette_99-7032 (No Date Code)
Made in Japan by Relay/Ricoh (6 inch)
Front Scale: 15cm // K, A [ B, CI, C ] D, L || 6in
Back scale: [S, L, T ]
Back: Calculating Guide formulas
Donated by David Hecht, Alexandria, Virginia


Relay 605 Electro

REF
Relay 605 Electro
Made in Japan
Front Scale: 15cm // Dynamo-Mot, L1, A [ B, CI, C ] D, L2, Volts || 6in
Back Scale: [ S, L, T ]
Back: Equivalents Table
Archive - Atsushi Tomozawa collection (Japan)


Relay 651 Electro 8inch Duplex

ISRM 21.06.13.01
Relay 651 Electro 8inch Duplex dcE.K-1 (1956)
Made in Japan
Front Scale: L1, K, A [ B, S, T ] Dynamo-Motor, Volt
Back Scale: LL1, DF [ B, CF, CI, C ] D, LL2


Relay DE-1008

REF
Relay DE-1008
Made in Japan by Relay/Ricoh
Front Scale: Sh2, Sh1, Th, A [ BI, S, T, CI,C ] D, LL3, LL2, LL1
Back Scale: LL0, L, K, A [ B, S, ST, T, C ] D, DI, P, LL0
Scan provided by the Steve Seale Collection, Nashville, Tennessee


Relay DT-1015 Trig

ISRM 09.01.12.23
Relay DT-1015 Trig
Made in Japan by Relaybr> Front Scale: K, A [ B, S, ST, T C ] D, DI
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Relay DT-1065

REF
Relay DT-1065
Made in Japan by Relay/Ricoh
Front Scale: LL1,LL2, LL3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1
Back Scale: LL0, L, K, A [ B, S, ST, T, C ] D, DI, P, LL0
Scan provided by the Steve Seale Collection, Nashville, Tennessee


Relay T-1031 (1960)

ISRM 09.01.12.24
Relay T-1031 dcKK-4
Made in Japan by Relay - dcKK-4 (1960)
Front Scale: 25cm // K, A, [ B, CI, C ] D, L || 10in
Back Scale: Equivalents [ T2, T1, ST, S ]
Note: metal bridge (spring) on back is very corroded
Donated by David Hecht, Alexandria, VA

Ricoh




Ricoh 82 (8 inch version of 102) (1972)

ISRM 09.01.12.25
Ricoh 82 - Closed simplex dc US-5
Made in Japan by Ricoh, dc US-5 (1972)
Front Scale: A [ B, CI, C ] D, K
Back Scale: Equivalents [ S, L, T ]
Donated by David Hecht, Alexandria, VA


Ricoh 102 (10 inch version of 82)(1972)

ISRM 09.01.12.26
Ricoh 102 - Closed simplex dc US-5
Made in Japan by Ricoh,
Front Scale: A [ B, CI, C ] D, K
Back Scale: Equivalents [ S, L, T ]
Donated by David Hecht, Alexandria, VA


Ricoh 107 Electro

REF S091
Ricoh 107 Electro - Closed simplex
Made in Japan
Front Scale: E (Dynamo), V (volt), A (amp)[ B, K, CI, C ] D, S, T
Back Scale: [ LL3, LL2, LL1, L]
Back: Conversion Chart


Ricoh 116

REF
Ricoh 116 - Closed simplex
Made in Japan by Ricoh
Front Scale: 25cm // K, DF [ CF, CIF, CI, C ] D, A, DI || 10in
Back Scale: Equivalents [ T1, T2, L, S ]
Scan by Olivier Cassou, France


Ricoh 121 Log-Log

REF
Ricoh 121 Log-Log - Closed simplex
Made in Japan by Ricoh
Front Scale: 10in // S, T, A [ B, K, CI, C ] D, P || 25cm
Back Scale: Equivalents [ L, LL1, LL2, LL3 ]
Scan by Olivier Cassou, France


Ricoh 150 Duplex Decitrig Log/Log (1969)

REF S333
Ricoh 150 Duplex Decitrig Log/Log
Made in Japan by Relay/Ricoh, date code RS-3, 21 scales
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, S T, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2


Ricoh 151 MultiLog (1964)

