Hewlett-Packard HP-65

Date of introduction:  January 19, 1974 Display technology:  LED
New price:  $795 Display size:  10 + 2 
Size:  6.0" x 3.1" x 1.5"    
Weight:  11.0 ounces Serial No:  1333A14611
Batteries:  3*NiCd AA-size Date of manufacture:  wk 33 year 1973
AC-Adapter:  HP-82002 Origin of manufacture:  USA
Precision:  10 Integrated circuits:  HP65-CPU, Mostek MK6111...MK6113
Memories:  9    
Program steps:  100 Courtesy of:  Peter Muckermann

Hewlett-Packard introduced in January 19, 1974 with the HP-65 the first truly handheld programmable calculator. In a housing slightly larger than the HP-35 a card reader for tiny magnetic strips was accomodated. Users could store programs up to 100 steps lenght on the cards or buy pre-programmed cards from both Hewlett Packard or third party companies. The HP-65 was replaced after 2 years with the HP-67 featuring 224 merged program steps and 26 memories instead of 100 partially merged steps and 9 memories. Compare the specifications with the Texas Instruments SR-56 and SR-52.

The HP-65 uses the Reverse Polish Notation with the ENTER key instead the usual = key.

The internal view of the HP-65 gives a very solid construction. HP-65_1.jpg (116681 Byte)
The main printed circuit board with the huge CPU and three ROM's (Read Only Memories). HP-65_PCB.jpg (118730 Byte)

Learn more about Mostek Calculator Integrated Circuits.

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Joerg Woerner, May 3, 2002. No reprints without written permission.