Frequently Asked Questions


Scroll down or click on the following links for answers.  Click "[Back]" to return here.

How do I ask a question about using the Library? 

How do I ask a question about phone features or repair?

What should I do if I can't find a document I want?
What is a BSP?
What is a schematic?
How much is my phone worth?
When I click on an item in the LATEST ADDITIONS List why don't I see the document?
How can I email a link (URL) that will download a single file from the Library? 


Q: How do I ask a question about using the Library?

Simply click on the "Contact Us" link in the Menu Bar and ask away! You're also welcome to make any positive suggestions for improving the site.   [Back]


Q: How do I ask a question about phone features or repair?

Ask TCI members for help using the Listserv:    [Back]


Q: What should I do if I can't find a document I want in the Library?

Don't expect to find every document you might want here. Even though we have a lot of documents, there are many, many more that we need to find and add. Make a "wanted" post to TCI members using the Listserv. If someone has the document and you ask nicely, they may volunteer to scan and contribute it.  [Back]


Q: What is a BSP?

A Bell System Practice (BSP) is a document in a standard format that provides technical information on Bell System Products. BSPs are extremely useful documents to collectors, as they contain loads of information on product features, ordering options, colors, wiring, maintenance and other technical details. They cover small components to large systems and even policies and procedures used by installers.

Thousands of BSPs were produced in several sizes from the early 1930s until the break up of the Bell System in 1984. Several different numbering and organizational schemes were used. AT&T and Lucent published revised practices into the 1990s.

As products matured and changed, BSPs were revised and reissued with new Issue numbers. New models or product variations were introduced and old ones were retired during a product's lifetime.  To fully understand a product, several issues of a particular BSP must often be consulted.

Please contribute copies of any BSPs that aren't in the library. Our goal is to archive as many different issues of each BSP as possible.

More information on BSPs may be found on this site:

Similar technical "practices" were produced by other companies worldwide, including AE, GTE, Stromberg Carlson, Ericsson, Bell Canada, Northern Telecom and others.   All are welcome in the Library!  [Back]


Q: What is a schematic?

A schematic is a diagram that represents the elements of a system using abstract, graphic symbols rather than realistic pictures. A schematic usually omits all details that are not relevant to the information the schematic is intended to convey, and may add unrealistic elements that aid comprehension. (Wikipedia)

Schematic wiring diagrams were often provided to installers to help make them more productive when wiring phones and setting up configurable options. Collectors often use them as a first tool when troubleshooting a phone, then consult the detailed technical documentation as needed.

"Browse" in the Menu Bar provides quick access links to wiring diagrams.  Others can be found in BSPs, especially those with "Connections" in the title.  [Back]


Q: How much is my phone worth?

The TCI Library does not offer pricing opinions.  Here are some general comments.

Don't expect an easy answer to the question of value.  There are no fixed prices or accepted price guides in phone collecting.  Price guides you may find in books are someone's opinion and usually way out of date.

A lot depends on condition.  A beat up, as-found, untested example may sell for under $10. 
Like new examples of the same set may sell for hundreds or even thousands of dollars.

Most phones made after 1920 were produced in quantities of millions, so aren't particularly scarce.
Even phones that look unique or are seen described as "one of a kind" were usually made on a production line.

Many phones were refurbished many times and often contain replacement parts, which may impact the value.
Within a model, color and optional features can often add to the collectibility of a particular phone.

A patient collector can find one eventually at a low price.
Others are often willing to pay more to get a particular phone quickly.

You can usually get a good general idea for current prices of common phones by checking catalogs and on-line sites that sell phones and on-line auction sites.

Remember to compare phones with like condition.
A phone that has been refurbished by an expert is worth at least 3 to 6 times the price of an "as-found" phone.
Understand whether the phone has all original parts, replacements from the same or a generic maker or modern reproductions.

If you aren't sure about the scarcity of a phone, don't even think of buying it as an investment.  Do your research, and enjoy what you buy.

For more details, we welcome you to join the TCI List Server and ask the membership about your phone.  Select TCI Sites / TCI List Server from the black menu bar.  [Back]


Q: When I click on an item in the LATEST ADDITIONS List why don't I see the document?

Your click takes you to the category of the selected latest addition.  If the sort order is by Date, Descendant the file should be near the top of the list.  (On the "Order by:" line Date is highlighted and the word [Ascendant] is visible.)  Documents are listed AFTER any subcategories.

If results are presented in a different order, click on Date and Descendant.  When through, Date is highlighted and the word [Descendant] is replaced by [Ascendant].

HINT: Recent additions by contributor can easily be found by entering the contributor's name in a search box, click on FIND and make sure the results ordering is "Newest First."

Similarly, recent additions in your favorite categories are found by browsing to the category, then ordering results by "Recents First."  [Back]


Q: How can I email a link (URL) that will download a single file from the Library?

It's often handy to email a reference link that enables the recipient to quickly see a single file.  To create the link, use the following procedure:

  1. All URLs start with this base:
  2. Add the filename, which is found on the Details page for the desired document.
  3. Email or post the resulting URL.

      EXAMPLE:  To send a link for the wiring diagram of a 500D set, browse or search to the document entry in the Library:  Copy the filename (500cd_tl.pdf) and add it to the base (from 1. above) to form the URL:

HINT: Save the base as a favorite in your browser. When creating a link, open it in a new window, copy and paste the filename in the browser’s navigation line, then hit return. If the file downloads properly, the link is correct. Copy and paste it to the email or document.  [Back]


Questions from the TCI listserv that we hope to answer in the future:

(Many of these topics and much more are discussed regularly on the Listserv and covered in Singing Wires articles.)

What kind of phone is this?
Who made it?
When was it made?

How to remove the fingerwheel?  [Hint: Search for "remove fingerwheel"]

Why won’t my phone ring?
How to make my phone ring louder (adjusting gongs)
Why does my phone tingle when dialing on another phone on the same line?
How many ringing phones can I have connected at the same time(REN)?

Why won’t my phone dial?
How to eliminate clicking noises when dialing?
Lubricating stuck and/or slow dials
Why my touch tone dial doesn’t send tones? (polarity sensitive, etc.)

Why doesn’t my phone talk louder and what to do to fix it
Hissing and crackling transmitters
Use of DSL filters
How to diagnose a bad handset cord
Phones that don't transmit or receive due to depressed contact springs in the handset cavity

Buffing  Bakelite
Fixing cracks in plastic phone housings


Recent Contributors

Thanks for new documents from David Gruger, Jeff Lamb, Walt Aydelotte, Dennis Hock, Steve Flocke, Paul Wills, Sam Etler, Fred Haynes, John Novack, Clint Gilliland, Steve Cichorsky and Karl Brose.

Please add your name to this list!

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