Acronyms Guide

This guide is something most projects forget, technical detail while needed to understand the scope and scale of abilities, is not easy to learn from the outside nor is common shorthand speak between new and current userbase members or the layman users who may stumble upon the project, we hope this guide provides some clarity.

Acronyms:

RF Tap & Tap Point

This is a BNC (bulkhead type) connector that's mounted to the back normally (if there is space) of a playback device, then a cable is routed going to a Video or HiFi audio test point or soldered to a point in the mainboard or amplification board with a full unprocessed modulated signal.

This allows reliable easy and permanent access to that signal, but can also allow you to add a composite on for example a SCART-only PAL player.

Note: Most current setups have a 10uf cap on the Video RF test points this allows real-time normal playback alongside, so you can get audio and standard video as a reference if needed, and can avoid the white spec effect which is signal losses.

Y+C, Luma+Chroma or Luminance/Chrominance

Luma = Light, Black & White Image information

Chroma = Colour, Coloring of Image information

Composite is combined Y+C 1 signal and 1 ground, S-Video has Y+C on 2 pairs of signal and ground wires.

Colour-Under Tape Formats

• JVC 1/2inch VHS, VHS-C, SVHS, SVHS-C

• Sony 1/2inch - U-Matic, U-Matic SP, Betamax, Super Beta, ED Beta, BetaCam, BetaCam SP,

• Sony 8mm - High8, Video8

• Philips 1/2inch - N1500, N1700, V2000

All use a “colour under” system of recording.

In this system, the luminance (B/W image information) is separated from the chroma (colour) information and sent to dedicated circuits to be processed.

The luminance signal is then used to FM modulate a carrier before it is recorded on the videotape, the chroma signal is then heterodyned with a local oscillator signal to down-convert the 3.58 MHz* frequency before being recorded onto the videotape.

Ranges slightly differ based on TV system & format.

Hence Luminance & Chrominance ends up as 2 separate .TBC files a digital S-Video.

Composite & S-Video

S-Video (4 pin 1 plastic orientation bit, shielded cable/connector) carry's video signals Luminance & Chrominance are kept separate Luminance is baseband like normal yellow RCA composite and chrominance is modulated to stop interference until the signal is physically received by the input device witch can then re-combine the signals to make a colour picture.

RF

Radio Frequency

In the context of this project, FM RF information is stored on the tape and transmitted via analogue electric signals over copper cable and or traces on the VCR'S PCB boards after being read by tiny magnetic heads in the head drum.

FM RF

Frequency Modulated Radio Frequency

This is the RF signal but the information is compressed via modulation onto carriers for transmission or storage like FM Radio or VHS tapes etc, formats like Video8/High8 use multiple modulated carriers to put video/hifi/timecode into one signal.

Baseband RF

This is an RF signal that has no modulation such as Linear audio that goes from a head to an pre-amp to speakers directly, or composite video that's meant to go directly to an analogue CRT television, or comes directly off an analogue camera.

MSPS

Million Samples Per Second, 2msps is = to 1mhz of effective information sampling of an analogue signal.

SNR

Signal to Noise Ratio, this is the ratio of usable signal to background or external noise or electromagnetic interference, for example, you want to keep phones/radios/wifi antennas and 120-240v power cables away from an RF line or connector that's not shielded.

You can tell what this is under ld-analyse with the Black SNR Analysis tab.

4fsc

Four times the frequency of sub-carrier, this is normally based on the composite signal standard for PAL/NTSC.

The 4fsc frequency sample rate is typically:

14.3 MHz (28.6 MSPS) in NTSC.

17.7 MHz (35.4 MSPS) in PAL.

In simple terms the same system used for D2/D3 tape.

DdD - DomesdayDuplicator

The 40msps (20mhz of bandwidth) USB 3.0 based RF capture device is purpose-built for LD-Decode but its filtering range covers the Colour Under Tape format ranges VHS/Beta/Video8/High8 and so on making it a very easy plug-and-play user experience on both Windows/Linux.

CX Card

These are referring to the Conexant CX2388x series of PCI chips (where x = 0-3), or the cards using them (PCI, or PCIE 1x via a bridge chip).

