Tape Reel Research Articles

Making the Invisible Audible: A Simple Sound-Emitting Water Level Meter.

Making the Invisible Audible: A Simple Sound-Emitting Water Level Meter.

A Reassessment of Wolfgang Sichardt’s 1936 Field Recordings of Swiss Yodel

Historical field recordings offer insight both into past performance routines and into the processes and contexts of musical practices in their time. In the wake of renewed interest in musical traditions of the alpine region, I reassessed the magnetic tape recordings created by the Jena University doctoral student Wolfgang Sichardt (1911–2002) from multiple perspectives. The premises and context of the field research in 1936 are reconstructed, in part based on original correspondence; the reception and impact of the research in Germany and Switzerland are assessed; and the exact origin of the recordings is determined wherever possible. Descriptive transcriptions of the entire corpus of yodel and alphorn music visualize the content. The 1936 field recordings, made by Sichardt during a six-week field trip to different areas of Switzerland, document yodels, folk songs, and alphorn melodies on 12 magnetic tape reels, recorded with the latest technology at the time, the AEG Magnetophon K-2. Although the results were published afterward (Sichardt, 1939), the magnetic tape recordings remained private until they were donated to the Vienna Phonogram Archive in 2008, and only in the past decade have they been discovered by researchers.

Some Assembly Required: Low-Cost Digitization of Materials from Magnetic Tape Formats for Preservation and Access

Recent work discussing the digitization and preservation of magnetic tape materials has maintained that it should be left to expert practitioners and that the resulting digital materials should be stored in digital repositories. This article suggests that librarians and archivists lacking extensive technical skills or access to expertise can digitize these materials themselves. It provides a detailed account, including challenges faced, of how a team of practitioners without prior training or experience digitized historical audio recordings on cassette and open reel tape at Northern Illinois University Libraries. The discussion reviews the assembly of equipment and software that the team used for digitization work, discussing each element’s significance and how they came together as a functioning workflow. The authors also emphasize the fact that while the digitization of fragile and/or degraded magnetic tape materials may contribute to the preservation of their contents, this action also creates a new set of materials with their own preservation needs. Realizing that many practitioners serving medium-sized and smaller institutions lacking large financial resources may not have access to a full-fledged digital repository, they suggest the use of the National Digital Stewardship Alliance’s Levels of Digital Preservation rubric as a means by which practitioners may incrementally increase the probability that digital materials made from magnetic tapes will remain accessible.

Low RH and temperature effect on 0201 sized passive components during SMT mounting

PurposeLow relative humidity (RH) effect surface mount devices in numerous ways. The smaller size (0201) capacitor and resistor start wasting when RH is low. Due to low RH, electrostatic charges built-up on the surface of surface mount devices (SMDs) and component’s reel. The positive charged SMDs stick with the negatively charged reel tape and are wasted. This paper comprehensively explores the environmental effects on 0201 size surface mount devices during mounting process. Different type and size of surface mount devices are tested in low and desired RH to validate the effectiveness of the proposed approach. This paper will also highlight high electrostatic discharge (ESD) due to low RH which can be detrimental for small size surface mount devices. The experimental and graphical illustrations will stipulate the results of success rate for mounting components. The effect on ESD, subsequently varying temperature and humidity will also be analyzed.Design/methodology/approachIn this paper, 0201 SDMs will be considered for analysis. The surface mount technology (SMT) plant temperature and humidity has been varied to examine the properties of small size SMDs. Total 5 hours production data are collected from Laptop motherboard production environment. This approach is applicable to all SMT environment.FindingsThe authors reduced the wastage of 0201 chip size resistor and capacitor. Total 11 components are selected of this size, and there success rate is observed during mounting. These components are first observed in harsh environment where the temperature is first set to 20ºC and RH is set to 25 per cent. The success rate of these components is very low due to component’s wastage. When the plant temperature is set to 25ºC and RH is set to 45 per cent, the success rate of mounting increased up to 100 per cent. A single component placement success rate with respect to RH is observed for one month. The results are shown in Table IV. It can be seen that the success rate is near 100 per cent when RH and temperature is maintained in production environment. To eliminate the ESD build-up in material and equipment in manufacturing environment humidification is a very effective way. When the RH is kept to 45 per cent, the moisture content of the air is a natural conductor and earths any ESD in environment.Originality/valueExperimental data have been obtained from Laptop motherboard manufacturing process to validate the effectiveness of proposed approach.

