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Articles

FryPro2: FryKleaner Professional, Part II (807k pdf)
Unpublished 02/07 - Construction article on how to build your own industrial cable break-in machine.

How to Solder Surface Mount Devices (4.16M wmv)
Unpublished 01/07 - Video showing a technique for soldering fine pitch chips.

Clarion: A Simple 2A3 Design Project (1832k pdf)
Unpublished 11/06 - Construction article describing the design and assembly of the Clarion 2A3 amplifier.

Rip Your Vinyl to Bits With a USB Phonostage (907k pdf)
Unpublished 11/06 - Brief description of The Ripper digital phonostage and it's operation.

Why Not 16-bit No-OS No-Filter Conversion? (186k pdf)
Unpublished 09/05 - Explanation of why I chose to use 8x oversampling, 24-bit interpolation, and output filtering in the HagDac design.

The Serious Audiophile (1.62M wmv)
Unpublished 07/05 - Video skit showing Hagtech tube products.

Conditioner: An Audiophile Line Filter (1165k pdf)
Unpublished 08/04 - Assembly instructions for building an AC mains line filter to match the Clarinet and Cornet preamplifiers.

Monogram: a Tube Phonostage for 78s (742k pdf)
Unpublished 04/04 - Assembly instructions for building a mono phono and linestage with variable equalization. Based on the Cornet Classic circuit board.

FryKleaner: an Audio Burn-in Generator (363k pdf)
audioXpress 03/04 - Technical description of unique burn-in waveform and circuit design.

CCD Camera for Amateur Astronomy (20k pdf)
Unpublished 07/99 - Contest submission describing how to build a low cost CCD camera using a Zilog Z80 processor with built-in USB controller. Shows how to apply the processor's I/O for analog purposes.

UltraGraph Optics Design (557k pdf)
Unpublished 05/99 - Design study describing my low cost portable ultraspectral camera concept.

Underwater Camera Mapping System (47k pdf)
Unpublished - 04/99 - MathCad calculations of the imaging response for a false-color seafloor mapping camera. This was actually built and operated. I wrote the real-time imaging software and designed the electronics and control systems.

On Reference RIAA Networks (47k pdf)
Audio Electronics 03/99 - Proposes an improved transfer function relative to traditional networks. Presents reference values from calculations and simulations.

SNR Calculation for UAVHIS (172k pdf)
Unpublished 02/99 - Mathematical study of electro-optic capabilities for an airborne hyperspectral camera.

Calculating Optimum Snubbers (1304k pdf)
Audio Electronics 01/98 - Analyzes causes of interference due to rectifier switching noise on ac-dc power supply inputs. Proposes a low cost solution without resorting to exotic diodes. Uses SPICE simulations to demonstrate theory.

Stabilization and Scanner Requirements (1170k pdf)
Unpublished 06/97 - White paper analyzing the requirements and specifications for two airborne imaging systems. I actually designed and built the second one (laser fluorescence imager).

Single Lens Color ILA Projector (74k pdf)
Asia Display 1995 - Invited paper describes the Hughes-JVC Technology Model 200 ILA projector.

Modified T-Coil Network (21k pdf)
Unpublished 09/95 - Brief presents the equation for calculating a series resistor which when added to a T-coil network reduces the magnetic coupling to zero (M = 0). Simple inductors can then be used rather than a difficult to construct transformer.

Calculating RC Snubbers for Yoke Damping (33k pdf)
Unpublished 09/95 - Applies RC snubber technique to CRT yoke and other coil damping. Describes method for a simple and accurate coil self-resonance measurement.

A Look at Video Amplifier Peaking Networks (953k pdf)
Unpublished 03/95 - Discusses different video amplifier peaking topologies and presents a new improvement on the bridged T-coil network.

Optimum Spot Size for Raster-Scanned Monochrome CRT Displays (400k pdf)
Journal of the SID 1993 - Derives the optimum CRT spot size by using raster parameters.

Some Notes on Aperture Correction (724k pdf)
Unpublished 04/93 - Mathematical analysis of sharpness control in analog CRT displays. Study looks at effect of variables on image performance.

SPICE Model Formulas (403k pdf)
Unpublished 11/91 - Equations for building useful component models based solely on typical data sheet information. Take with a grain of salt, but can result in superb transistor models.

Video Risetime Requirements for Computer-Driven Raster-Scan CRT Displays (412k pdf)
SID 1990 Digest - Analyzes the effects of spot size modulation and video amplifier risetime on the horizontal resolution of a CRT display. Proves that MTFA and SQRI theories are incorrect because they assume a linear model. Uses a custom convolution program to simulate the nonlinear system.

Video Amplifier Performance Criteria for High Resolution Displays (944k pdf)
Unpublished 03/88 - Analyzes effect of bandwidth limitation on displayed resolution. Derives criteria for minimum step error and minimum required bandwidth.