ISRM 21.03.05.01


Ricoh 151 MultiLog - dcM.S-6.(1964)
Made in Japan by Relay/Ricoh - Same as SIC 151, ALVIN 1151, Lafayette 99-70559 and Sans & Streiffe 312. Dimensions: 35cm x 4.7cm x 0.6cm, 131gm
Front Scale (Extended): LL0, L, K, A [ B, S Cos ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (Extended): LL1, LL2, LL3, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Multilined Cursor: Kw, HP, etc.
Original Owner: Sheridan Tatsuno (written on sleeve flap and stamped on cursor). The ISRM curator was able to track down the owner.
Sheridan Tatsunolast used this slide rule while attending San Jose High School in California. The slide rule is dated 1964. He has a BA in Political Science from Yale University (1967-1972), an MA in Urban Planning from Harvard University (1975-1977) and an MA in Urban Studies from Occidental College (1971). Currently, Sheridan is a Silicon Valley strategist, serial entrepreneur, producer and writer of screenplays, novels and business books who focuses on VR storytelling for sustainable cities. He is co-launching a film studio and writing the Virtually San Francisco 9-novel series about VR real-world use cases: www.dreamscapeglobal.com Specialties: sustainable development, VR/AR use cases and business models, serial entrepreneur, screenwriting, filmmaking. From 2013, He has volunteered as the Curator of "San Francisco Rocks" which deals in economic empowerment, posting job openings, funding opportunities, art grants, exhibitions and events, and other news to enable cultural artists to build their businesses and generate revenues.


Ricoh 153 Trig (1961)

ISRM 09.01.12.27
Ricoh 153 Trig dc LS-2
Made in Japan by Ricoh
Front Scale: K, A [ B, S, ST, T C ] D, DI
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA


Ricoh 252 (1963)

ISRM 09.01.12.28
Ricoh 252 dcLS-4
Made in Japan by Ricoh
Front Scale: K, A [ B, T1 Cot1, , T2 Cot2, ST ST, , S Cos, ] D, DI
Back Scale: DF [ CF, CIF, CI, C ] D, L
Donated by David Hecht, Alexandria, VA


Ricoh 403 4inch Pocket Slide Rule 1968
ISRM 18.12.08.01
Ricoh 403 4inch Pocket Slide Rule - dc QS-2 (1968)
Made in Japan by Ricoh Kieki Co. Ltd.
Front Scale: 10cm // A, [ B, CI, C ] D
Back Scale: [ S, L, T]
Back: Conversion Chart
Back Promo: Legnano Italy
Gift Of Phillip Rodley, UpperHutt, New Zealand


Ricoh No. 514 5inch Pocket Slide Rule
ISRM 22.07.05.01
Ricoh No. 514 5inch Pocket Slide Rule
Made in Japan by Ricoh Kieki Co. Ltd.
Front Scale: 13cm // A, DF [ CF, CI, C ] D, A || 5in
Back Scale: [ T1, T2, L, S ]
Back: Conversion Chart
Gift Of Vince Alcouloumre of Richmond, California.


Ricoh 550

REF P105
Ricoh 550 - Open Duplex
Made in Japan by Relay - code NK-2
Front Scale: A, [ B, S, T, C ] D, K
Back Scale: DF [ CF, CI, C ] D, L


Ricoh 551 MultiLog (1969)

ISRM 21.06.21.01
Ricoh 551 MultiLog
Made in Japan by Relay/Ricoh - date code dcR.S-7
Dimensions: 17.5cm x 3.5cm x 0.6cm,
Front Scale (extended): LL0, L, K, A [ B, S Cos ST ST, T Cot, C ] D, DI, P, LL0
Back Scale (extended): LL1, LL2, LL3, DF [CF, CIF, CI, C ] D, LL3, LL2, LL1
Note: Pocket version of Ricoh 151 Multilog.

Sans & Streiffe Inc. - Brookfield, Illinois.

Sans & Streiffe of 8400 Brookfield Avenue and 565 W. Washington Blvd., Cook County, Brookfield, Illinois, was a US importer/distributor that sold or re-branded products mostly from Japan. Known products were listed as microscopes, binoculars and other optics including barometers, thermometers and hygrometers., Drawing instruments, slide rules and various other products were typical offerings. The USPTO company trademark was first used in 1951, registered in 1959, renewed in 1979 and expired in 2000. There is no clue on who the principle partners, "Sans" & "Streiffe" might have been. The small commercial building at that address was built in 1955 which was only 12 minutes away from Chicago Midway International Airport.. Arthur R. Hoff and William Diehl were listed as officers of the corporation in 1963. An Ed Overstreet was employed by Sans & Streiffe in 1957 and traveled to Japan to set up product lines.


