My friend who is a member of the phreaking community gave me this site which, he thinks contains information about the number you traced the caller
to. I'm still not sure who could use this to call you. The telephone company definitely has the ability to and maybe phone hackers do too. Now I'm
not positive this is the explanation.
5.1 What are test numbers?
Test numbers are dialups to testing equipment or test features set up by the phone company or private entities. There are about a billion kinds of
test numbers, so PLEASE don't just start asking for test numbers, especially on newsgroups like comp.dcom.telecom.tech.
5.2 What are some common test numbers and their uses?
- 5.2.1 Sweep Tones: Tone sweeps are a test tone ranging from 304hz to 3204hz. A common use for sweep tones is to check for infinity-transmitter style
taps. Dial up a sweep tone. If an audible clicking is heard during the sweep then a transmitter could be installed on your line. Telco maintenance
uses sweep tones to check for the presence of loading coils, and other such nasties that eat high frequency tones in order to qualify a line for high
speed services.
- 5.2.2 Milliwatt test: These are 1004 hz tones sent out at 0 db. Milliwatt tests are used to check for line loss and other complex tests.
- 5.2.3 1004 hz test tone: This is a vanilla 1004 hz tone. Nothing too useful here, without a loop analyzer anyway.
- 5.2.4 Quiet termination: This feature connects the caller to a port with fixed resistance, 600 ohms or 900 ohms being the most common. There should
be nothing but dead silence on connection. Clicks, static or crosstalk will be clearly evident if a noisy line is used to dial this test.
- 5.2.5 Ringback: Calls back the originating number in an annoying fashion. Dialing all the touch-tone digits in order (starting with 1 and ending in
# going across the keypad rows) will generate 2 tones saying the keypad is ok.
- 5.2.6 Loops: These numbers exist in linked pairs. Call one number and youíll get a tone. Call the other number and you get dead silence. If both are
called at the same time they make a connection. It used to be that you could then talk over this connection, but now there are filters that block
speech placed on most loops.
- 5.2.7 ANAC: This test dialup will read off the number of the line youíre calling from. On rare occasions you will find ANACs with a DTMF response
for use with remote test terminals.
- 5.2.8 DATUs: DATUs (Digital Audio Test Units) are a godsend to technicians and phone phreaks everywhere. DATUs allow a caller to monitor lines
(don't get too excited), open and short pairs, and put trace tones on the pair. While it might not sound too exciting, it has more applications than
most people think.





That's kind of "out of the
ordinary" in itself!