Nebula Electronics

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Nebula Electronics Ltd are a small UK company specialising in digital terrestrial cards for Windows PCs. The brand-name for their cards is DigiTV.

Many users recommended the DigiTV cards due to their easy-to-use software, which was very similar to set top boxes. The installation routine is also very simple, especially for the USB models, which do not require opening up the PC.

Nebula operates entirely from the United Kingdom, including production and direct sales but they also have distributors in Australia. They are renowned for offering the majority of features for the Freeview service including Audio description and MHEG-5, something that competing products do not.

[edit] Software Details

Part of the reason that Nebula's software differs so much from the competition is that they built it completely from the ground up, without using DirectShow. The benefit of this is that their software isn't affected by other DirectShow filters installed on the system (such as those from 'codec packs') but it has the downside of not allowing certain graphics card hardware acceleration features, which are usually accessed through DXVA.

The DigiTV software (renamed iTuner in the next release) has a set-top box feel to it, with large fonts and bright, colourful menus. It can be controlled either by the mouse, keyboard or remote control.

Nebula are unique in that they allow potential customers to download and try their software before buying the hardware. The software will not be fully functional (and does not work with competing DVB-t cards) but does give a feel for the software, and also allows the prospective purchaser to see whether performance will be satisfactory on your system. [1]

There are frequent updates to the software which bring enhancements, bug fixes and new features. One of the more recent updates allows the use of multiple DigiTV cards to record multiple channels, and also the ability to record several channels from a single multiplex with just one card. In the UK for example, all of the ITV and C4 channels are located on Mux 2, and so it is possible to record ITV1, ITV2, Channel 4 and E4 at once, all with just one card.

User forums on the DigiTV software frequently bewail the company's habit of adding more functionality with each release, rather than fixing all the bugs in the previous release(s).

The drivers that ship with the DigiTV cards do not support the BDA standard used by Windows Media Center or many other 3rd party software (although they have recently released beta BDA drivers for the DigiTV PCI) but a few developers have added direct support for Nebula's drivers (ShowShifter DVB and TSReader being two examples).

Now days they have excellent support in nordic countries, foremost in finland

[edit] Hardware Details

DigiTV PCI (Rev 1)

• DVB Demod/Decoder: ATI/NxtWave NXT6000
• PCI Interface: Conexant Fusion 878A
• Tuner: Alps TDED4 DVB-T
• Remote: One-4-All Remote or Nebula Remote

Nebula designed their own card using the NxtWave NXT6000 DVB-t demodulator and an Alps tuner, the same as the popular Setpal-branded Freeview boxes. PCI interface was taken care of by the Conexant Fusion 878A chipset, which also handled analogue video input.

DigiTV USB

• DVB Demod: ATI/NxtWave NXT6000
• USB Interface: Cypress FX2
• Tuner: Alps TDED4 DVB-T
• Remote: One-4-All Remote

Launched with the DigiTV PCI, the DigiTV USB was an external box that connects via USB 2.0. While it didn't have the analogue capture of the PCI card it did have an integral USB hub.

Master DigiTV-PCI (Rev 2)

• DVB Demod/Decoder: Zarlink MT352
• PCI Interface: Conexant Fusion 878A
• Tuner: Alps TDED4 DVB-T
• Remote: Nebula Remote

In 2005 Nebula replaced the original DigiTV PCI. The new design had a half-height PCB and replaced the NXT6000 with the Zarlink MT352. Functionality-wise the cards were the same although there are some minor differences. It is not possible to compare bit error rate, (BER, a measure of signal quality) figures between the old and new cards because they measure it at different stages. The NXT6000 calculates BER before Viterbi error correction. The MT352 calculates it after, and so gives lower apparent readings (usually 0.000). This gives the impression that the new card has a better tuner and reception quality, which may not necessarily be the case.

Master DigiTV-USB (Previously "µDigiTV")

• DVB Demod/Decoder: Zarlink MT352
• USB Interface: Unknown
• Tuner: Alps TDED4
• Remote: Nebula Remote

The tiny (115mm x 80mm x 28mm) µDigiTV (pronounced 'micro-DigiTV') replaced the original DigiTV USB in 2005, and differed in that it takes power from USB rather than a separate mains adapter, and doesn't have the USB hub built in. As with the MT352-based PCI card the µDigiTV gives low BER figures. On the back of the unit there is a USB Type B port, aerial in and aerial passthrough for daisychaining additional Slaves. The base of the unit has non-slip rubber feet, which is needed because of the units very low weight.

Slave DigiTV-USB

• DVB Demod/Decoder: Zarlink MT352
• USB Interface: Unknown
• Tuner: Alps TDED4
• Remote: None

In late 2005 Nebula began to offer a "slave" device which was essentially a low-cost additional tuner similar to the µDigiTV. The DigiTV PCI and µDigiTV became DigiTV Master PCI and DigiTV Master USB respectively, to differentiate from the DigiTV Slave USB unit. The "slave" requires a "master" device to operate. In terms of hardware there is little difference between the Master and Slave, apart from lack of an IR receiver on the Slave, and different firmware.

µDigiTV Master (DVB-S & DVB-S2)
In May 2006 Nebula are expected to release a USB unit capable of receiving Digital Satellite including the new DVB-S2 standard. [2]

Remote Control
The original DigiTV units were supplied with a universal One-4-All remote but this has since been replaced with a custom Nebula remote. On the PCI cards the remote receiver is a small box that connects to the card via a cable and mini-jack and on the USB units the remote receiver is built in.

Smartcard Reader
The smartcard reader connects to the PC via USB and allows the DigiTV software to decode encrypted channels (for example, Top-Up TV in the UK) with a suitable smartcard.

[edit] External links

• Nebula Electronics official web site
• Unofficial Nebula Support Forum
• Identifying Nebula DigiTV devices