MSDOS (can be run in an MSDOS window [click here for MSDOS NOTES] under Windows).

The DYNACOMP ENGINEERING TUTORIALS CDROM is a set of nine complete educational tools designed to teach or refresh engineers and scientists in techniques related to data filtering and transformations. The nine areas covered are: Fast Fourier Transform (FFT); Inverse FFT; Digital Filter Design; the Z-Transform; S-Plane Analysis; Bilinear Transforms; Phase Locked Loops; Frequency Domain Filtering of Images; Waveform and Image Correlation.

Each of the nine modules includes both the software and a complete manual (on CDROM; total manual length over 250 pages) for that unit. Each manual starts with the theory for the unit, and ends with detailed examples. The software is keyed to the manuals, and allows you to experiment with the concepts presented in each associated unit manual.

Detailed descriptions of each unit are available on the DYNACOMP "Catalog-On-A-Disk which may be downloaded from our web site (see below).

Price: $129.95 CDROM with manuals on the CDROM.

Catalog descriptions:

BILINEAR TRANSFORM TUTORIAL

BILINEAR deals with the bilinear transform and how it can be used to derive digital filters from analog RLC filters. The package layout is similiar to the other DYNACOMP engineering tutorials; tutorial documentation with examples, and graphics oriented software.

Price: $39.95

BIQUAD FILTER DESIGN TUTORIAL

BIQUAD FILTERS is another in the DYNACOMP electrical engineering tutorial series, and the product structure is the same: a two-part manual which describes the theory (with many examples) and program operation, and a graphics-oriented software package.

BIQUAD FILTERS not only teaches by example, but also allows the determination of the poles and zeroes required to produce various filters including:

O Analog anti-aliasing.

O Digital low pass, high Pass, and band stop.

You may design Butterworth and Chebyshev low pass/high pass (up to 8 poles) and band pass (up to 4 poles) digital filters, and graphically observe both the analog and digital responses.

To use BIQUAD FILTERS, you must be familiar with the bilinear transform (an earlier tutorial in this series).

Includes a 31-page manual.

Price: $29.95

CORRELATION TUTORIAL

CORRELATION is another member of the DYNACOMP engineering tutorial series. As usual, the package consists of a manual coordinated with software. The manual presents the theory and describes how to use the software, and the software shows visually the principles covered in the manual. The subject areas included are: autocorrelation, power and energy spectra, cross-correlation, cross- spectral density, convolutions, and matched filters.

The computer examples include correlation (e.g., burst correlation, a means for radar ranging) and two-dimensional template matching. Many variations are offered in the examples (e.g., adding various levels of noise to two-dimensional images, random binary signals, random analog signals, different waveforms/templates/pictures).

Graphics are employed wherever possible to make the presentations clear.

Price: $39.95

DIGITAL FILTER DESIGN TUTORIAL

The subjects of transversal, comb and interpolation filters are theoretically discussed (in the manual) with several examples. Windowing (Bartlett, Kaiser, Gauss, raised cosine, etc.) is considered, along with practical approximations to ideal filters.

The software portion of this package is very easy to use and is keyed to the theory in the manual. You may examine the design of filters from several different aspects. For comb and interpolation filters you may graphically look at the amplitude and phase response of a variety of transfer functions under an infinity of coefficient conditions. For transversal filters you can graphically and numerically look at the coefficients associated with many standard types of filters, and truncate/window the resulting series coefficients to examine the practical effect on the filter response. You can even multiple-window. In addition, you can input your own amplitude response coefficients and truncate/window them.

The variety of graphical examples is infinite, making this a valuable tool for instruction.

Price: $39.95

FAST FOURIER TRANSFORM TUTORIAL

FAST FOURIER TRANSFORM TURORIAL is a menu driven, graphics oriented education program designed for both classroom use and self-instruction. The program itself presumes no knowledge of the mathematics associated with Fourier transforms. Rather, it permits hands-on experience showing (in high resolution) what the spectra of various waveforms look like. For example, you may examine the spectra of mixed sinusoidal, rectangular, saw tooth, triangular and random inputs under an infinite variety of conditions. You may even input your own signal. Further, you may examine the spectra of several window functions. The resulting spectra may be plotted as well as listed.

It should be stressed that FFTT is an educational program, which is highly tutorial in character. However, if you want to get a feeling for Fourier Transforms, or already have some knowledge and want to learn more, this is a good program to use. Includes a manual which describes in some detail the mathematics of the FFT.

