"Measurement of Telemetry System Errors," (co-authored with Lyle H. Taylor)
Proceesings of National Telemetering Conference, 1961. We devised
a technique to measure the system errors using shaped white noise and
periodic wave inputs. This method has several advantages including
determining which system components make the largest contribution to the
system error. Download the pdf file by clicking
"A Study of the Stationarity of Laboratory Random Noise Generators,"
IEEE Transactions on Instrumentation and Measurement, Vol IM-15,
1966. This covers the details of an experiment to determine the output
stationarity of several commercial noise generators. The noise output
needs to be reasonably stationary for measurement results to be
repeatable. Download the pdf file by clicking
"Introduction to Digital Spectrum Analysis," MSEE thesis, New Mexico State
University, September 1969. This paper logically develops the concept of
power spectrum analysis by digital computer. Beginning with the so-called
indirect method of autocorrelation and Fourier transformation, ideas such
as statistical reliability of spectral estimates and the use of inner
spectral windows are covered. Section 3 treats symmetrical convolution
filters by first developing several low-pass filters and discussing such
characteristics as their noise bandwidth and truncation errors. Band-pass
filters are then derived from the low-pass prototypes. Then in Section 4,
the uses and misuses of the Schuster periodogram are described. Known
spectra are generated and then analyzed by the various filter types.
Click here to download
a pdf copy. 202 pages, 16.7MB.
"Over/Under Voltage Protector", Electronics Now, Sep
1995. This article is on the "original" protector circuit
which uses a manual Reset switch. Later versions use an automatic
reset after 90 seconds. Information on these later versions will be
sent on request. Click to download
a pdf copy of the origianl article.
"Photographs: Darkroom or Electronic?", Midnight
Engineering, Nov/Dec 1995. (Compares film and
"SNAPPY" B&W photos for data sheets and ads.)
"SNAPPY for Color Photos", Midnight Engineering,
"The DC Volt", Nuts & Volts, Jan 1997.
I don't have a printed copy of the published article but I'm posting
a copy of the article as a zipped pdf file with the Figure 4 photo
as a color jpg file. Click here to download it.
"Find NIST Data On- and Off-Line", Test & Measurement
World, Jan 1997.
"Circuit tests power outage susceptibility", EDN,
Mar 3, 1997 (Design Idea).
"The AC Volt", Nuts & Volts, Apr 1997. Click here
to download ACVOLT.PDF , Size: 877 kB.
"Add an RS-232 Output to any PIC Microprocessor",
Electronic Design, May 12, 1997 (Idea for Design).
Selected "Best of The Issue" by reader
votes! This article in ASCII text only may be downloaded by
clicking on RS232.ZIP Size: 3.8 KB.
"Breadboards - Then and Now", Nuts & Volts,
Oct 1997. (Breadboard your ideas faster and with less frustration with
this updated 20 year old design.) Download the breadboard artwork in
Gerber format by clicking on GERBERS.ZIP
Size: 68 KB.
"All About Attenuators", Electronics Now, Sep 1998.
Download the article as a 600 dpi Adobe pdf file by clicking
here . (attenuat.zip, size about 4.8 MB)
Download the PIC software for the LM1972 active attenuator and the
design equations for the resistor values in Figure 1 by clicking on
ATTEN.ZIP Size: 5.4 KB.
"New Life for a Vintage Audio Filter",Nuts &
Volts, July 1999.
"An Improved AC/DC Voltage Reference",Nuts &
Volts, Jan 2000. Download the PC board artwork, panel drilling
drawings and artwork by clicking on MODEL305.ZIP
Size: 39KB. (The voltage reference comparison table was omitted
from the published article so I've added it and the circuit board
Gerber files to MODEL305.ZIP on 02/25/00.)
I have some new (Feb 00) information on finding used Kelvin-Varley
voltage dividers in KEL-VAR.ZIP
(zipped .pdf and .jpg files). Size: 76KB.
