These are items that I was looking for, and found.

Apple 2 IC Card
AC Adapter for Boris Electronic Chess Computer
Operations Manual for FR-114/U Frequency Counter
Texas Instruments LED Watch
Software for HP 9836
Seven Segment Displays
Knobs for Lafayette Explor-Air Receiver
Motorola 14500B Industrial Control Unit
Realistic DX-150 Shortwave Receiver
Manual for Heathkit CI-1079 Tachometer
HP Microprocessor Lab Manual
Manual for B+K Model 1450 Oscilloscope
Out-of-Print Books

I was looking for documentation and software for this card and integrated circuit holder combination that appears to fit in an old Apple 2 computer.

Click here for more information.

A kind reader sent along the following:

Hi Dan, I got mine working after a spell of 25 years...and it helped me fix a couple of Apple 2 motherboards.

It is a "FAIRY" IC chip tester, the manual and disk are here.

I have a Boris Electronic Chess Computer without an AC adapter, so I was looking for the proper power supply to go with it.

I've got more information about this game, along with an on-line manual, here.

Several kind souls wrote in with information, and I managed to find another Boris unit with an AC adapter.

The adapter is marked as 10 volts AC but actually provides about 13 volts AC. Output is on a mini-jack connector.


I have an FR-114/U frequency counter made by Winslow Electronics and, as usual, was looking for manuals.

A kind person in Wisconsin sent me a military manual with the sections relevant to the FR-114/U.

I'm still looking for a Service Manual.

I found an old Texas Instruments (TI) watch, a TI-500. This is a mid-1970's era wristwatch that displayed the time using four red LED's when a button was pushed. It was the first digital watch I owned (I received it as a gift).

This particular model has an all-black case with a round red lens. A thin silver ring surrounds the lens. The lens itself has "Texas Instruments" embossed in the red plastic. This model is referred to as "Series 500."

After all these years the crystal appears to have aged, since the watch appears to gain many seconds each day.

I now have two Hewlett-Packard 9836C desktop computers that boot up and wait for an operating system.

The 9836 is an early 1980's vintage industrial/laboratory computer based on the Motorola 68000 processor. It came out of the Fort Collins HP facility and had a ROM version of "Rocky Mountain BASIC".

I picked up the second machine and it came with some documentation and several 5.25-inch floppy discs. One of those discs has a BASIC 2.1 System on it, which works fine.

I am still interested in finding more software, ROMs, and documentation for these machines!

I was looking for four (4) replacement displays, to be used in the seconds and tens-of-seconds positions in two identical time code display units.

The display measures 7/8-inch high by 7/16-inch wide and contains seven incandescent segments. The display itself is not a tube, as a normal numitron would have. This has a flat glass front and square sides, shaped much like an integrated circuit package.

It has 13 pins in a DIP (dual in-line package) configuration, six pins in one row and seven in the other. This makes it similar to a minitron in appearance but somewhat smaller in pin count (minitrons typically have 16 pins).

The display is stamped "5GZ FFD71F" on one side. Based on reader input, this may be a FFD-71 display made by IEE.


I ordered four displays from Allied Electronics. They arrived in a few days and worked just fine. They're physically a little bit different than the originals -- somewhat thicker and taller -- but the actual display image is identical.

I have a Lafayette Explor-Air super regeneration receiver that was missing two of the small knobs from the front when I acquired it.

My copy of Shortwave Receivers Past & Present indicates that the Explor-Air (KT-135) was manufactured from 1958 to 1970 and that "[D]ifferent knobs were also featured over the long production life of this model."

A kind person saw my Wanted page and offered a pair of knobs that matched perfectly.

Many years ago Motorola manufactured a one-bit CPU, the 14500, that was about as simple as you can get and still have a processor.

I'd like to find the development/demo kit that Motorola produced for the MC14500B (the DS14500A Industrial Control Unit Demonstration System), and any of the 16-pin CPU parts themselves.

I did manage to locate a Demonstration System, which you read about here.

I have moved this information to a separate page, which you can view by clicking here.

I picked up a game entitled Passing through the Netherworld, which is a well-researched version of the ancient Egyptian game of Senet.

I've scanned some parts of the game and put them here.

I'm looking for a manual for this Heathkit tach. I'm not sure of the model number, since there's no tag on it, but it might be a CI-1079 based on Heathkit's Spring 1977 catalog.

Internally, the main PC board has a part number of 85-1618-4 silkscreened on the top and 85-1618 on the underside.


Bought a manual at a nearby hamfest ("boot sale" for our U.K. readers).