Watching harmonics beat

Suppose you record a song on magnetic tape and duplicate your recording. You then simultaneously play back both tapes. To the rim of one of the tape reels, also known as the reel's flange, you keep applying gentle pressure and then releasing that pressure so that your reel alternates between slightly lagging the other and then catching up with it. The resulting small pitch differences between the two tapes give rise to an intriguing and pleasant sound often described as swirling or jet-like. A Wikipedia article1 lists dozens of popular songs that incorporate this “flanging” effect. Well represented are songs by the Beatles and Jimi Hendrix as well as by artists from recent decades. But perhaps the most important is an obscure 1945 recording by guitarist and musical inventor Les Paul, who is recognized as the discoverer of flanging.

Unidentified Sounds: Radio Reporting From Copenhagen 1931–1949

This article investigates how urban spaces and their noises were approached by radio reporters in the first decades of public radio production in Denmark. Focusing on the period before reel tape was incorporated in production by the early 1950s, the author explores how urban space and urban sounds were heard, contextualized, and conceptualized in an era of transmission. Observing that urban sounds until the late 1930s were rarely heard in Danish radio compared to German and English broadcasting, the author argues that an urban and auditory aesthetics incorporating noise, heterogeneity, and unpredictability did not really develop in Danish radio until the early post-war years. Yet this study traces early attempts at managing noisy urban conditions in a collection of 22 archived reportages from 1931–1949 and demonstrates how reporters experimented with available technological repositories and developed techniques in order to make sense in and through urban environments. Inspired by Michel Serres' idea of the parasite, the author analyzes such techniques as ways of distinguishing between noise and meaningful sounds, and ultimately identifies three different types of urban sonic environments in the period: the extraordinary, the everyday, and the socially foreign.

Tape transport control based on sensor fusion

Reliable and precise tape transport is of fundamental importance to achieve larger volumetric recording densities in tape storage systems. The performance of the tape transport control system, which is affected by variations in the tape velocity and tension, impacts the write and read quality of the data tracks and eventually the achievable areal recording density. During operation in cruise velocity mode, disturbances in velocity and tension may be induced for example by tape reel eccentricities. This problem is particularly serious when the reel rotation frequencies are close to the resonance frequency determined by the tape path. Typically, the tape velocity is estimated at the tape head from a servo signal, which is obtained by reading pre-formatted servo information, and used for tape transport control during cruise mode. In such a scheme, velocity disturbances observed at the head cannot be attributed to an individual reel. Hence no targeted disturbance suppression can take place at the individual tape reels. However, Hall sensors are typically included in tape drives to obtain additional tape velocity information from the individual reels. This information is used to achieve proper tape transport operation in the absence of valid velocity estimates from the pre-formatted servo information, for example during tape acceleration. In this paper, we present a novel control scheme for tape transport that uses velocity measurements from three sources, the Hall sensors at the tape reels and the servo channel that yields velocity estimates at the head. Specifically, characterization of the multiple-input multiple-output (MIMO) tape transport system provides an accurate system model and enables an optimized two-sensor control design. Furthermore, H∞ filtering is employed to perform sensor fusion and the resulting state estimates are used in the feedback control of the two reels. Experimental results are presented to illustrate the behavior and performance of the proposed tape transport control system.

