Software Download

Last updated: 5 December 2016

ASC2AHEX.ZIP, Size: 18.4 kB, TDL freeware
Program (C source and executable) converts a column-of-numbers file in ASCII format to another file in ASCII-Hex format. We wrote this program especially for creating EEPROM programming files for our model 109 Audio Generator so the file length is limited to 5000 values but this can be changed if needed. You can also select 8, 12 or 16 bit resolution for the output file. (Requires ANSI.SYS)

RS232.ZIP, Size: 3.8 kB, TDL freeware
ASCII text and programs of "Add an RS-232 Output to any PIC Microprocessor",Electronic Design, May 12, 1977.

BUTTERBP.ZIP, Size: 49 kB, TDL freeware
(Updated 21 Dec 2008)
Program (C source and executable) designs all-pole Butterworth bandpass filters. Parts values are computed for a low-sensitivity design using three opamps and for a biquad circuit also using three opamps. User input is center frequency, bandwidth, number of pole pairs, center freq. gain and a value for the capacitance "C". Component values display on screen and can be printed. With documentation as a pdf file. (Requires ANSI.SYS)

LOW2UP.ZIP, Size: 10 kB, TDL freeware
This program (C source and executable) converts lower case letters in an ASCII text file to upper case. Numbers and punctuation are unchanged. (Requires ANSI.SYS)

WAV2ASC.ZIP, Size: 44 kB, TDL freeware
This package contains C source and executables for three programs. wav2asc converts single-channel (mono) WAV files to a list of floating-point numbers in ASCII characters. asc2wav converts a list of numbers to WAV format, and normasci normalizes an ASCII number list file so peak values are no greater than +1 to -1. (Requires ANSI.SYS) NEW version (1.3) of wav2asc fixes a header bug (Oct 2001).

WAVHEDR.ZIP, Size: 14.3 kB, TDL freeware
Reads and displays WAV file header data. Calculates and displays playing time. Updated version (2.0 - 05/13/01) now supports Microsoft ADPCM format files. C source and executable. (Requires ANSI.SYS)

HIGHOFF.ZIP, Size: 10 kB, TDL freeware
Clears the high bit of every character in an ASCII text file. (I wrote this because a certain unnamed word processor SET the high bit in every character when writing an ASCII text file.) ANSI.SYS required.

TDL_IRD.ZIP, Size 12 kB, TDL freeware
New, "C" language software for Terry Weeder's "IR Remote Control" article, Nuts & Volts Magazine, Feb 1998. He described a VERY useful, general purpose IR remote control decode circuit using a PIC16C54 but his assembly language software is hard to modify. Our C version is well-commented and is portable. Includes source, hex file and documentation. Circuit board layout and Gerber file added Mar 24, 2000.

PPED.ZIP, Size 11 kB, TDL freeware
"Passive Phono Preamps - A Universal Network," by Mr. Paul Stamler was published in the Dec '01 issue of AudioXpress. The author included a spreadsheet program which calculates the values of the passive network components in a "trial and error" manner: you enter the component values and it calculates the frequencies. I rewrote his spreadsheet equations into a small "C" program which accepts the frequencies and a value for R1 and then calculates C1, C2 and R2. This is a bit more convenient I think. Includes source code. Sep 5, 2002., Size 19 kB, TDL freeware
This zip file contains a pair of programs: PZNET and RCNET. PZNET calculates the series R and C values for an entered pole frequency, zero frequency and input R. RCNET calculates C for an entered R and frequency. For documentation, please refer to the User Guide for our model 407 Stereo Phono Preamp. PZNET was used to calculate the component values for the turnover networks and RCNET for the rolloff networks. You can download this user guide by clicking here. includes "C" source for both programs. Nov 16, 2002., Size 8.3 KB
This file contains the circuit board layouts that go with the article A Multiple "Wall-Wart" Power Supply, which has been accepted for publication in AudioXpress magazine. This unit replaces ten DC wall-warts with a rack-mount supply. Each output is isolated and regulated and has lower hum and noise than the wall-warts it replaces. The layouts are in CIRCAD .pcb format which can be printed with a free version of CIRCAD from
Jan 2, 2008., Size 90 kB
This file contains a system overview, parts list, circuit board layouts and the square-wave generator source code that go with the article TIM Revisited which has been published in Multi Media Manufacturer magazine, Nov/Dec 2008. (See contents.txt for a list of files and contents.)
Aug 30, 2008., Size 54 kB
This file condtains the "C" source, executable, library and readme.txt for a program to measure the dynamic range of a 16 or 24-bit mono wav file. This is the revised 3.0 version as of Dec 2016. It's a DOS program with a GUI, and it runs in Windows 2000, XP and 7 -- see instructions in readme.txt. You can easily make a mono version of any stereo or multi-channel file with an audio editor.

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You can find more software to download on The magazine article reprint page,