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The track density and linear recording density trend in high performance digital tape recording systems has recently made a move to a point that conventional ferrite based recording heads cannot support. The move has been from the 18 and 36 track fixed head technology to 128, 256 tracks and up that require high coercivity tape (1600-2000 Oe), track following servos, high moment pole recording heads and narrow track MR read elements. This paper will outline the progression and discuss the impact of the above requirements on the design of multi-track tape heads. Although track widths in even the most recent tape systems are still relatively large compared to the leading edge disk heads, the multi-element arrays required dictate more stringent process control and correspondingly more lenient designs in order to obtain any usable yield. As will be shown, the record heads for recent tape systems are remarkably similar to thin film disk head designs which are used in on a slider. In multi-track tape head thin film layouts, a device yield of 9 0 9 can quite easily deliver zero multi-track tape heads, whereas such a yield in the disk arena would be most satisfactory. The similarity of the new tape device designs to the thin film disk head is limited by the recording, tribological and mechanical attributes of the media. The recording performance has to consider the media thickness where recording codes with wide ranging densities, such as (l,7), will likely saturate MR read heads at lower densities and be hard to overwrite. One solution for this is the use of write equalization which successfully reduces the flux swing at low densities but imposes the need for high frequency pulses delivered to the write head for recording very high density signals. The tape environment also drives more stringent tribology and environmental reliability issues due to direct media contact and nonsealed tape drives exposed to atmospheric contaminants. It is also to be noted that the use of flexible media in an uncontrolled environment using a two gapped read-while-write tape head, drives the read element width to significantly lower values than the write width or track pitch to gain adequate TMR allowance for reliable performance. If this trend continues this latter point implies that the read width will be driven to much narrower dimensions than for disk applications for an equivalent areal density. This may put GMR based read heads earlier on the areal density trend line than expected from data based on disk systems. 9:36 AA-02. RECORDING CHANNELS FOR HIGH DENSITY TAPE SYSTEMS. N. Koren (Eastman Kodak Co., 3985 Sorrento Valley Blvd. San Diego, CA 92121) and R. C. Schneider* (Storage Technol. Corp., MS-4274, 2270 South 88th St., Louisville, CO 80028)In the forty years from 1953 to 1993, the number of tracks in high-end half-inch linear tape drives increased from seven to thirty-six, a factor of only five. In the 1990's however, the number of data tracks on the same half-inch width jumped to over a hundred. Today, systems with over five hund...