An IC voltage reference comparison was published in the Nov 99 issue
of Texas Instruments Analog Applications Journal. You can
download the "zipped" pdf file
"All About Correlation", Circuit Cellar, April 2000.
Download the article as a 600 dpi pdf file by clicking
here. Size is about 1.5 MB.
Download the software mentioned in the article:
CORRELAT.ZIP Size: 114 KB.
"Temperature Measurement and Control",Nuts & Volts,
April 2000. Download the additional info file:
TM&C.ZIP Size: 1.4 MB.
"Another AC-DC Voltage Reference", Nuts & Volts , June 2000.
Download the PC board artwork, panel drilling drawings, software, etc.
by clicking on BUILD306.ZIP, Size: 74kB.
(Last updated 06/22/00.)
You can also download the latest hardware and software information
by clicking on USER306.ZIP and
"All About Electronically-Tunable Active Filters", Poptronics,
August 2000. Download the PC board artwork, PIC software and SPICE
models mentioned in the article by clicking on
TUNABLE.ZIP, Size: 19kB. Download the full article as a 600 dpi
Adobe pdf file by clicking here. Size
is about 2.75 MB.
"Build this Simple, High-resolution DC Voltmeter", QEX (ARRL
Technical Journal), Sep/Oct 2001. Circuit board is available from FAR
Circuits, phone 847-836-9148 or online at www.cl.ais.net/farcir/
Download the full text as a 600 dpi Adobe pdf file by clicking
here. (hires-vm.pdf, size about 2 MB.)
Download the MS-DOS control program by clicking on
CNTRL251.ZIP, 19 kB. Download the LTC2400 demo program written
by Linear Technology Corp. by clicking on
2400.ZIP, 2.5 MB. (This is a Windows program that will also control
this voltmeter.) Download the circuit board drawings by clicking on
svmeter.zip, 14 kB.
"Masking Unwanted Sounds", Nuts & Volts, September 2002. You
can download a copy of the article in Adobe pdf format, with
two jpg color photos, by clicking on
masking.zip . Size is about 310 kB. You can also download a copy
of the model 803 User Guide in pdf format by
clicking on USER803.ZIP.
"A High Performance Microphone Preamp", audioXpress Magazine,
October 2002. Download a 600 dpi scan of the article in Adobe pdf
format by clicking on preamp.zip . Size is
about 1.99 MB. You can also download a copy of the model 401 User Guide
in pdf format by clicking on USER401.ZIP.
"Build the CF-MOSFET Audio Power Amplifier" by G. Randy Slone,
Nuts & Volts Magazine, Feb-Mar 2003. This information has been
moved to our new Power Amplifiers page. Please click
here to visit it.
"Software for Audio Testing", Nuts & Volts Magazine, August
2003. You can download the audiotst.zip file by clicking
here. Download the full article as a 600
dpi Adobe pdf file by clicking here.
Size is about 2.94 MB.
"Bisbee Calling" was written for a specific newsletter but not published.
But it's an interesting audio-related article so I'm posting it here.
The zip file contains the text and color photos as an Adobe pdf file.
Click here to download it (about 314 kB).
"The MaxxBass Subwoofer" audioXpress, November 2004.
The MaxxBass* control unit is our model 907. For more information,
please click here to go to the 907 product
page. Please click here to download the
zipped circuit board layout and parts placement file (mbboards.zip).
(* MaxxBass is a registered trademark of Waves, Ltd.)
"Designing the Hot Strings Guitar for Chet Atkins" Multi
Media Manufacturer (a publication of Audio Amateur Inc.), May/June
2006. This took place between October or November 1975 and January 1977
but it took me 30 years to get around to writing the story. The article
includes photos and circuit diagrams. Click
here to download a copy of the article in "zipped" Adobe
Acrobat pdf format (size about 1.89 MB).
"A Multiple "Wall-Wart" Power Supply" audioXpress, June 2008.
This handy unit replaces ten DC output wall-warts in a 2RU rack-mount
enclosure. Each regulated output is isolated from the others and each
voltage is settable with two 1% resistors. Click
here to download the article in "zipped" Adobe Acrobat pdf
format. (Size: about 2.8MB) Click here to
download the full-size pcb layouts for this article. The layouts are
in CIRCAD .pcb format and they can be printed with a free version of
CIRCAD available from Holophase.
On January 14, 2010 the wallwart.zip file was updated to also contain
the Gerber files for manufacturing the two circuit boards. These files
are furnished "as-is" without warrantee of any kind -- please see the
readme.text file. (Size: 102 kB)
"TIM Revisited" Multi Media Manufacturer (a publication of
Audio Amateur Inc.), Nov/Dec 2008. In this article I take a look at
measuring Transient Intermodulation Distortion (TIM) in modern audio
power amps and it appears to be a non-issue with current designs.
The article includes photos and circuit diagrams.
Click here to download a copy of the
article in "zipped" Adobe Acrobat pdf format (size about 3.4 MB).
(The three photos did not scan too well so I included the original jpg
files in the zip file.) The zip file also contains a system overview, parts
list, circuit board layouts and the square-wave generator source code
that go with the article.
"Mysterious Data Errors" EDN, Tales From The Cube, December
15, 2009. In this article I describe troubleshooting and fixing a
digital data collecting system. The "fix" is good design practice in
all digital and low-noise audio circuits. Click
here to download a copy of the one-page
article in "zipped" Adobe Acrobat pdf format (size about 3 MB
-- it's a color scan).
"DIY Microphone Calibration" audioXpress, April 2009. This
hands-on tutorial shows you how to inexpensively calibrate a
microphone by the comparison method. I also describe calibration by
electrostatic actuator. Click here to
download the six page article in Adobe Acrobat pdf
format (size about 397 kB).
"All About Stroboscopes" audioXpress, December 2010. This
article reviews several commercial turntable rotational speed
measuring devices. It also describes a DIY LED stroboscope light
and two PC programs for printing stroboscope discs. These programs
with documentation are included in strobe.zip which you can
download by clicking here. Size about 1.6MB.
"Vertical Blending" by Don Walizer and Ron Tipton, audioXpress,
December 2010. The TDL® Model 4010 "The Restoration Preamp"TM has
a LR Blend Control for minimizing the noise from playing a lateral-cut
phonograph record by blending the right and left pickup cartridge
outputs. This article discusses whether blending is useful for playing
vertical-cut records. Download a pdf copy of the article by clicking
here. Size about 347 kB.
"Audio Testing With Noise" VoiceCoil, December 2010. This
tutorial investigates the use of randon and pseudo-random noise for
testing audio components and systems. Noise can be a very useful
test signal because it is inherently broadband which is faster and
perhaps more accurate than spot or swept frequency testing. Download
a pdf copy of the article by clicking here.
Download a copy of noisegen.zip (see Reference 11 on page 34) by
clicking here. Size about 3.4MB.
"Restoration of a Vintage Turntable" audioXpress, February
2011. In this article I describe the restoration of an early 1970's
direct-drive TT, the Netronics 350D. I reburbished the motor, rebuilt
the suspension and replaced the tonearm. This is a work-in-progress.
Since I wrote the article (January 2010), I've moved the tonearm
closer to the platter for better tracking. With a Sumiko adjustable-
azimuth headshell and Denon DL-103R MC cartridge, the performace is
greatly improved over the original product. Download a pdf copy by
clicking here. Size about 1.4MB.
"Modifying and Testing a Phase Meter Calibrator" CircuitCellar
website, July 2012. In this article I describe the modifications
I made to a DIY phase meter calibrator designed by Mr. Charles Hansen
and published in the November 2006 issue of audioXpress.
I then tested the calibrator using a precision phase meter and with
a time interval counter to measure the time between an amplitude zero
crossing of the reference signal to the amplitude zero crossing of the
phase shifted signal. I presented the measured results in tables.
