[IBM 2420 MAGNETIC TAPE UNIT]

[Music] before the show begins adjust your sound and focus my voice should be easily heard in all parts of the room beep and Flash should synchronize if they do not recheck the threading directions on your projector [Music] from one of IBM's newest engineering and Manufacturing facilities located in Boulder Colorado come as an ADV aned development in tape drive technology the IBM 2420 Magnetic Tape unit before demonstrating the loading time of the 2420 let's first clock the loading time of the 2400 series model 6 now let's compare the 2400 loading time with that of the [Music] 2420 the IBM 2420 Magnetic Tape unit provides an increased tape speed faster access time rewind characteristics far superior to existing IBM tape drives thus substantially improving the throughput of system 360 early in 1965 a program was started to develop a superior tape drive which would achieve improved reliability and performance while staying compatible with the 2400 line the resulting IBM 2420 offers the following characteristics tape speed 200 in per second recording 1600 bits per inch phase encoding data rate 320 KB access time 2 milliseconds rewind in columns at 500 in per second in addition threading is automatic and the 2420 also provides cartridge loading now let's examine each of these features more closely automatic threading is accomplished by mounting the reel on the machine Hub and making sure that the end of the tape lies on this Chute now all the operator needs to do is push the load rewind button the tape is loaded immediately in unloading the tape rewinds completely on the supply reel let's observe each step of the automatic threading operation here a mini reel is being loaded any IBM standard halfin wide tape reel can be used the cycle starts as the Reel rotates once the tape end reaches the first threading block air Jets move the tape forward from the read right area the tape moves in the channel until it reaches the second threading channel the vacuum creates created behind the Jets keeps the tape from falling into the column once the tape passes the second threading Channel it moves to the takeup Reel which has a vacuum Hub while it is recommended that the tape end be free of folds creases and dirt for best threading reliability it is possible to load successfully with crumpled ends a wraparound type cartridge also has been developed for use with any 10 1/2 in solid flange reel this cartridge can be taken directly from Storage to the drive thus completely eliminating the operator's handling of the tape when installing the cartridge the operator lines up this key with the mating slot on the drive after installation the cartridge is automatically opened then air pressure is supplied through the hole from the drive air pressure blows through air jets in the inner surface of the cartridge to flutter the tape and direct it through the cartridge opening the use of air pressure in the cartridge makes it possible to handle leaderless tape automatic threading is simplified by the use of straight line loading the tape floats on these air bearings by inverting the tape path the oxide is on top with the result that the only tape path components on the oxide side are the head and the cleaner increased reliability results from the use of this single capston which drives the tape on the non-recording side and controls tape Motion in all modes of operation the capston is mounted directly on the motor which is simple in construction and has a high torque to inertia ratio the these two tapered columns help achieve faster access Time by decoupling the tape the characteristics of the motor and the decoupling columns make the 2 millisecond access time possible let's compare the start characteristics of both the 2420 and 2400 model 6 the 2420 starts moving tape immediately in the 2400 model 6 1 and 1 12 milliseconds are required to start tape motion now let's look at rewind characteristics maximum rewind time for 2400 ft of tape is 1 minute for both the 2400 and the 2420 2420 in column rewind speed is 500 in per second the 2400 on the other hand rewinds at low speed if less than 600 ft is to be rewound the 2420 uses solid Logic Technology throughout and the number of mechanisms and components have been greatly reduced the result fewer and easier adjustments the 2420 features increased design Simplicity tape motion is performed by the single capston motor and two reel Motors that are directly coupled to the tape reel and perform the functions of load normal operation high-speed rewind and unload all these design features mean improved performance increased reliability the 2420 is fully compatible with the 2400 phase encoded drives with both utilizing the same control unit the IBM 2420 Magnetic Tape unit featuring increased tape speed faster access time Superior in column re rewind characteristics automatic threading cartridge loading simplified construction fewer Parts improved reliability all resulting in faster throughput and Superior data handling character iscs [Applause] [Music]