Warning: There is a later series (CX23884 - CX23889) that will not work as they use a whole new architecture.

CXADC

This is a modified driver that controls the CX Cards onboard hardware and allows a mode called RAW16 to output information directly instead of just digitising TV Signals and Composite ones.

.TBC & TBC File Format

This is the decoded output of, VHS-Decode (tapes), LD-Decode (LaserDisk) & CVBS-Decode (Composite).

There is 2 versions,

Composite which is 1 file, and Separated (like S-Video) which is 2 files, simple just like the physical cable equivalents only in the digital domain.

Tape is decoded to 2 files Chroma/Luma, this allows a lot more fine control.

Composite is just 1 file, Laserdisc is as well.

This is the lossless 4fsc decoded Luminance & Chrominance image data that's been demodulated and time base corrected.

Secondary Acronyms You Will Encounter

ADV

Analog Devices, Inc. chips of note, i.e. ADV7842 used by Blackmagic/AJA/Magewell in desktop cards USB cards and SDI equipment.

PEC Pads / Cleaning Pads

These are just lint-free same as generic high-quality wet wipes just dry and clean look-up nail wipes same stuff, you can get smaller "nail wipes" same exact thing.

There is also Suede (Pronounced ''Swayed'') cleaning sticks these are mostly a ripoff for camera sensor and VCR cleaning but are useful.

Storage Mediums HDD, SSHD, SSD, NVME.

There is 2 interfaces internally, SATA III and NVME,

HDD - Hard Disk Drive

Affectionately called spinning rust this is a plater of magnetic disks in an airtight helium-filled box they go upto 20TB in storage capacity in the 3.5-inch desktop sizing form factor.

1-2TB (7mm depth) (7200rpm) and 2-5TB (15mm depth) (5400rpm) in the laptop 2.5 inch form factor

HDD's are speed limited to around 200MB/s per drive at the 7200rpm spec.

Solid State Hard Drive

SSHD up to 4TB is an HDD with an 8-64GB solid-state buffer that caches data for quick use from writing data fast to storing files like small game data for quick loading, however, this adds a layer of reliability and recovery issues.

SSD - Solid State Drive,

It's used in your phone it's used in all modern storage, provides lower heat and high shock resistance, 1000x faster access times but less durable in some regards mostly in their read/write cycles and how much data they can move onto/off of is limited, so they dont die from operation hours they die from operating.

These got up to 100TB in the 3.5-inch desktop size using stacked boards, and 16TB in the 2.5-inch laptop size as far as consumers can get their hands on, 8-16TB is about it.

Hardware speed is limited to 550MB/s (SATA 6Gbps) per drive due to interface limitations.

NVME (Non-Volatile Memory Express)

Today becoming more commonly known as its being adopted in the "M.2 SSD" format NVME is a high-speed solid-state drive that directly connects to a system CPU (central processing unit) via PCIe lines which is how most secondary hardware is connected on computers such as video/graphics cards and HDMI/SDI capture cards and so on.

Due to the direct high bandwidth connection drives have gone in a few short years from 400MB's read and write directly to 2GB/s on the low end and 8GB/s on the higher end that's gigabyte per second not gigabits (Gbps) per second.

These are mainly used for Boot/Games and even camera recording drives for consumers and buffer/cache drives in more advanced use like storage servers.

Speed limited by storage hardware currently, 3GB/s Read and 2GB/s Write are common but can go up to 5GB/s Read & Write

In the near future, SD & CF cards will be replaced entirely by SD/CF Express as it's a faster more universally easier to implement in the mirrorless/cine market, CFexpress Type A/B and M.2 directly in caddies are taking over by storm.

Currently, the max capacities are the following

M.2 8TB

U.2 16TB (2.5 Inch) (SATA Sized Connector with Extra Pins)

Non-Volatile Optical Storage Mediums

DVD

One of the most common but now legacy optical media formats, today dye based disks are cheep as anything, and metal based disks are still available.

• DVD-R Single layer 4.7GB (4.37GiB)

• DVD-R Duel layer 8.5GB (7.95GiB)

There are some archival-grade disks that exist, but overall cost per GB it's more practical to go Blu-ray unless making legacy distros for testing or people are stuck on DVD.

