Introduction
Today I’m bringing you the disassembly, teardown, and analysis of a vintage Nokia d-box Multimedia Terminal (DVB) — a relic from the early days of digital broadcasting. This Nokia d-box receiver teardown will reveal the inner workings of this classic device.
Background
Back in the day, these pay-per-view terminals were everywhere. Satellite and cable TV were at their peak, and streaming platforms like Netflix or Disney+ didn’t even exist yet. If you wanted premium content, you needed one of these boxes — often provided by your cable company — and a subscription card.
Teardown
When I first tried to open the unit, I noticed it used security Torx screws on the top cover. I didn’t have the right bit at the moment, so I took it home to try again.
Later, I realized it wasn’t Torx at all — it was some kind of pentalobe security screw, the kind you rarely see outside of Apple devices. My iFixit kit didn’t include that bit either, so I had to resort to an extraordinary method to remove the cover. Let’s just say it wasn’t elegant, but it worked.
Security screw found in the Nokia d-box satellite receiver
The Nokia d-box DV3 is surprisingly well-built for a consumer-grade multimedia terminal. It features a plastic bottom shell where the main PCB is mounted, a metal top cover, a separate front panel, and a metal shield on the rear. Inside, there’s also a metal internal frame that adds rigidity and structural integrity once the unit is fully assembled.
To disassemble it, you’ll need a special pentalobe security screwdriver — not something you’ll find in a standard toolkit. Using special screws was a common method of the era, and similar solutions were found in other vintage satellite and cable receivers. These anti-tampering designs were intended to prevent manipulation and piracy, especially in pay-per-view systems, where protecting access to premium content was a priority.
Main Board and Architecture
Let’s get into detail! What I was excited about those vintage receivers of the late 90’s is that they were very expensive so probably they would have a lot of electronic components is to see what kind of integrated circuits inside, memories, microcontrollers, maybe even an FPGA?
The receiver features a single main board with all elements integrated on it (Power Supply, receiver and modem), except the control panel display, which is a commercial unit from Hyundai.
Power supply
The Nokia d-box DV3 uses a switching power supply, integrated directly into the main board. Although it’s part of the PCB, it’s clearly isolated by clearance zones and marked with warning signs printed on the board — likely to prevent technicians from touching the area while the unit is powered.
One of the key components is the L4940D2T5, a 5V linear voltage regulator. It supplies power to the digital logic circuitry, but it’s likely that other parts — such as the display, modem, or RF receiver — require additional voltages.
Interestingly, I couldn’t locate a dedicated PWM controller IC, which is unusual. A switching power supply typically relies on a PWM chip to regulate voltage efficiently. It’s possible that the PWM functionality is embedded in another component or handled by a custom ASIC, but it’s definitely something worth investigating further.
Satellite Receiver
Separate module, connected. Shielded to prevent
Modem
Strangely, the receiver has a modem module, based in the chip
Main Board
The mainboard is marked 5511985-03A in the copper and 55 11985-03 with silkscreen both in top and bottom sides,
PCB Technology
The main board is a 4 layer stack with standard 1,6mm thickness, as usual. It features mostly SMD components, having components on both sides of the board. Components placed in the bottom (solder side) were soldered by solder wave (not selective) the smaller components being 0805 packaging (fortunately).
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The manufacturing process is: Pick and place places all of the components in the top after solder paste using a stencil, after that IR reflow ovens, that attach the components to the top side of the board. After reflow process has been completed, pick and place to components in the bottom, which are attached to the substrate by means of adhesive (red loctite), then it is flipped and the Thru Hole components are inserted and the bottom components and THT components are soldered in a solder wave.
The first time I knew I was surprised that SMD components can be soldered by wave, but yes, indeed they are, although care has to be taken in the design and soldered components have to be placed in certain direction (sometimes using solder thief pads)
Display
The display is manufactured by Hyundai, marked as HT12538-D on the PCB and HT12538FB-LYPF-04, which is likely an assembly or batch number. I haven’t seen the display working yet, since I haven’t powered up the receiver. However, it appears to be an LCD dot matrix display. Searching those part numbers only returns results related to the d-box itself, which suggests that the display was manufactured specifically for this device.
Close picture of the display. Source
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