Nebula Electronics
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For the Eastern European satellite television provider named Digi TV, see Digi TV.
Nebula Electronics Ltd were 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 Finland, France, Italy, Germany, Spain, and Sweden. 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, saturated menus. It can be controlled either by the mouse, keyboard or remote control.
There have been 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.
Nebula allow potential customers to sample their software before buying the hardware. In 2006 the DigiTV software was opened up to non-Nebula Digital Terrestrial cards supporting the BDA standard but a license has to be purchased to continue using for longer than 2 minute periods. The emergence of free, competing software, such as Mediaportal, Webscheduler and mythtv (to name just a few) have greatly reduced its attractiveness. Head to DVB owners forums for more software. DigiTV's multicast/unicast feature (which was greatly touted upon initial release) never worked correctly for rev1 pci cards, and was never addressed.
The drivers that ship with the DigiTV cards do not support the BDA standard used by Windows Media Center and many other 3rd party software but a few developers have added direct support for Nebula's drivers (ShowShifter DVB and TSReader being two examples).
Nowadays they have slipped behind the cutting edge, Vista is barely supported, software fixes only occur every half a year or so, and a working version 4 will not be free to its existing customers. Version 3 is prone to a fair amount of crashes on a great range of hardware.
External user forums on the DigiTV software even proclaim to fix the problems first rather than adding new, useless stuff to the buggy software.
Nebula Electronics were once one of the pioneers for DVB-t cards, but have since been overtaken by larger competitors with better software and hardware development.
In December 2007 liquidators were appointed to wind up the company .London Gazette - Official Notice
[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. Tuner Sensitivity in the original rev 1 card is very low and quite susceptible to PC power supply rail noise, and to radiated noise inside the PC case.
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. [1]
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. On the USB Master unit 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.