Blu-Ray: BD & BDXL

BD or Blu-Ray Disks same physical size & mechanical operation as CD/DVD but a blue laser hence the name but the standard really means to the layman more storage per disk.

• BD-R Single layer 25GB (23.3GiB)

• BD-R-DL Dual layer 50GB (46.6GiB)

• BDXL-TL Triple layer 100GB (93.1GiB)

• BDXL Quadruple layer 128GB (119.2GiB)

There are also re-writable versions of note their usage in the Sony XDCAM cameras before the flash storage switchover.

• BD-RE Single layer RE-writeable 25 GB (23.3GiB)

• BD-RE Dual layer RE-writeable 50GB (46.6GiB)

These are used for SD/HD/UHD Video and Game delivery media today hence why all current-gen disk reading systems have a BDXL player.

M-Disk

The only consumer-affordable ISO/IEC 10995 rated archival media! (Currently)

Millennial Disc made by Millenniata (Fabricated and sold by Verbatim/Ritek today)

It's just a normal DVD/BD/BD-DL/BDXL-TL in terms of use with a bit of data saying "hey use higher power mode to burn" and are slightly slower to burn than standard disks using the 2x speed.

Using non-organic glassy carbon material that's neutral to temperature shifts and radiation instead of dyes and metals used on other media, its only weak point is the polycarbonate plastics which have a 1000+- year life the carbon holding the data could last longer M-Disk unlike normal discs have a high standard of validation for there plastics moulding and have perfectly smooth edges.

M-Disk only has 4 standard certified format versions.

• DVD-R Single layer 4.7GB (4.37GiB)

• BD-R Single layer 25GB (23.3GiB)

• BD-R-DL Dual layer 50GB (46.6GiB)

• BDXL-TL Triple layer 100GB (93.1GiB)

All Current DVD, BD, and BDXL burners support their respective M-Disk versions.

50GBP / 70USD per top-end BDXL reader/writers M-Disk wins in terms of future-proofing and cost of interface hardware with UDF disk formatting supported on all computer platforms from desktops and even IOS/Android based smartphones.

GlassMaserDisc

While being the most rugged optical media on the market in terms of stress tests at 1000 Euros for a 25GB or 50GB disc, they are fabricated on-demand primarily used for archive and master copies for duplication of release media.

The real-world value however is little, unless you have endless money these are just not as cost practical as M-Discs or Sony Optical Archive for small or large-scale archival due to the 50GB limit compared to 100GB/5.5TB.

Sony Optical Archive

Sony has there own in-house version of M-Disk starting from 2006 to today with there translucent high-density duel sided write once disks, this scales from desktop units to rackmount scale PetaSite system with automated loading and unloading of cartridges providing a full-scale optical version of LTO, meant primarily for permanent offline or recovery backup storage as they can't be overwritten by software and require mechanical destruction to be erased, water chemical and electronic interference cant damage this format in most real-world disaster situations.

Using a platter of 12 disks in a cartridge at 200USD per 5.5TB is very cost-effective for large archives i.e 100+ 3-6 hour tapes, but at a cost of 4000-5000USD for the desktop reader/writer units these have a high entry adoption cost, the software suite is free and self-contained for Linux/macOS/Windows but not open source however, disks do use the UDF (Universal Disk Format) system so can be read easily later on rated for a 50-100+ year shelf life.

LTO Linear Tape-Open

Current datacentres, broadcast groups, and small to large businesses will most likely have LTO tape for backup and or long-term archival, like with Sony's system this scales from desktop units to rackmount scale units with automated loading systems, meant primarily for long-term offline or on-site backup recovery storage.

As it's in the name these use high partial density magnetic tape, with current data storage encoding methods and physical manufacturing methods, sadly these are still very susceptible to high electromagnetic radiation but more so heat and moisture alongside mechanical ware and like videotape, these won't last long in high temperatures or survive floods but they are good for 20-35 years of shelf life.

Currently, we are on Generation 9 (LTO9)

18TB RAW / 45TB Compressed per cartridge at 150-220USD

Current, LTO8 and newer readers are still 3000USD or more LTO6-7 readers can be had for 100's if not under 1000USD on average via the used market.