An accompanying zip file contains the referenced circuit board designs
as well as the figures and tables which are rather small in the
The article contains a link to download this file or you may click
here for the download. Size about 736kB.
"A Vintage Turntable Revisited" audioXpress, September 2012.
This is a continuation of my previous turntable restoration article
(aX, 2/11). This time I built a new 20 inch tone arm which cuts the
tracking error in half compared to a "more standard" 10 inch arm.
I also used a fairly new material, carbon fiber tubing, for the new
arm. It's lighter than an aluminum tube with nearly five times the
stiffness-to-weight ratio. The carbon fiber tube presents some
interesting challenges. Download a pdf copy by clicking
here. Size about 1.2MB (contains color
I've included the following turntable review, published in the October 2012
issue of Sound+Vision magazine, because of the reviewer's
[favorable] comments about the carbon fiber tone arm. Download a pdf
copy by clicking here. Size about 645kB.
"Digital vs. Analog Equalization of Disc Record Playback" ARSC Journal,
Vol. 43, No. 2, Fall 2012. Traditionally, analog networks were used for
frequency emphasis during recording of other than acoustic records so it
followed that analog networks were used for deemphasis (equalization) for
playback. Some individuals are promoting the use of digital EQ for
playback saying that it is just as good -- but is it? This paper sheds
some light on the subject. Download a pdf copy by clicking
here. Size about 1.2 MB.
"Expert's Skills Evolve with Technology" audioXpress, January 2013.
This is an interview with Ron by Shannon Becker, Assistant audioXpress Editor.
Five pages with color photos. Download a pdf copy by clicking
"Update a Pair of MTX5i 5.25" Bookshelf Loudspeakers" audioXpress,
June 2013. The original design was weak in the mid-range frequencies so I
used simulation and measurements to replace the drivers and convert the
enclosures to sealed rather than ported. The overall frequency response
was improved. Download a pdf copy by clicking here.
"Build a Sound Level Meter and Spectrum Analyzer," audioXpress,
December 2013. This article describes my sound level meter and spectrum
analyzer designed around a Velleman Audio Analyzer kit (K8098). Nine SPL
ranges from 50 to 130 dB in 10 dB steps. Three position weighting switch:
FLAT, "C" and ITU-R ARM. A pdf copy of the aX article with construction
notes, a parts list, full-page drawings and photos are in the file
build527.zip. Download it by clicking here.
Size: about 3.5 MB.
"Testing a Tripath Power Amplifier," audioXpress.
March 2014. A Tripath or Class-T amp is a proprietary version of the
Class-D amp developed by Tripath Technology. This article looks at
two amps that use Tripath ICs: the TA2024 (15 W per chnnel) and the
TA2020+ (20 W per channel). These amps sound good but testing them
is a challenge -- this article explains how to do it. A pdf copy of the
aX article can be downloaded by clicking here.
Size: about 2.3 MB.
"Psychoacoustics," audioXpress. Part 1: "Audio Enhancing and
Spatial Location," June 2014. Part 2: "Noise Reduction and Sound
Masking," July 2014. Psychoustics is the scientific study of sound
perception -- we can hear sounds that are not really present or we can
not hear sounds that are present.
Download Part 1 by clicking
Download Part 2 by clicking
A companion CD of the article's
Addendum files (about 340 MB) is available free of charge by sending
an email to firstname.lastname@example.org with psychoustics CD in the subject line.
Please don't forget to include your mailing address!
"The Continuing Quest for Realistic Recorded Sound Reproduction,"
an audioXpress series beginning in the December 2014 issue.
Download a pdf collection of the articles to date by clicking
Each month's article has an associated file containing music examples,
and other "hands-on" information that can be downloaded from:
NOTE: Some of the zip files are rather large!
"Three-Way Loudspeakers with Active Crossovers," audioXpress,
Includes design and construction details and my acoustic measurement
data using the Dayton OmniMicV2 system.
Download the pdf file by clicking here.