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4DTV Glossary:


Options 605 - This is shorthand for a sequence of key presses on the 4DTV remote. There are key sequences that do not necessarily correspond to on-screen menus. Options 6778 is another. While you can see most on-screen displays change when in the options menu, there is no option for 0 or 7 listed on the sceen but it is there.
To do an option 605:
a)press option (options menu appears)
b)press 6 (6 is a listed menu choice )
c)press 0 (not listed)
d)press 5 (menu choice)
You will now be at the diagnostic screens, that tell you, rather tersely, what the receiver is thinking. See also the 4DTV FAQ for advanced users.

CF@G7 - That means move the Dish to G7 and program the Generic satellite CF at the same position. The 4DTV can have 1 satellite or all of them programmed at the same position, The usual designation is Generc@Normalsat . To do this:
a) Move the dish to G7
b)Press Options 644 then [enter]
c)use the arrows to highlight CF
d)press [enter]
e)adjust as needed
f)press [go back]
g)press [enter]
h)press view, select channel
Why would you want to do this? See the forum's fabulous Owners Only section.

LNB - Low Noise Block - a device hooked to a satellite dish's feedhorn that receives the signal at ~4 or 12 Ghz and converts it to a lower frequency for input into a receiver.  

LNBF - Low Noise Block and Feedhorn -  an integrated LNB and feedhorn. Commonly, LNBFs are 1 piece and most have no moving parts, where a sperate feedhorn will have a polarity motor on top for non-circular feeds. 


Rotate LNB - this means get out a wrench, ladder, pliers, screwdriver and... j/k. It refers to deliberately mis-programming the skew to receive a channel at a given frequency but opposite of the programmed polarity. If you needed to "Rotate LNB" for some reason, you would:
a) go to the proper satellite
b) Press options 644 [enter]
c) arrow down to the skew adjustment
d) Change the setting: for instance, if your vertical polarity is normally 90 and your horizontal polarity is normally 0, you would progam the V to read 0 and the H to read 90.
e)Use the channel up/down buttons to select a channel that will allow the other skew value to be changed as well.
f)when the skew for the satellite is good and backwards, press [go back]
g) press [enter]
h) press [view]

Polarity - The orientation of the satellite signal, usually relative to the dish. There are 4 polarities:

Skew - an incremental polarity adjustment, necessary to "fine tune" polarity since not all satellites are perfectly oriented and no dish has perfect tracking. 


IPG - interactive program guide. Love it or hate it, you miss it when it's gone....


Channel Maps - The pre-defined set of instructions given to the receiver to be able to tune a given channel. The channel maps tell the receiver the channel recipe for any given channel including the following parameters:

The channel maps are transmitted via any DCII service, but only certain channels (like G0-300) contain maps are compatible with the 4DTV. Some Units require a power reset in order to get updated maps.


VCN - Virtual Channel Number. Virtual Channels appear as extra channels above the normal channels on a given satellite. A Virtual Channel would be something such as channel 612 on C3 (Discovery Science Channel) It is actually on transponder 22 but since there are 9 other channels on that transponder, it was easiest for all to just tune a channel number. The mini dishes also work on this principle.

Analog - a standard FM video signal

DCII - Digicipher 2 - a digital, proprietary, transmission system developed by G.I.

VCII - Videocipher 2 - an analog scrambling method developed by G.I.

VCRS - Videocipher Renewable Security - The successor to the VCII module after the latter was hacked by all in the 80's.

GI-Dunno - name given to any 4DTV bug

Damien - the Delphi bug that causes posts to not appear or the find function to not work at all. See also: ODBC error.

DVB - A digital format developed by everyone else. The 4DTV cannot receive DVB format.

Sidecar - A receiver that functions in addition to your existing receiver. A sidecar is a receiver but usually does not control/position the dish or polarity/skew, more like a cable box that tunes satellite channels. Also called a slave receiver.

