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22 I Am An Electronic Technician, Where Can I Get The Plans To Build ADescrambler So I Don'T Have To Pay To Watch Scrambled Channels?


This article is from the Satellite TV FAQ, by Gary Bourgois flash@lopez.marquette.mi.us with numerous contributions by others.

22 I Am An Electronic Technician, Where Can I Get The Plans To Build ADescrambler So I Don'T Have To Pay To Watch Scrambled Channels?


Where Can I Buy A Decoder So I Can Watch All The Pay Channels For Free?

You would be amazed at how many times we receive this question,
usually in EMAIL. Most people who are not familiar with how
scrambling works, wrongly assume it is some kind of a hardware
circuit that can be constructed with components from the local
Radio Shack. BZZZZZZZZT wrong answer.

The present system used in the USA, and by most of the more secure
video channels in Europe and elsewhere on the planet use a far more
sophisticated system, one that is "addressable". The current system
employs what is called "sound in sync". The audio portion of the
program is encoded as little winky dots hidden in the sync pulses (the
bars on the top or side of the screen that you do not normally see
except when your set is misadjusted. This digital encoding also allows
them to say "DIGITAL SOUND" a nice buzzword. The audio is a compandered
15 bit system. Some with "golden ears" find the sound raspy, but most
folks can not tell the difference.

The real reason the sound is digital is NOT to provide sound quality, but
rather to insure that unauthorized reception is not all that easy, and
a decoder can not be built from scratch.

The scrambling system uses a dual decryption key system, and is based
on the USA DES encryption standard (this is a military sensitive system,
making export of VCII type decoders illegal).

The scrambling method consists of:

1. The authorization center (in California) which creates the
master datastream. This datastream contains a digitally derived
key based upon the serial number of EACH authorized decoder and
a "Tier bit" for EACH channel it is authorized to receive
(determined by PAYING for the service)

2. "SEED KEYS" in the receiver itself which are COMBINED with
the other half of the key (transmitted by the authorization
center) to then create the master key used to decode the audio
and turn on the video descrambling circuit (The VIDEO is a
simple matter to decode, as it is only video inversion and
sync suppression).

But WAIT! What about these pirated decoders that one can buy for about
$1000 that claim to give you all the channels free? Didn't some electronic
genius BUILD them?

No. What the pirates did was to create "clones" of the chips in one legal
decoder that they paid to have authorized. They then removed the chips from
other legally purchased decoder boards, and put their "pirate chips" in their
place. The result is that whatever the master parent box sees, so does all
it's clone child boxes.

The rub here is that:

1. The pirates, after making a few million dollars in sales from their
clones, moved to the Caribbean, out of USA law. At this time they
also stopped paying for the subscription on their ONE legal decoder
from whence all the clones are derived. POOF. All the clones go

2. Other pirates, not as smart get caught by the FBI. The FBI turns
the serial numbers over to the authorization center. POOF. Same
scenario. All the clones go dead.

3. Some pirates were not caught. Some clones still live. HOWEVER,
G.I. (the company who makes the decoders) CHANGES the scrambling
system this fall to a totally new method. POOF. Etc.

Cloning is the main method of pirating the signals. No one has EVER built a
VIDEOCIPHER descrambler from scratch. The very technology employed requires
that the system co operate with the authorization codes transmitted along
with the TV signal. There is no hardware way around this. It is a software
scramble, requiring TWO halves of the code.

There is a second method of descrambling, which involves entering the other
half of the key MANUALLY with the keyboard. This is called "WIZARD"
Technology. However since the code changes every month, a new WIZARD Code
must be entered. To obtain these codes, some pirates set up 900 type phone
numbers. The FBI then gets a printout of everyone who calls. POOF.

Recently, the programmers have taken to a new tactic to foil the
wizard code users. Instead of monthly changes, they started changing the
codes every three days or so. There was an unhappy side effect of some
LEGAL users and Cable Companies also losing their authorization, but we
can expect these tactics, called ECM, or Electronic Counter Measures to
continue. We understand that this methodology HAS been successful in
discouraging some of the die hard pirates, finally convincing them to
get legal boxes.

Since HBO and Showtime finally dumpped the VC2 commercial Datastream in
October of 1993, pirate boxes just plain no longer work.

An older hack that no longer works was called the THREE MUSKETEER HACK. (All
for one and one for all). If a person subscribed to ONE channel, the
modified decoder chip then descrambled them ALL. This one died a LONG time

GI Turned off all the old 032 boxes with an ECM (Electronic Counter
Measure) on March 15, 1993.

The VCII Decoders no longer work. If you want to receive scrambled
programming, you need a VCII+. All LEGAL subscribers were supposed to
receive free upgrades. Those with pirated decoders could not upgrade, and
lost their investment. The VCII+ RS (Renewable Security) decoders have
already been delivered, one step of security above the VCII+. The RS has a
little slot for a "smartcard" which will be sent to legal subscribers when
the pirates break the VCII+ code. And DIGICIPHER decoders are already coming
on the market, which will be the NEXT kind of decoder on the market AFTER the
VCII+ RS. You can't keep up with it if you don't have a legal subscription.

Scrambling is a fact of life. It is not going to go away. There are three
ways to play:

1. Pay for your subscription. In the end this is the cheapest way to
go if you MUST watch the couch potato type programming offered on
scrambled channels. Your $1000 pirate decoder can (and will) go
dead on you, with NO recourse.

2. Just say NO to descrambling and watch the HUNDREDS of free and more
interesting signals available. Listen to the free audio services.
Save LOTS of money.

3. Don't listen to what I have said and find a pirate decoder. Enjoy
it while it lasts, and hope that the FBI does not visit you.

PIRACY is a crime in the USA and in other countries. Pirates are caught,
fined and in some cases jailed. The justification for this is that the
scrambled signals are the property of the PROGRAMMERS. If you watch without
paying you are stealing. Some people try and justify piracy by saying the
signal comes on their property uninvited. This argument, while it sounds
good does not hold up in court.

Scrambling remains a HOT issue in the industry. Publications exist in the US
and elsewhere with news of various methods pirates use to steal programming.
You can join this underground if you want to. Or you can purchase a legal
decoder, and hope that they continue to provide free upgrades with EACH change
in the scrambling technology (there are THREE more changes already known to be
coming to the USA scrambling scene).

However now at least you know. You can't go to Radio Shack and get the parts
to make a descrambler for $15. It is NOT that kind of a system.


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