Tag Archives: MPEG2

A look at the Nokia 9850T

The Nokia Mediamaster 9850T was one of the first ONdigital receivers released to the market, alongside the Philips and Pace models, and one of the first digital terrestrial receiver that Nokia had made.

Like other ONdigital boxes, the 9850T uses SECA Media-highway for its middleware, alongside the MediaGuard conditional access system. The box also has a PCMCIA slot for future digital interfaces, likely to enable upgrades. The front panel design is similar to the other models of the time, all boxes had a Power, Select, Menu and directional buttons to allow basic control of the receiver without a remote, and a 4 digit display which would show the channel number and the time in standby

Front View

Rear View

Lifting the Lid

Tuner Block

The tuner is implemented on a separate module away from the mainboard, it seems the board is based off the 9800/9700 satellite receiver, and when it came to adapting the design for the 9850T, Nokia added the DVB-T tuner module as a separate module. This module is soldered in and cannot be removed.

Motorola MC92314 Datasheet

The modem is also a separate component, connected what looks like an internal RS232 port, to the left you can see spaces reserved for the satellite tuner modules

Shot of the CPU and MPEG2 decoder, cannot find any other chips unless they are on the underside, so I assume this also contains the decoder.

Texas Instruments TMS320AV7110

From looking at the datasheet below, the CPU of the box is based on an ARM design and runs at 40.5MHz

Datasheet

Sony CXA20920 – AV encoder

Front panel display

Another shot of the main CPU and MPEG2 decoder, the Flash and RAM chips can be seen to the left side

The modem module itself

Size Comparison

Vs Pace Di4000

Vs Pace 2500S5

Conclusion

As this was one of the first DDT receivers on the market, the box seems to be quite primitive compared to the later Freeview receivers with its lack of a full EPG and more importantly 8K tuner support, however in the ONdigital era the Nokia was considered to be the more reliable and supported box (The Sony and Toshiba models did not get MHEG support) and there are reports of the 9850T being able to lock onto weaker signals better than its Philips or Pace counterpart.

The addition of the digital audio connecter would have been the main distinction from the other ONdigital boxes besides the Sony, since they were the only models to feature this.

Nokia would later go on to continue creating DTT receivers for the Freeview service, with models like the 221T or the 121T, which had an unorthodox and unique design compared to the traditional 9850T. Unfortunately Nokia exited the Freeview market after 2005, along with its satellite receivers and focused on mobile phones before Microsoft purchases their handset division. It’s not known it Nokia will reenter the set top box market.

A look at the Panasonic TU-DSB40

Panasonic were one of the major manufactures of Sky Digibox’s, and were considered to be one of the more reliable makes in terms of reliability and performance.

The front panel is typical of the average Sky box of the era, 4 led lights followed by 9 front panel buttons along with two card slots.

A loot at the system details screen, showing the software and revision information

Lifting the Lid

A very clean design, similar to the 2500S5

On the left you can see the main CPU and MPEG2 decoder, seems to be a custom Panasonic MN2 processor (MN2WS0002AD). Whilst I’ve not been able to find a lot of detail on it online, It’s a lot faster than the ST 5512 found in the Pace 2500S5

Not sure about the Panasonic chip towards the bottom, the MN7D022B3M, nothing much turns up online. Not much can be found with the Conexant chip either (SMARTSCM/336 CX88168-12) however one MAME driver source page has it down as a modem

Second card slot

Another view of the MN2 chip with the flash rom (bottom) and memory (Samsung chip next to the MN2)

Main central processor MN2WS0002AD, Looks like it’s missing a heatsink, or maybe Panasonic figured it didn’t need one. Most likely Sky winged about the price so Panasonic had to cut corners. Still the box feels cool to the touch when in use.

The front panel removed

Vs Pace 2500S5

Vs Pace Di4000N

Conclusion

The DSB40 comes from the same generation of digibox as my 2500S5, yet it feels so much faster in operation thanks to its processor. I’m not sure why Pace held onto the St5512 for so long when over digibox’s were moving onto more capable processors. Unfortunately I’m not able to find any further information regarding Panasonic’s MN2 chips that they used, only that they were used for Directv and OpenCable boxes also, and they were mostly MIPS based designed like the NEC EMMA used on some digibox’s.

Then again this box is running older software, maybe the later versions were more demanding?

The only major issue the the telephone cable connector, once you insert the wire, its suck to the digibox and cannot be removed without removing the back panel. I’m not sure why this is, if the connecter was mismatched for the case or maybe it was a cost saving design.