Introduction:

The main function of the Tap Nullifier is to DEFEAT commonly used methods of interception of telephone, and fax communications, such as automatic tape recorder activators, automatic line transmitters, etc.

Such devices are rather hard to DETECT, although many "magic boxes" equipped with dials, meters and LEDs CLAIM to detect them.
Generally they WILL detect ONLY that someone has picked up an extension telephone on the same line.... Hence, ALL that "magic boxes" will do is create a false sense of security.

Although sophisticated test equipment is capable of detecting the vast majority of wire tapping devices, such detection can only be accomplished by a SKILLED countermeasures technician and ONLY in a "test mode", that is, with the telephone DISCONNECTED from the line.

Even IF an illicit device is detected, there is no guarantee that a new one will be installed 5 minutes after the technician declares your line to be "clean".

The important thing to remember is: "magic boxes" plugged into your phone line will NOT detect ANYTHING else than MAYBE another telephone off-hook on your line.

The logical alternative therefore is to DEFEAT eavesdropping devices.

Design philosophy of the Tap Nullifier

The technology for defeating eavesdropping was first used in the X2 secure telephone, designed by Viking International in the mid-1980's and marketed for many years. This telephone received rave reviews from several leading experts.
From our experience in secure communications we continued to "fine-tune" this technology and we made refinements and improvements based on new technology as it became available.

One of the paramount considerations from day 1 was that an EFFECTIVE defeat-system should NOT be powered off the telephone line. For example, whereas it is true that series-type illicit devices can be "detected" to a certain extent by Voltage measurements, the whole purpose is rendered ineffective by powering the measuring instrument off the telephone line being tested, since the measuring instrument ALSO consumes power, just like the device you are attempting to "detect....
Although the above example refers to "detect" schemes, not to "defeat", it is just poor engineering practice to power ANYTHING off a telephone line.

Lastly, after reviewing other manufactures' approaches to a defeat system, it was decided that their using a simple switch to switch from "normal" to "defeat" operation was NOT an effective way to ensure proper operation.
We feel that such a simplistic approach does NOT guarantee proper operation under ALL circumstances because not all telephone lines have identical characteristics. In fact, under some circumstances, the "simple switch" approach will not work at all.

The Tap Nullifier dos NOT draw power from the telephone line and allows you to "fine-tune" it to the specific characteristics of YOUR telephone line, so you are assured that it is 100% operational.

THE TAP NULLIFIER IS DESIGNED AND MADE IN THE USA

Please take ample time to fully read and understand these instructions. It will help you realize the Tap Nullifier's full potential and will avoid unnecessary frustration and questions. In our experience, 99% of all "problems" result from NOT READING all information.

Step 1. Initial set-up and connections to your telephone line.

A. BEFORE connecting ANYTHING, please be sure that all 3 switches are in their "down" position.
B. Plug the AC adapter (supplied) into a wall outlet. (Note: Use only the AC adapter supplied. Other adapters may cause improper operation. The adapter is 12VDC, center negative, 200 ma)
C. Plug the connector at the end of the AC adapter into the jack marked "POWER" on the rear panel of the Tap Nullifier.
D. Unplug your telephone from the telephone wall jack and plug the telephone into the jack marked "PHONE".
E. Connect the modular phone cable (supplied) between your telephone wall jack and the jack marked "LINE" on the rear panel.
F. Now pick up your telephone. You will hear the dial tone. Your telephone now functions as it normally does.

Step 2. Making and receiving normal (non-secure) calls.

After your call, you can leave S1 in the "ON" position to monitor your line Voltage.
After you hang up and with S1 "ON", the red LED L4 will go off, green LED L2 will come on and green LED L1 will stay on. Voltmeter will read 46-52 Volts.
With your phone ON hook and S1 "on", you can monitor the following conditions:

1. Another phone on the same line is picked up. Voltmeter will read 6-10 Volts; green LED L2 will go off, red LED L4 will come on.
2. An "infinity transmitter" (a remotely controlled eavesdropping device that allows an eavesdropper to listen to your ROOM conversations through your telephone line) is activated. This may occur typically immediately after someone calls and says "wrong number"...!!! When an infinity transmitter is activated, the Voltmeter will typically read approximately 15 Volts. The green LED L2 will go off and red LED L4 will come on.
3. A lineman's test set in active mode has been attached to your line. Green LED L2 will go off, red LED L4 will come on and the Voltmeter will read 6-10 Volts.

Step 3. Set-up procedure for the secure (defeat) mode.

1. Place ALL switches in their "down" (off) position. Leave phone ON -hook.
2. Place S1 (SYS) in the "up" position. Green LED L1 will come on; green LED L2 will come on, the Voltmeter will read 46-52 Volts.
3. Using a small screwdriver, turn control C1 (LEVEL) fully counterclockwise. DO NOT FORCE!!
4. Take the telephone off-hook and place switch S2 (SEC) in the "up" position. Green LED L2 will go off, red LED L4 will come on, and voltmeter will read 6-10 Volts.
5. SLOWLY/GENTLY turn control C1 clockwise while observing red LED L4.
6. When red LED L4 goes off, green LED L2 will come on and voltmeter will read 24-26 Volts or more.

The secure mode has now been properly set and will not require readjustment UNLESS you want to install the Tap Nullifier on a DIFFERENT telephone line.
NOTE: If you turn control C1 too far clockwise, past the point where green LED L2 comes on and red LED L4 goes off, you may loose dial tone.

You may now proceed to make a call.

NOTE A. After the secure level has been properly set, per above, you can at any time during a normal (non-secure) call, switch to "secure" (defeat) by placing S2 in the "up" position.
NOTE B. On some types of telephone systems you telephone may not operate in its "tone dialing" mode when the "defeat" mode is activated. If this happens, you can:
a. Use pulse (rotary) dialing
b. Use a small portable tone dialer held to the microphone of the handset.
c. Dial out in the non-secure mode then flip S2 to the "up" position before starting your conversation.

If at any time during a secure (defeat activated) call, another phone on the same line is picked up, the voltmeter will read 6-10 Volts, red LED L4 will go on and green LED L2 will go off. The same things will happen when a lineman's test set in the active mode is connected to your line. If your line is cut, the voltmeter will read 0 Volts.

7. After your call, just hang up and place S2 in the "down" position. You can leave S1 in the "up" position. See the last part of STEP 2 for further information.
8. You can make or receive a secure call by simply placing S1 and S2 in the "up" position, when you are ready to make a call, or when your phone rings, prior to picking up your phone.

Step 4 When, why and how to use the JAMMER function.

When your phone in ON-hook, various eavesdropping devices could be used to listen to your ROOM conversations, EVEN conversations in a room where there is no telephone!!
One of these devices is an infinity transmitter, explained above. Also used are hook switch bypasses, line drivers, etc. etc. All these devices can eavesdrop your ROOM conversations when your telephone is ON HOOK.

As you have read earlier, the Tap Nullifier will alert you to these types of devices, but you have to be there to WATCH the LEDS and the voltmeter.

To "JAM" such devices, just place switches S1 (SYS) and S3 (JAM) in their "up" positions after you hang up your phone. Green LEDs L1 and L3 will come on.
All the eavesdropper will hear is a loud "HISS". Just pick up the phone to verify that the JAMMER is operational....

OF COURSE:

You need to turn the JAM function off before making or receiving a call.
You need to turn the JAM function off if someone in another room needs to make a call on the same line that the Tap Nullifier protects.
You need to turn the JAM function off if you expect a call on your answering machine.

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