S245 Sans & Streiffe_310
Sans & Streiffe 310
Made in Japan by Relay dc G.K-3 (1958) for Sans & Streiffe
Front Scale (extended): 25cm // K, A [ B, CI, C ] D, L || 10inch
Back Scale: [ S, S&T, T ]



Sans & Streiffe No. 311 Log Log

ISRM 17.08.24.02
Sans & Streiffe No. 311 Log Log (version 1)
Made in Japan by Relay dc I.S-2 (1960) for Sans & Streiffe
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, ST, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Original owner (Name marked inside flap): W.C. Franz K9KYF of Glenn Ellyn, Illinois
Gift Of Nancy Morris ot Tempe, Arizona. Dustin E. Morris Collection


Sans & Streiffe No. 311 Log Log

ISRM 12.09.25.02
Sans & Streiffe No. 311 Log Log (version 2)
Made in Japan by Relay dc P.S-2 (1967) for Sans & Streiffe
Front Scale: LL0, LL00, A [ B, K, CI, C ] D, S Cos, ST, T Cot
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Original owner (Name marked inside flap and initials on stock): H. Mayer


Sans & Streiffe 312

ISRM 22.02.25.01
Sans & Streiffe 312
Made in Japan by Relay dc J.S-4 (1961) for Sans & Streiffe
Front Scale: LL0, L, A [ B, S, ST, T, C ] D, DI, P, LL0
Back Scale: LL1, LL2, LL3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1

S.I.C.
These Ricoh manufactured Slide Rules have a large number of models so they have their own Sci.Inst.Co. SIC gallery


SKYLINE Distributors Denver, Colorado

Skyline Distributors was a Denver based company (as early as 1959) that specialized in electronics supply much like Radio Shack or Lafayette Electronics. and in surveying and drafting equipment. They ended their business in 1993 and the trademark name taken up by other companies. These two slide rules are the only known specimens of Skyline branded slide rules, both acquired by Bill Boas while living in the Denver area.


Skyline Technolog 151

ISRM 06.12.20.01

Skyline Technolog 151
Made in Japan by Relay for Skyline Distributors dc P.S-4 (1967)
Front Scale (extended): LL-0, L, K, A [ B, S Cos, ST ST, T COT, D ] D, DI, P, LL0
Back Scale (extended): LL-1, LL-2, LL-3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1
Gifted by William (Bill) Boas of Wray, Colorado.
Purchased in 1993 directly from the Skyline store in Denver before they ended the business

William (Bill) Augustus Boas, is an independent journalist and writer. Bill grew up in the Bronx, New York and served in the U.S. Navy from 1962 to 1966, on ships with the 2nd and 6th Fleets, and under Commander, Fleet Air Mediterranean at Naples, Italy. He worked as the Business Administrator of the American Academy of Dramatics Arts in 1968, and a press aide for a W. Averell Harriman political cause in 1969. He has been a correspondent for The Wall Street Journal, Business Week magazine, and United Press International as well as numerous regional general interest and trade periodicals. For his writing, he received an Honorary Citizenship of the State of Texas from Governor Price Daniel in 1961; a George Washington Honor Medal from the Freedom's Foundation at Valley Forge in 1964; and the 1982 Morton Margolin Prize for Distinguished Business Reporting from the Morton Margolin Trust administered by the College of Business Administration of the University of Denver. One of his interests was collecting slide rules, . He now lives in Wray, Colorado engaged in other writing and photography projects

Manual PDF Skyline No. 505 Relay dc H.K-4 (1959)
ISRM 18.07.26.04

Skyline No. 505 Relay dc H.K-4 (1959)
Made in Japan and rebranded for Skyline Distributors, Denver, Colorado
Front Scale: 13cm // A [ B, CI, C ] D, K || 5in
Back Scale: [ S, L, T ]
Back: Conversion Chart
Gifted by William (Bill) Boas of Wray, Colorado,
Bill Purchased this in 1993 directly from the Skyline store in Denver before they ended the business

Staedtler Mars

This slide rule was manufactured by Ricoh as an OEM and rebranded for the German market. It is listed here for reference and also appears in the Germany/Staedtler gallery.


Staedtler Mars 944-24 (1969)

REF
Staedtler Mars 944-24 - date code T.S.6
Made in Japan by Relay/Ricoh
Front Scale: LL0, L, K, A [ B, S Cos, ST ST, T Cot, C ] D, DI, P, LL0
Back Scale: LL1,LL2, LL3, DF [ CF, CIF, CI, C ] D, LL3, LL2, LL1
Scan provided by the Steve Seale Collection, Nashville, Tennessee