Coupling between the in-plane and lateral tape dynamics in high capacity linear tape transport systems

Lateral tape motion (LTM) is defined as the lateral deviation of the tape from its prescribed strain-free state path. The effects of tape, roller, guide or reel imperfections on the LTM are reasonably well understood. Yet, the effects of disturbances in the longitudinal (in-plane) direction, which can couple into LTM, have not been well described. Longitudinal tape vibrations can be due to, but not limited to a) tension dynamics due to servo control of the tape reels, and/or tension impulses due to the unwinding of tape layers that experience sticking. The problem is further complicated due to the uncertainty of the tape length on the downstream side, as a result of the “floating layers” in the take-up reel. In this work, the equations of motion of the longitudinal and lateral tape motion are derived from first principles. The coupling due to non-linear longitudinal strain is considered. The equations of motion are solved by using the finite element method, and an explicit time integration algorithm. The entire tape path is modeled directly, where the interaction of the tape with the recording head and the guides are represented as concentrated forces, and moments. The effects of disturbances, typical for a tape transport system, on the coupling or lack there off are investigated.

Adaptive Regulation of Time Varying Disturbances in a Tape Storage System

Archival demands for digital tape storage systems require smaller spacing between data tracks on the magnetic tape to allow for more data storage on a single cartridge. Increasing track density while maintaining track following provides a challenge for the servo control of the tape drive. In particular, interchangeable tape cartridges and time-varying tape reel diameters during operation cause variable disturbances during servo control. In this paper we show how a tape servo control algorithm can be regulated to handle changes in disturbance dynamics during servo operation of the tape drive. The approach is based on adaptive regulation by exploiting a Youla-Kucera parameterization of the servo controller and an explicit minimization of the Position Error Signal (PES) during servo operation in real-time. Theoretical results on the stability of the feedback system and real-time application results on an Linear Tape-Open (LTO) drive are included in the paper. The result show a significant reduction of the variance of the PES over different tape cartridges and a constant PES variance during a complete reel-in operation of the tape drive.

Hula hula!

The best way to explain the shape of a hoop is by letting the children experiment, handle and play with a range of objects that are hoop-shaped. Try asking them to think of all the objects they can that are shaped like a ring or hoop, or to find some at home and bring them into the setting to show and share. Why not try using the rings and bangles we wear as jewellery, for example? Polo mint sweets, ring doughnuts, rubber bands, reels of sticky tape, hair ‘scrunchies’, car or bicycle tyres, the washers from a toolbox, and certain brands of crisp-like snacks and breakfast cereals, could also be used.

Deposition of diffraction images to be discussed at the Open Meeting of the Commission on Biological Macromolecules of the IUCr in Osaka

Deposition of diffraction images to be discussed at the Open Meeting of the Commission on Biological Macromolecules of the IUCr in Osaka

A Machine Vision System for Inspecting Tape-Feeder Operation

A tape feeder of a SMD(Surface Mount Device) mounter is a device that sequentially feeds electronic components on a tape reel to the pick-up system of the mounter. As components are getting much smaller, feeding accuracy of a feeder becomes one of the most important factors for successful component pick-up. Therefore, it is critical to keep the feeding accuracy to a specified level in the assembly and production of tape feeders. This paper describes a tape feeder inspection system that was developed to automatically measure and to inspect feeding accuracy using machine vision. It consists of a feeder base, an image acquisition system, and a personal computer. The image acquisition system is composed of CCD cameras with lens, LED illumination systems, and a frame grabber inside the PC. This system loads up to six feeders at a time and inspects them automatically and sequentially. The inspection software was implemented using Visual C++ on Windows with easily usable GUI. Using this system, we can automatically measure and inspect the quality of all feeders in production process by analyzing the measurement results statistically.