Update redux:

Bought a second manual along with the instructions for the Induction Pickup Accessory (Model CIA-1079-1). From the introduction:

This Induction Pickup Accessory allows you to use your Heathkit Model CI-1079 Digital Tachometer on solid-state ignition systems, capacitor-discharge ignition systems, or on other systems where points are not available or accessible.

I have a Hewlett-Packard 5036A Microprocessor Lab in a Samsonite briefcase that appears to work but I don't have any documentation for it.


I purchased a second HP 5036A and it came with a 450+ page manual entitled Practical Microprocessors, HP part number 05036-90003. I purchased a second copy from a used bookstore, so now each Lab has an accompanying manual.


I purchased another 5036A from a former Hewlett-Packard employee. This appears to be different than the usual model in that it has a ZIF (zero insertion force) socket for the ROM.


Speaking of ROM, click here for an assembly listing of the 5036A monitor ROM or here for an assembler output listing.

Here are three built-in demonstrations to run on the 5036A:


I have an old B&K model 1450 Diagnostic Oscilloscope but I don't have a manual for it.

I ordered a manual from and it arrived a few days later. They bought out the parts and copyrights on the old B+K products and appear to be doing a brisk business. Friendly service and very responsive.

Click here to see a brief review article from the November 1968 issue of Electronics World. (A larger version is available here.)

Now I just need some probes for it...

I was looking for the following out-of-print books:

H-8 Programming for Beginners, Ron Santore, Don Inman and Bob Albrecht

I'm always on the lookout for old computers to rescue, including those made by Heathkit. One early model is the H-8, an Intel 8080-based desktop computer introduced in 1977. Besides the hardware and software, I'm also interested in documentation and reference material for these old machines.

Dilithium Press published this title in 1980. From the back cover:

This book is a short programming course that will lead you step by step into the basics of computer programming. Specifically designed for use with the Heath H-8 computer, it not only covers assembly language programming but also Benton Harbor BASIC. As you go along, everything is defined for you, and in each chapter you write a program or subroutine. In this way you are introduced to only a few new programming instructions at a time. This is a book of basics, not techniques, so you will not need a background in computers, electronics, or programming.

OR in World War 2: Operational Research Against the U-Boat, C. H. Waddington, 1973, ISBN 023615463X

I finally received a copy of this title in December 2006. I first ran across a reference to it in The Pleasures of Counting.

From the Preface:

Operational Research has by now become an important factor in management, not only in military contexts but for industry. With its wider acceptance has come, inevitably, greater specialisation; most publications about operational research are devoted to the study of some rather particular detailed problem. The general character of a discipline, which is what students need to learn, is perhaps better exemplified in its first phases of development, when its principles are first being worked out, and there is not too much detail or backlog of professional infighting to obscure the main outlines.

Elements of Networking Style, Mike Padlipsky

I received an e-mail in July, 2000, informing me that had just come out with a "backprint" of the title. I ordered it on the web and it arrived about two weeks later.

As an aside, Mike's writing style is, shall we say, unusual. His ideas have merit, but it takes some work to filter through the commentary and get to the nuggets.

Mad Scientists' Club, Bertrand Brinley

I moved theinformation regarding the Mad Scientists' Club to a separate page, which you can see by clicking here.

Brinley also wrote a non-fiction book in 1960 called Rocket Manual for Amateurs. I found a copy in a used book store.

(Click here for more information on a radio-based model rocket locator.)

Inside the TRS-80 Model 100 by Carl Oppedahl

I received my first TRS-80 Model 100 as a gift in 1983, and it's been a favorite ever since. Other laptops surpass it in many respects, of course, but it is rugged, has a real keyboard, boots up instantly and is easily programmed in BASIC. I even used it once to brute force a password on an HP-2000F system via the built-in modem!

I'm interested in these "classic" computers and was was looking for a book by Carl Oppedahl entitled Inside the TRS-80 Model 100. It finally found a copy via websearch at Title Wave Books, a used book store in New Mexico. It showed up a few days after ordering.

The Model 100 is not Year 2000 compliant -- the date that appears on the main menu is hardcoded to show a century value of "19". There is a software patch to correct this problem, which can be found here.

I am looking for parts and accessories for the Model 100, which you can see listed here.

Paladin card front Paladin card back The Model 100 (and follow-on Model 102) were occasionally used as part of a larger system or product. One such product was the Paladin Measuring Systems "Measuring Calculator".