Price: $29.95

FREOUENCY DOMAIN FILTERING TUTORIAL

FREQUENCY DOMAIN FILTERING TUTORIAL (FDFT) is an extension of FAST FOURIER TRANSFORM TUTORIAL to two dimensions. As usual, the package consists of two parts; the manual and the program disk. The manual describes the theory behind the two-dimensional discrete Fourier Transform along with pictorial illustrations (3-D representations are included). You may then visually examine the results of transforming and filtering various two- dimensional patterns (including bars, sine waves, good old Kirchoff, etc.). The results are displayed as either a spectrum density plot (picture) or a 3-D representation.

You may choose from a menu of ideal filters, or input your own. You may choose images from the menu, or create your own. Instructions are given regarding how to generate your own images. You may also load images from other programs in the DYNACOMP engineering tutorial collection.

Requirements: some initial familiarity with Fourier Transforms.

FDFT is an ideal tool for advanced image students, photographic science students, or scientists interested in reviewing or gaining new, knowledge. Prior experience with FAST FOURIER TRANSFORMTUTORIAL is recommended, but not absolutely necessary.

Price: $39.95

IFFT TUTORIAL

INVERSE FAST FOURIER TRANSFORM TUTORIAL (IFFT) is an educational program which was designed to be used by teachers and students to familiarize themselves with the IFFT and its effect on transforms. It is also useful to engineers and scientists who wish to learn about the IFFT, its operation, and the general ability to reconstruct signals (time functions) from their discrete Fourier transforms.

The documentation is broken into two parts. The first part deals with the theory of the Fourier transform pair in general, the discrete Fourier transform (DFT), the Fast Fourier transform (FFT), and frequency domain filtering. Many graphical examples are included throughout. One of the unique features of IFFT is that it also contains a routine which shows the distortion of serial (e.g., NRZ) transmissions by a telephone line. You specify the length of the line and the baud rate and the IFFT graphically displays the distorted bit pattern. Also shown are the "eye patterns" used by communications engineers to evaluate such transmission lines.

The second part relates to operating the program. To run the program just follow the prompts. You can specify various standard signals (or your own) and the sampling interval. Up to 128 points may be specified (or loaded from disk). Or you can specify the harmonics (up to 64) directly. You may also specify the filter or use a pole/zero description. Real and imaginary coefficients may be used.

You do not need to know how to program to operate IFFT. However, you should be familiar with FFT (see our FFT Tutorial) in general.

Price: $39.95

PHASE-LOCKED LOOP TUTORIAL

The theory part of the package includes discussion of synchronized multivibrators, VCO's the NE555, MC1648, phase detectors, AFC, hold-in range, etc. The program part allows you to experiment with building a phase- locked loop from phase-detector, low-pass filter, and VCO blocks. You may simulate TV synchronization (a picture of Kirchoff may be "played with" and examine hold-in and lock-in both visually and analytically. Of particular interest are the effects caused by the use of various filters and filter functions.

PHASE-LOCKED LOOP TUTORIAL may be used in a college-level electrical engineering course as a teaching aide, or as a refresher.

Price: $49.95

S-PLANE TUTORIAL (SPT)

The SPT manual discusses the development of analog filters through the use of pole/zero representations. Subjects covered include the narrow and broad band approximations, the unit circle, the Butterworth, Chebychev and linear phase solutions.

The second part of the package, the software, allows the determination of complex poles and zeroes and graphical examination of the frequency responses associated with the material in the manual. You may analyze the responses due to the poles/zeroes which you provide, or determine the poles/zeroes and responses for various order Butterworth, Chebychev and Thompson filters. The variety is infinite, and emphasis is placed on graphical displays.

Price: $39.95

Z-TRANSFORM TUTORIAL

In Z-TRANSFORM TUTORIAL poles and zeroes and their relation to the Z-transform are described theoretically (in the manual). The resulting filter response function is discussed with respect to rational polynomials and "tapped delay lines".

The tapped delay line representation is shown to be amenable to a "difference equation" implementation of a digital filter.

The software is keyed to the manual. You may enter either the pole/zero representation, or the rational polynomial

zeroes. If you give the poles and zeroes, the program calculates the transfer function. If you give the transfer function, the program will give you the poles and zeroes. Also, you are provided with plots of the amplitude response and impulse and step function responses.

Several examples are given. If you are interested in learning about the Z-transform, the "unit circle", poles and zeroes, and so on, try Z-TRANSFORM TUTORIAL.

Price: $39.95