I.F. - Intermediate Frequency - most modern Satellite receivers do not directly tune satellite downlink frequencies. Instead they tune an image frequency known as an Intermediate Frequency. The 4DTV, the Pansat 200a, All DSS and Dish Receivers tune to an Intermediate Frequency between 950Mhz and 2150Mhz for any selected signal, based on downlink frequency. There are many reasons for this, 1 being that it is easier to manage a 1Ghz signal than a 4 or 12 Ghz signal. What you tune to is a function of good old Math. The LNB has a local oscillator (a miniature frequency generator) inside it so that the combiantion of the internal frequency and the actual frequency produces an image frequency. That is the way the 4DTV  reads out it's frequencies on DIAG. C.

For C-band, an American LNB generates a frequency of 5,150 Mhz

For traditional Ku, an American LNB generates a frequency of 10,750Mhz.  

For DSS/Dish/Expressview the LNBF generates a frequency of 11,250Mhz.

the receiver tunes the corresponding I.F. The math is simple subtraction: 

To tune a C-band frequency (for example 4,120Mhz) altered by it's journey through an LNB, the math would be:

5150(internal LNB frequency) - 4120(actual frequency) = 1030Mhz(I.F.). 

Conversely, to extrapolate the Actual frequency from an I.F. reading, the math would be:

5150(internal LNB frequency) - 1030(I.F.) = 4120Mhz (actual frequency)

Ku works in the opposite way as C-band: To tune a Ku-band frequency (for example 11,760Mhz) altered by it's journey through an LNB, the math        would be:

11760(actual frequency) - 10750(internal LNB frequency)   = 1010Mhz(I.F.). 

Conversely, to extrapolate the Actual frequency from an I.F. reading, the math would be:

10750(internal LNB frequency) + 1010(I.F.) = 11760Mhz (actual frequency)

 

 

MCPC - Multiple Channels Per digital data Carrier. MCPC DCII is the only kind of digital carrier the 4DTV can tune. For Example: Discovery Science Channel is on Virtual Channel 612 on Satcom-C3. The actual transponder is transponder 22. There is one digital data stream on transponder 22, but that stream is divided into 9 data sets which are rendered as 9 channels.

SCPC - Single Channel Per digital data Carrier. A digital carrier that has only 1 channel on it. PBS has some affiliates with Single-channel carriers in the sky.

GSOD - Grey Screen Of Death - The grey screen of death is when the unit displays a "This channel is not available." screen. Most common with un-mapped DCII channels. These channels may not be subscribed to as they are not configured for 4DTV authorization. Some channels may show a "Not Subscribed" message similar to Classic Sports on XB-400 . 



Please wait - We are processing your request - This message shows up for 2 reasons: 1)the autorization status is missing from the data stream, or 2)you have tuned to a DCII channel but there is no longer any signal there. Small consolation, AT&T Digital Cable customers also get this message when the DCII AT&T Digital Cable signal is too low for that Digital Channel. AT&T Digital Cable boxes are DCII and 2nd or 3rd cousins to the 4DTV.

DSR-920 - A 4DTV receiver.

DSR-921 - A 4DTV for Canada, it does not get all DCII channels that a 920 gets and cannot be subscribed to American programming such as HBO Digital or STARZ Digital. Converesely a DSR-921 can be fully subscribed to Star Choice, a 920 cannot.

DSR-922 - A new version of the 920.

Manual Tuning - Something the 4DTV will probably never have. Manual tuning would allow you to set all tuning parameters for a signal. Currently the receiver is limited to whatever is in the channel maps, hence the need for generics to tune in missed channels.

AUTO Search - Something that works for about 5 minutes after a Master Reset. Auto Search allows the 4DTV to find a DCII signal when the parameters are not the same as the currently tuned channel.

SR - Symbol Rate. A measure of the speed or bandwidth of the digital DCII or DVB data carrier. All 4DTVs can do 2 Symbol Rates: 19.51 Mega Symbols per second and 29.27 Mega Symbols per second. The DSR-905, 922, 4400 and 4800 can do lower symbol rates, down to around 3 Mega Symbols per second. Many folks use bitrate and symbol rate interchangably, although they are not exactly the same. The Pansat 200A refers to SR in the tuning screen, yet it defines SR in terms of Khz.

Power Reset - Method of Resetting the 4DTV simply by pulling the AC plug and then plugging it back in so as to cause the unit to reboot. Some folks think it takes 30 seconds or 30 minutes It only needs to be long enough that the unit notices. You are successful if the unit reads WM UP when you plug it back in. Unlike a Master Reset, all settings are preserved.

