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"Excellent rig. Needs a little work." How many times have you passed up a good deal because you were certain you'd never find the service information? How often have you sent your rig to the factory for a bug that you could have fixed if you had the documentation?
Q: Why do I need documentation for my radio equipment?
A: Unless you're an electronics genius, proper documentation is often essential to the repair or restoration of any radio equipment. Even a simple schematic can save hours of time that would be wasted otherwise.
Q: Okay, but is documentation readily available--even for my antique receiver?
A: Believe it or not, there is a good chance that documentation still exists for almost any radio you're likely to encounter. Your success in finding it, however, depends on knowing what type of documentation might be available for your particular piece of equipment.
Q: What types of documentation should I be looking for? Where can I find them?
A: Let's save the names and addresses for later and begin by taking a look at the different types of equipment documentation available. There are several:
Owner's Manuals: An owner's manual is supplied with the unit at the time of purchase. It's intended primarily as an instruction manual for the owner. It may not contain a schematic and service data is usually minimal. Although it's better than nothing, an owner's manual leaves quite a bit to be desired should a repair or alignment be required.
Manufacturer's Service Manuals: Service manuals are usually sold by the manufacturer. They contain vital repair, service and alignment data. Most manufacturers supply service manuals for their products, although some may not provide manuals for obsolete equipment. If you're working with old equipment, it's possible that the manufacturer may have gone out of business. Keep this in mind the next time you purchase a new rig. Obtaining a service manual will take a little extra effort, but you'll be making a worthwhile investment in the future of your equipment.
Third-Party Service Documentation: This type of documentation is is published by companies other than the manufacturer. It's available in several varieties from basic schematics to complete service manuals. While modern Amateur Radio gear is usually excluded, third-party documentation offers a wealth of information on antique receivers and modern consumer electronics.
Q: Wait a minute. You mean that there are companies that publish and sell service data for another company's products?
A: Certainly! Some of the most noteworthy publishers--past and present--include:
Howard W. Sams & Company Photofacts: Sams started publishing Photofacts in 1946 with only 12 employees. Today Photofacts are accepted as the standard for accuracy. Complete chassis photographs are included and each component is clearly labeled.
Alignment procedures and normal voltage readings are always
provided. The extensive Photofacts library does not include current amateur equipment, but you will find service data for Kenwood (and other manufacturer) radios that are seven years oldor older and also some of the classic shortwave receivers made by companies such as Hammurlund and Hallicrafters.
Photofacts are sold in numbered folders and volumes. To obtain the correct Photofact, you must find the reference number for your particular piece of equipment in the Photofact Index. If you have access to the world wide web, you can find their index athttp://www.dataview.com/photofacts/ Also be sure to check outtheir home page at http://www.hwsams.com
There is an interesting sidenote to the Photofacts story. Sams creates Photofacts from actual product samples. Instead of using the manufacturer's schematics, the circuits are analyzed and traced by Sams technicians!
John F. Rider Perpetual Troubleshooters Manuals: "Rider's," as this series is commonly known, was first published in 1930 and covered radios back to 1926. The first numbered volume, however, appeared in 1933. New volumes were published at a rate of about one per year until the last one, volume 23, appeared in 1953. (Rider's for TVs, however, went from 1948 to 1957, volumes 1 through 18.)
Rider's is indexed by a system that is very similar to the Photofacts. Several index volumes were published, such as volumes 1 to 7, 1 to 10, 1 to 15, 16 to 22 and 23 only. Unlike Photofacts, however, Rider used service data provided by the manufacturers.
RCA Victor Service Data Books, commonly called "Redbooks." These cover RCA receivers manufactured from 1923 to 1950. The first volume covered receivers from 1923 to 1928. A new volume was published each year until 1950.
Supreme Manuals: Compiled by M. N. Beitman, these first appeared about 1930 and covered radios made as early as 1926. One volume per year was published until the company went out of business in the 1950s. These generally contain only schematics; Riders and Photofacts are far more complete.
Hugo Gernsback's Official Radio Service Manuals: Six volumes were published from 1929 to 1936.
Mallory Radio Service Encyclopedia: First published in the early '30s, the Mallory Encyclopedias contained a very complete listing of radios by manufacturer and model number. In addition, an exact tube complement was given for each product. This information can be very useful if you are seeking service data for an old radio with an unknown model number.
Q: Speaking of tubes, what about vacuum tube data? Is that kind of information still available?
A: It sure is! Data for Eimac tubes, frequently found in amateur amplifiers and other high-power RF applications, is currently available from the manufacturer. Transmitting tube data can also be found in the ARRL Handbook; look in the Component Data chapter if you have a recent edition. Data books for other tube types, such as receiving tubes, have been published by several companies. Most of these data books are no longer in print. Copies, reprints and even old originals can still be obtained if you know where to look. Two of the most popular data books for tubes are:
RCA Tube Manuals: These are probably the most common tube manuals -- especially for receiving tubes. Separate manuals were also published for transmitting, special purpose and industrial tubes. These manuals first appeared in the 1930s and were frequently updated.
General Electric Essential Characteristics Tube
Data Books: These are similar to the RCA Manuals.
Tube substitution guides have also been published by Sams and John F. Rider.
Q: Now that I know what I'm looking for, where can I find the documentation?
A: If you prefer the manufacturer's service manual, start by contacting the manufacturer directly. If the manufacturer is out of business, or no longer supplies the manual you need, you have other options. For example, try obtaining a copy from a manual-supply company.
If you're working with military gear, manual-supply companies are also good sources. And, some military equipment manuals can still be obtained from the government. (More about that later.)
If you think a Photofact or Rider might be available based on the age and type of equipment involved, check with your local library. Many city and university libraries have them and will let you make photocopies provided that no copyright laws are violated.
If your local library can't help you, try one of the "schematic services" that cater to antique radio buffs. Their prices are generally quite reasonable. Don't forget to check the hamfest flea markets and yard sales. Service information can turn up in the most unusual places!
For a difficult case, you might try a classified ad in QST. A classified ad in a publication that specializes in the type of equipment involved (such as Electric Radio Magazine\1/ or Antique Radio Classified\2/ for surplus or antique rigs) may be very effective.
ADDRESSES
Q: Come to think of it, I have several radios that could be put to good use--if they were working! How about those addresses you promised?
A: Here they are. Good luck with your projects!
You can get a photocopy of any ARRL published article for $3 ($5 for nonmembers) for each article requested. Contact the ARRL Technical Department (reprints@arrl.org ), 1-860-594-0390) if you wish to get photocopies.
This information was prepared as a membership service by the American Radio Relay League, Inc., Technical Information Service, 225 Main St., Newington, CT 06111 (860) 594-0214. Email: tis@arrl.org (Internet). ARRL HQ is glad to provide this information on the Web free of charge as a service to League members and affiliated clubs.
If you have any questions concerning the reproduction or distribution of this material, please contact:
