Timed Signal From The Cable Line example essay topic

On Wednesday, the 13th of March 1991, American Cablevision of Queens, New York, sent the first electronic 'Bullet'. This so-called 'Bullet' was in fact, an electronic signal directed to unauthorized cable boxes causing them to turn-off. Approximately 300+ unsuspecting customers then called the cable company to complain and were subsequently taken to court for cable theft. The 'Bullet' works by ordering the computer processor within the cable box to lock-up if it is authorized for all channels. Since pirate chips installed in a cable box would authorize all channels, the TV 'goes black'. HOW THE CABLE COMPANIES CATCH PIRATES There are several methods; here are some of the more popular.

The first method is somewhat costly to the cable company, and is used usually only when they think they have a thief. A device called a Time-DomainReflectometer (TDR) is used to send a timed signal from the cable line outside you home to your decoder. The reflected energy of the signal is measured and then compared to previous measurements to find a time difference which would indicate that the box has been tampered with. Pirates were able to get around this by installing an in-line amplifier which would weaken the reflected signal. One problem with TDR is that you need previous readings, which are not usually taken at the time of installation for a reference point. The second way is to modulate an identification signal onto the cable line at about 108 MHz.

This signal sounds something like a 'cuckoo', and 'leaks " from the converter box where it can be picked up by cable company employees outside of suspected pirates homes using hand held receivers. Unfortunately the signals sent by the cable companies can also cause interference with FM reception within the home. A third method is to program all cable boxes from the head end to display a message. This message is displayed only by boxes which have had a test chip installed and left in.

The message informs the customer that they have won a free t-shirt or something similar. They only have to go to the Cable Company HQ to pick up their prize. And what a prize it is! A FREE trip to jail!

Don't fall for this. There is no free lunch. IS THERE A FIX FOR THE BULLET? Yes, there are several solutions to the problem.

The 'Bullet' as sent causes the box to lock-up, and not output a picture. The fix is simple - unplug the power cord. After a few minutes, plug-in the box again and it should reset. At worst, the box may stay dead for up to 24 hours.

Ift his doesn't work - go to the next fix. The second fix is to install an in-line trap to filter out the actual message or 'Bullet' before it can get to the microprocessor. This is accomplished by inserting on the cable going to the box, a small F-M trap. This trap is designed to 'filter' out the frequency carrying the 'Bullet " information. Unfortunately, there are a few side effects. One is that the box will not be updated with time-of-day, special messages and other " housekeeping' instructions.

These small traps are popularly referred to as " Bullet Busters'. The third fix is to go inside the box, locate the small, usually RG-174 Mini-coax cable carrying the demodulated F-M information and cut this cable. This has the same effect as installing a trap but costs nothing. Ofcourse, if the box belongs to the cable company going inside the box is not advised. You may, however, purchase you own cable box. BUILDING THE CIRCUIT Addressable cable systems use a data channel to address or 'instruct' the cable de scrambler as to which channels you are authorized to watch.

Typically this is done by modulating control data at 106.5 MHz. This is not the same as the 'cuckoo's o und which is typically sent at 108 MHz. To see if you have the either of the modulated signals present, simply attach a FM radio to the cable using a suitable splitter / adapter Scan the band around 106 to 108 MHz listening for beeping noises. If noise or interference is located, the 'Bullet Buster' will usually eliminate it once installed. The 'Bullet Buster' is a passive band-rejection or notch filter configured as a type-T trap.

The filter gives about 40 to 60 dB of attenuation using only one resonant circuit. Tuning is accomplished by turning a small trimmer capacitor to set the frequency, while a trim potentiometer permits critical adjustment of notch depth. The entire circuit can be built on a small piece of PC material. Mount the in / out jacks first and the pot, trimmer and finally the rest of the parts. To adjust, turn C 2 for frequency and R 1 for notch depth until interference is blocked from reception into your FM radio receiver. Once adjusted, remove and reinstall into the cable line just before the decoder / de scrambler.

Plans for the BULLET BUSTER are in the CABLE HACKERS BIBLE Volume 2. Finished units are available for $15.00 to $25.00 from other various vendors. We do not sell them. Check the back of any issue of ELECTRONICS NOW magazine (available from newsstands everywhere). Although the 'Bullet Buster' will eliminate the interference signal, it will also eliminate all programming instructions from reaching the set.

This means that if you order a PPV program with the filter still in-line, the box will NOT accept the instruction, and of course, you will NOT be able to see what you " ve paid for. If, after installing the trap, the converter shuts down, unplug the filter for a while to allow the converters microprocessor to update. Alternatively, try unplugging the power and then plugging in again forcing a computer reset condition within the converter. Do not use the 'BulletBuster' to circumvent the cable companies right to de-authorize the converter, or in any other unlawful manner.