Innovations in tape storage automation at IBM

In the mid-1980s, tape storage appeared to be heading toward the graveyard. Storing information on large reels of tape that had to be manually mounted was expensive, inefficient, and prone to human error. In addition, competition from hard disk drives (HDDs) was growing. Data access on HDD was faster because the data was stored in a manner for rapid random access, not linearly as on tape, and HDD capacity was rapidly growing. Then, in 1984, IBM introduced the half-inch tape cartridge (3480), which was novel in its small form factor. In 1986, an automatic loading mechanism followed. In 1987 and 1988, competitors introduced the first automated tape libraries to use the half-inch tape cartridge. Suddenly, tape storage became considerably easier to use and more efficient. With automation, it also represented the least expensive way to store data. In 1993, IBM introduced the 3495 tape library, and now offers several different automated libraries ranging from the smaller 3575 MP and 3581/3583 models to very large libraries such as the 3494 and 3584 models. This paper examines the history of IBM tape storage and automation products, including the engineering challenges that were met in response to users' pressing requirements; it also examines the future of automated tape storage.

Measurement and origin of tape edge damage in a linear tape drive

Integrity of the magnetic tape edge is the key to maintaining high performance of modern tape drives. Damage to the tape edge under normal drive operation results in the change in tape dimensions and debris generation, both leading to degradation in the reproduction of the recorded signal. The objective of the present study is to develop a methodology for evaluation of tape edge quality and to apply the methodology to monitor tape edge degradation under normal drive operation. Optical microscopy, atomic force microscopy and scanning electron microscopy are employed to study and quantify the quality of the tape edge. AFM measure-ments were made on both individual tape layers and the tape reel. An edge quality measurement technique is used to quantify the damage to tape edge. A technique for the tape lateral motion measurement is used to study the effect of continuous sliding on tape guiding. A lateral force measurement technique is developed to measure the force exerted by the tape edge on the guide flange. The effect of normal drive operation on tape edge quality and on tape guiding in a linear tape drive is studied. It is shown that two edges of a factory-slit tape are imperfect and different, with cracking of the magnetic coating occurring at one edge. Under normal drive operation, one edge experiences more wear with larger amount of debris produced. This larger debris generation occurs on the edge with cracks developed during manufacturing. A possible mechanism of tape edge wear under normal drive operation is proposed.

테이프 피더의 부품공급 정밀도 측정을 위한 검사 시스템

A tape feeder of a SMD(Surface Mount Device) mounter is a device that sequentially feeds electronic components on a tape reel to the pick-up system of the mounter. As components are getting much smaller, feeding accuracy of a feeder becomes one of the most important factors for successful component pick-up. Therefore, it is critical to keep the feeding accuracy to a specified level in the assembly and production of tape feeders. This paper describes a tape feeder inspection system that was developed to automatically measure and inspect feeding accuracy using machine vision. It consists of a feeder base, an image acquisition system, and a personal computer. The image acquisition system is composed of CCD cameras with lens, LED illumination systems, and a frame grabber inside the PC. This system loads up to six feeders at a time and inspects them automatically and sequentially. The inspection software was implemented using Visual C++on Windows NT with easily usable GUI. Using this system, we can automatically measure and inspect the quality of all feeders in production process by analyzing the measurement results statistically.

Long‐term mechanical and viscoelastic behavior of constitutive polymeric materials used for magnetic tapes

AbstractCreep‐compliance behavior of specially prepared magnetic tape materials was measured at elevated temperature levels to facilitate the use of a time–temperature superposition (TTS) process. This TTS process allowed for the construction of master curves at a reference temperature of 30°C, which were used to predict the long‐term viscoelastic behavior of the magnetic particle (MP) and metal‐evaporated (ME) tapes used in the study. The specially prepared samples allowed for the use of a rule of mixtures technique to determine the long‐term creep compliance of the front coat and back coat used for the magnetic tapes. To test the validity of this procedure, the front coat, substrate, and back coat data determined through separate experiments were used to calculate creep compliances of simulated tapes. These calculated creep‐compliance curves were then compared to measured data for the actual magnetic tapes. After determination and validation of the front coat, substrate, and back coat creep‐compliance data sets, they were used to determine strain distributions when the tapes are stored in a reel. Strain distributions were calculated for two cases, which reflect how tapes are stored in different drives: (1) the front coat (magnetic + nonmagnetic layer) is oriented away from the hub, and (2) the front coat is oriented toward the hub. Results showed that strain in the critical front coat of a tape is lower if it is stored with the front coat oriented toward the hub. In addition, the use of the creep‐compliance data showed that the MP tape front coat is more susceptible to creep than the ME tape front coat. The strain distributions in future magnetic tapes were also simulated by reducing the thickness and compliance of the layers. Results showed the importance of using lower compliance front coat, substrate, and back coat materials if thinner tapes are to be developed to increase the volume of information that can be stored in a magnetic tape reel. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1142–1160, 2001