Calculator User Guide and Directory, Charles Sippl

I'm interested in old calculators, primarily from the 1960s and 1970s, so the Calculator User Guide and Directory by Charles Sippl has proven to be a useful reference. It covers essentially every commercially available handheld and desktop calculator available during the early to mid-1970s.

Cheating at Cards, Bryan Clough

Cheating at Cards by Bryan Clough discusses various weaknesses in credit card systems. Jeff Moss recommended it a while back, and I eventually ordered in from Amazon UK. It took nearly five months to arrive here in Maryland.

Programmer's Guide to the 1802, by Tom Swan

Back in the late 1970's there were a series of single-board computers that were built around the RCA 1802 microprocessor. At the time I was never fortunate enough to own one of those Elf or SuperElf machines, and so never had the opportunity to program the 1802.

A few years ago I was doing some reverse engineering on some cellular telephone firmware that ran on an 1806, a later version of the classic 1802. I located an old RCA databook with the mneumonics and wrote a disassembler, but the online references at the time suggested a book by Tom Swan entitled Programmer's Guide to the 1802. I eventually located the title via an on-line bookseller.

Besides a clear explanation of the 1802 itself, the book also provides code for an 1802 assembler.

Now I just need to find someone who is getting rid of their Elf or other 1802 single-board computer and I'll be able to do what I couldn't do 30 years ago.

For more information about the RCA 1802 microprocessor, click here.

U.S. Navy Bureau of Ordnance in World War II, Department of the Navy

A 500+ page book that details the history of the Bureau during World War II, including the persistent torpedo problems that plagued submariners during the early part of the war.

ZAP! The Rise and Fall of Atari, Scott Cohen

Like many game players in the 1970's, I put a lot of quarters into arcade games - including many made by Atari. Later I bought an Atari 2600 game machine with many of the "classic" game cartridges.

This book chronicles the history of Atari and its founder, Nolan Bushnell.

You can read a review of the book here.

Radionavigation Systems, Boerje Forssell

Excellent descriptions of various radio-based methods of location and navigation. Originally recommended by Phil Karn.

Paperbytes Bar Code Loader, Ken Budnick

A method for microcomputer program entry from 1977.

One of the most common problems for users and suppliers of personal computer software is the need for product distribution in a form which is helpful to the user, low in cost, tolerant of errors in production use, and free of the need for expensive highly specialized peripherals. One solution, conceived in detail by Walter Banks of the Computer Communications Network Group at the University of Waterloo, Ontario, Canada, is the use of bar code patterns prepared on a computer-controlled typesetter. A bar code is a linear array of printed bars or varying width which encodes digital data as alternating patterns of black ink and white paper. By using a ruler as a guide, an inexpensive handheld "wand" scanning unit converts the bar patterns into a time-varying logic level signal. This time-varying binary value can then be interpreted by a program which understands the format of the bars.

The purpose of this pamphlet is to present the decoding algorithm which was designed by Ken Budnick of Micro-Scan Associates at the request of BYTE Publications Inc. The text of this pamphlet was written by Ken, and contains the general algorithm description in flow chart form plus detailed assemblies of program code for 6800, 6502 and 8080 processors. Individuals with computers based on these processors can use the software directly. Individuals with other processors can use the provided functional specifications and detail examples to create equivalent programs.

Notes on the Network

This document is mostly of historical value, being the reference document for the long distance telephone network prior to the court-ordered break-up of the phone company ("Ma Bell") in 1982.

An electronic copy of this book, along with a number of other historical documents related to the telephone system, can be found here.

Flying Your Bell Model 206 JetRanger

A companion to the Pilot's Operating Handbook (POH), this publication provides an overview of piloting the iconic single-engine turbine helicopter.
The Trigrams of Han

A discussion of the history and organizational structure of the I Ching, an ancient Chinese wisdom tome.
Error Detecting Decimal Codes

Mathematical methods for detecting errors in transmitted information.
The Digital Electronic Watch

A 1978 book describing LED and LCD wristwatch technology. It includes a long appendix describing battery replacement and setting instructions for a large number of different watches.
From CPU to software

A 1974 publication from Intel introducing the 8080 microprocessor:

The 8080 Microcomputer is here! It is the first high-performance, n-channel, single chip microprocessor available with a performance matched circuit family and software backup. It is also the only microcomputer available that is supported by over a 100-man-years of microcomputer, systems, software and engineering experience.

The 8080 would go on to be used in the first generation of hobby computers, many of which I am interested in rescuing.

Click here to go back to the main page.
Comments to Dan Veeneman
Updated June 25, 2019