Tobe Deutschmann Laboratories, Canton, Massachussetts


Tobe Deutschmann Laboratories, aka Tobe Deutschmann Corporation (1929), and Deutschmann Tobe Laboratories, TDL, Inc.) was founded by Mr.Tobe C. Deutschmann, and had its beginnings as an electronic parts supplier, such as tuners; condenser analyzer; all-wave aerial filterizer; capacitors; condensers; etc. They were in business from the 1920's through the present.
Tobe Deutschmann was raised in Dorchester by German immigrant parents. At a very young age he distinguished himself in the field of avionics and radar. An early European trip in 1927 gave him amazing insights into the fledgling field. For three months, he studied radio communications as they applied to aircraft, and in doing so most of his time during that vacation was spent in the air. Friends who joined him on that trip nicknamed him the "Flying Deutschmann."The Canton Citizen 12-09-2017
Tobe talked himself into the radio business on a shoestring after the last the first world war, and made $68,000 in 1927 on condensers. But that year an engineer showed him how a filter would eliminate static and since then Tobe focused on electrical noise reduction in machinery and automotive applications to reduce radio signals interference. His business grew to 200 employees in 1928 but after the World war he was down to 40 workers, all engineers. During WWII the Army bought Tobe "Filteretts for their Willys- jeeps, and tacticle vehicles including tanks. By 1942 his sales were worth $5,000,000. The company, TDL, Inc, with Tobe C. Deutschmann Jr, of Dover, MA (Ham radio W1AT) as the president of the company was disolved in 2016.


TOBE (Ricoh 505) 1959
ISRM 20.01.10.101
TOBE (Ricoh 505) dcHK2(1959)
Made in Japan by Relay for TOBE, Norwood, Mass. Office.
Front Scale:
13cm // A [ B, CI, C ] D,
Back Scale: [S, ST, T ]
Gift Of Philip Stanley, Worchester, MA.


TOBE (Ricoh 505)
REF
TOBE (Ricoh 505)
Made in Japan by Relay for Tobe Deutschmann Laboratories, Norwood, Mass. Office.
Front Scale:
13cm // A [ B, CI, C ] D,
Back Scale: [S, ST, T ]
Archive - Photos by Stephen Kay of Solon, Ohio

Toyo

Toyo Specialized Business Development Co.
Toyo Tokusen-Kogyo Kabusiki-Kaisha Seizou



P120 Toyo w/ Bamboo Cursor



REF Toyo w/ Bamboo Cursor (appeared on eBay)

Toyo w/ Bamboo Cursor- c1940-1945
Made in Japan - Manufacturer Presumed to be Relay
Front Scale: A, [ B, CI, C ] D
Back Scale: [ S, L, T ]
Archive - no longer in collection

Someone in Japan, Prior to, or during WWII provided this with a  bamboo cursor frame. It was given to a young American business woman, now a grand mother, as a gift by a Japanese visitor, prior to WWII. The company name is in the insert. At first I thought this was a one-of-a-kind, possibly a homemade cursor frame, but another showed up as being in Ed Chamberlain's collection, when he put it on eBay (sold for $100). My conclusion is that due to a shortage of steel the company (Toyo) that handed out these slide rules as a promotional item, made these useful with the bamboo frame. This specimens has the 'equivalents' sheet on the back.


Mika (Mickey) Shingo in Aichi, Japan translates the Japanese characters  as:  "Toyo Tokusen-Kogyo Kabusiki-Kaisha Seizou" which means, "Produced by Toyo Specialized Business Development Co., Inc." "Specialized Business Development" implies that this company's business was related to Japanese government (before 1945).



S316 Relay 150
S316 Relay 150 - c1940-1945
Made in Japan - Pre-1945 Relay - missing cursor
Front Scale (extended): 25cm // K, A, [ B, CI, C ] D, L || 10in
Back Scale: [ S, S&T, T ] Equivalents

I found this one that looks like the same company name (see insert) as my P120 above. This tells me that both slide rules must be made by Relay since the Japanese companies were very brand loyal and the distributor would not have used multiple competing suppliers. I assume that this one also had a bamboo framed cursor but it failed to survive the war.


Zodiak Instrument Sales, CA




Zodiak No 150 Duplex Log Log Trig (1955)

ISRM 09.01.12.29
Zodiak No 150 Duplex Log Log Trig dc DK-4
Made in Japan by Relay for Zodiak Instrument Sales,CA.
Front Scale (Trig scales:Deg-Min-Sec)
LL0, LL00, A [ B, K, CI, C ] D, S, ST, T
Back Scale: L, LL1, DF [ CF, CIF, CI, C ] D, LL3, LL2
Donated by David Hecht, Alexandria, VA

Year Codes
First letter in Date Code Example: J.K-1 = 1961

A B C D E F G H I J K L M
1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964
N O P Q R S T U V W X Y Z
1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977

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