Cryptographic redundancy and mixing functions

This paper studies the use of structures based on error correcting codes to achieve secrecy rather than error control. In many cases, however, the same code can achieve both error control and secrecy. It describes an optimal construction for combining multiple semisecure channels, e.g., a bundle of fiber-optic cables or reels of tape sent by independent couriers, into a single channel with much higher security. It shows how mixing and scrambling functions formed from error correcting codes can be used to enhance the security of trunked communications circuits and conventional cryptographic systems which depend, for their security, on unproven assertions about computational difficulty.

5468901 Process for the preparation of optically active methionine amide

Lateral tape motion (LTM) is defined as the lateral deviation of the tape from its prescribed strain-free state path. The effects of tape, roller, guide or reel imperfections on the LTM are reasonably well understood. Yet, the effects of disturbances in the longitudinal (in-plane) direction, which can couple into LTM, have not been well described. Longitudinal tape vibrations can be due to, but not limited to a) tension dynamics due to servo control of the tape reels, and/or tension impulses due to the unwinding of tape layers that experience sticking. The problem is further complicated due to the uncertainty of the tape length on the downstream side, as a result of the “floating layers” in the take-up reel. In this work, the equations of motion of the longitudinal and lateral tape motion are derived from first principles. The coupling due to non-linear longitudinal strain is considered. The equations of motion are solved by using the finite element method, and an explicit time integration algorithm. The entire tape path is modeled directly, where the interaction of the tape with the recording head and the guides are represented as concentrated forces, and moments. The effects of disturbances, typical for a tape transport system, on the coupling or lack there off are investigated.

針状コバルトフェライト磁気テープの電磁変換特性

Two kinds of acicular cobalt ferrite fine particles which differed in size (long axis : about 1.2μm and 0.4μm) were prepared by conventional sintering method. Then two kinds of acicular cobalt ferrite tapes were fabricated with these fine particles and binder regins. The recording characteristics of these tapes were measured by using commercially available open reel tape deck. The output of the magnetic tape made of acicular particles, of the order of 1.2μm decreased linearly in the high density recording region because of a spacing loss. The output of the magnetic tape made of the acicular particles, of the order of 0.4μm increased in the high density recording region.This was because the fine particles were densely packed in the medium and the roughness of the surface of the tape was smoothed by improving the dispersive quality.

Measurement of head wear rates using custom high sensitivity electrical elements

A technique for measuring the wear rate of a tape recording head is described that can produce a theoretical dimensional resolution of 0.02 nm. Custom four wire elements are located in the gap of the actual recording head design to be tested (rather than using substitutes) and can be strategically placed to measure the wear rate across the width of the tape. Temperature compensation is achieved by measurement of a spare identical element in the head structure set back from the wear surface such that it does not receive wear. The wear rate at various locations across the head gap lines of NiZn ferrite heads have thus been obtained continuously as a function of the amount of CrO/sub 2/ tape passed and show that the wear rate is greater near the tape edges. Due to the high sensitivity of the test elements, use of long reels of tape and placement of multiple heads in the same tape path, comparisons of head contour shape and/or materials can be made in a very short test time.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>