Master Reset - A complete reset of the unit, almost back to original outof the box condition. All settings, updated channel maps, timers, satellite settings, favorites lists, custom audio settings, Provider I.D., and Vice-Presidential Emails will be erased during the reset. Click here for complete Master Reset instructions

Provider I.D. - A Digital Identification number unique to each programming vendor that is transmitted to your unit via satellite by whomever you can get to send one to you. Some programmers want you to buy something before they will give you one, others, like Superstar, will send you one free, but you may get a call later from them trying to sell you a DiSH Network System. All Digicipher-II products require a sponsor or Provider I.D. to work at all. This means that you have to marry a Provider and get them to sponsor your unit before you can decode ANY DC-II signals, even the free ones like DMX, GAC or the Infomercials. To get one for the first time, call your programmer or Superstar and tell them you have a 4DTV that needs to be authorized. They will ask you for the numbers of your unit and name/street address/etc. if you don't already have an account with them. They can then send you Direct Mail about how great it is to get a DiSH Network 500 system. Hold out for a DishPlayer though ;)

Rehit - A transmission of "administrative" digital information to your 4DTV. This may include, but not be limited to: Time Zone (G.I. feels you are too stupid to set your own clock, but the Providers barely do it right anyway, expect your clock to change timezones any time you alter your digital programming package, or for no reason at all), Location, Provider I.D., Authorized Channels.

Generics - Satellites in the 4DTV's Memory that can be used in positions where there is no satellite defined or in place of a "normal" satellite that has deficient channel maps.

Root Transponder - The actual frequency of a virtual channel multiplex. Discovery Science Channel (C3-612) has a Root Transponder of 22. You can see the Root Transponder of any Channel over 100 on any satellite by going to Diagnostics G. (see also options 605)

AOR - Atlantic Ocean Region - Used in regards to satellites east of SBS6 @ 74deg West

POR - Pacific Ocean Region - Used in regards to satellites west of Satcom C5 @ 139deg West

Transponder - A frequency repeater that receives a  signal or collection of signals  and sends out the same thing on a different frequency set.

DSR 905 - A receiver that functions along side your present analog receiver to add DCII reception.
The DSR does not move the dish but will control polarity.

BitStream - The actual data stream. Rod Hewitt's Technical dissertation follows. 

from:  Rod Hewitt (RODHEWITT) 
To:  1notmike (NTDWS)
If I may, a little more technical info.

DCII (like DVB and DSS) uses QPSK modulation which results in two bits being sent per time period. When these are recovered by the receiver, there are two lines coming from the front end, the I and Q components.

In some DCII formats (and all DVB), the I and Q bits are shifted into parallel in order, i.e. they are combined so that their order in a byte is IQIQIQIQ.

Some DCII formats split the I & Q into two different transport streams so that the reconstructed bytes are IIIIIIII or QQQQQQQQ. This was apparently done because DCII has been around for a long time and I would imagine that some component in the DCII system couldn't handle the data rate of combining the two phases and so they split the stream into two, halfing the bitrate.

In split mode, there really are two transport streams - each with its own PAT/PMT plus the DCII extensions like the VCT and TDT. These DCII extensions are what's responsible for tying the two transport streams from each of the phases together so that they appear to be one set of channels.

Needless to say, GI has gotten around the problem since there are now QPSK carriers running 29.27Msps in combined mode.

A little correction on your bitrate math:

29.27MSps = 58.54Mbps (b = bit, B = byte)
58.54Mbps * (188/204) = 53.94Mbps (this is the Reed-Solomon coding overhead)
53.94Mbps * 0.75 = 40.46Mbps (3/4 FEC coding overhead)
40.46Mbps / 8 = 5.05MBps (not that Bytes really matter in the communications world - everything is though of in bits)

Regards,
Rod

Megapipe - A method of DCII transmission that requires the use of a DSR-4800. In Megapipe, a DCII datastream is transmitted at only 29MS/s but in combined mode..

DSR-4800 - A receiver from GI that can do just about everything, including DVB, DCII, and Megapipe. Good luck getting it authorized by any pay DCII services though.