ibm 604 ibm 604 electronic calculator at nemo national science museum in amsterdam note plugboard control panel used to program the 604 at bottom the ibm 604 was a control panel programmable electronic calculating punch introduced in 1948 most of the circuitry was based on modifications of circuit designs used in the earlier 603 electronic multiplier and was packaged in small onetubereplaceable pluggable units which made the product more easily manufactured and serviced clock speed was increased from the 603s rate of 35khz to 50khz the 604 performed fixed point addition subtraction multiplication and division using bcd arithmetic initial versions supported 40 program steps and this was soon expanded to 60 processing was still locked to the readerpunch cycle time thus program execution had to complete within the time between a punched card leaving the read station and entering the punch station the 604 and a modified version the 605 were used as components of the card programmed electronic calculators cpc and cpc ii the 604 was also a component of the test assembly a precursor to ibms early computers the circuit module design and packaging was also used for the ibm 650 a popular early computer an alltransistor version of the 604 was built and demonstrated in october 1954 although it used about 2000 transistors an ibm 604 is preserved at the american computer museum and another at the university of amsterdam computer museum photos ibm 604 vacuum tube modules single vacuum tube module twotube modules list of ibm products list of vacuum tube computers ibm 604 electronic calculating punch notes manuals ibm 1954 ibm 604 electronic calculating punch manual of operation ibm form 22527910 pdf ibm 1958 ibm customer engineering manual of instruction 604 electronic calculating punch ibm form 22776090 pdf university of amsterdam computer museum ibm 604 columbia university acis history ibm 604 