Frequently Asked Questions on Caller ID

Question: How do I set the time and date?

Answer: The time and date on a Caller ID are normally set by the Caller ID information sent by the telephone company; there is not usually a way to set the time and date manually.

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Question: Do you have any technical information on the Caller ID Call Waiting signal?

Answer: The Caller ID Call Waiting alerting signal consists of two signals -- SAS and CAS. The SAS signal is 440 Hz for 300 ms followed immediately by CAS. CAS is a DTMF (Dual-Tone Multi-Frequency) signal -- 2130 Hz and 2750 Hz for 80 ms. If the telephone line has distinctive ringing on line, the SAS signal may be altered to mimic the ringing pattern of the line that the Call Waiting call is coming in on.

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Question: Why do I not get my Caller ID or Call Waiting ID information?

Answer: The problem may be due to several factors. The questions below cover the major culprits behind this problem.

Are you answering the phone before the second ring?: The Caller ID and Call Waiting ID information is sent by the telephone company between the first and second ring; be sure to let the telephone ring or send the call waiting signal at least twice.
Are you subscribed to the correct service(s)?: If you are waiting until the second ring or later to answer the telephone and are still not getting the Caller ID information, call your telephone company to be sure you are subscribed to the Caller ID service. If you still are not getting the Call Waiting ID information, call your telephone company to be sure you are subscribed to all three of the following services: Caller ID, Call Waiting, and Caller ID Call Waiting.
How many devices do you have connected to your telephone line?: Check the Ringer Equivalence Number (REN) on each device and add all of the REN's together. If the number is higher than 5, then you have too many devices on the telephone line, and the signal is not strong enough to activate the Caller ID unit. If the number is higher than 4 (in a suburban area) or 3 (in a rural area), you may still have too many devices on the line. However, the only way to determine this would be to remove devices to lower the REN or to contact the telephone company to determine the maximum REN for your area.
Have you confirmed that the problem is in receiving the signal and not in the caller ID unit?: If you are only using one Caller ID, you may simply have a bad unit. If you have multiple units, be sure that they are designed to work with other Caller ID units on the same line (some are not, others require that a switch be set).

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