2003.09_Fanless-Build Your Own Silent Digital Video Recorder.pdf

COVER STORY

Fanless Video Recorder

Quiet Please!

Multimedia is becoming more and more part of everyday computing. But the

noise produced by today’s systems is the biggest obstacle to living room PC

use. This article describes the hardware required to build a silent Linux video

recorder. BY DANIEL COOPER AND THOMAS KOCH

at current computer systems: one or

two power supply fans, and addi-

tional fans for the CPU, the motherboard

chipset and the graphics adapter, even

the hard disk needs cooling and just for

good measure let’s add an extra case fan

to really cool things down. A state-of-

the-art computer with a 2.5 GHz

processor converts about 100 to 200

Watts of energy to heat, and the noise

level grows alarmingly with each fan you

add.

compatible C3 processor. Both the moth-

erboard and the processor can make do

with passive cooling at clock speeds of

up to 600 MHz. We opted for the

ME6000P at around 130 Euro from [2].

The ITX form factor motherboard has

an extremely small 17 x 17 cm footprint,

and more or less constitutes a single

board computer as it includes a full set

of interfaces besides the CPU, the chipset

and the graphics adapter, sporting a PCI

slot, two IDE channels, a floppy connec-

tor, network, sound, TV output, 4 x USB

2.0, 2 x Firewire, 2 x serial, 1 x parallel,

and 2 x PS/2 connectors. Linux support

is good, although you will need the Via

[1] X server or resort to the Framebuffer

X server.

The Yeong-Yang A106 case for 60 Euro

was supplied by Northern Micro [7]. It is

quite compact and does not even look

like a computer at

first glance. The CD

drive is hidden

behind an acrylic

cover in the middle of

the case, and the but-

tons and ports are

concealed.

Low Clock Speed

Low clock speed, energy saving proces-

sors that require only passive cooling are

an alternative. The chip manufacturer

Via launched the highly compact EPIA

motherboard at this year’s CeBIT. The

board is one of the first to use the Intel

which unfortunately turned out to be too

small for the opening in the case. This

meant we could only use one screw to

fasten down the transducer, but there

were no other hitches.

The Casper case is quite roomy with

enough room for four PCI adapters, a

hard disk, a floppy disk and a CD ROM

drive (see Figure 1). Heat can escape

via the case lid, and this allows fanless

operations – however, the internal tem-

perature may rise to 40 degrees and the

motherboard chipset can reach peak

temperatures of 60 degrees.

Fanless Power

Supply

We replaced the inte-

grated 70W power

with a fanless Lex 14-

19V DC 110W ATX

power supply for 125

Euro, from [3]. The

power supply com-

prises two compo-

nents, and external

transformer and an

internal transducer,

Figure 1: The case is compact, but provides ample space for a video

recorder with a CD drive and one or two hard disks. As fanless operation

is possible, the hard disk is the only source of noise, however, the

operating temperature is about 40 degrees

DVB Cards

A wide selection of Digital Video Broad-

casting (DVB) cards is available, but

unfortunately not all of them support

VDR [11]. Cards manufactured by Haup-

pauge [4] and Technotrend [5] should

perform well for satellite, cable, and ter-

restrial reception. The drivers were

mainly written by Convergence [6]

developers.

You have to distinguish between so-

called full-featured and low-budget

September 2003

www.linux-magazine.com

PC Hardware for the Living Room

J ust hot air, that is one way of looking

Fanless Video Recorder

COVER STORY

cards. Full-featured cards include an

MPEG 2 decoder, and allow you to view

the satellite signal on TV without

impacting CPU performance. Prices

range from 160 to 250 Euro depending

on the model and dealer. In contrast,

low-budget models cost somewhere in

the region of 70 to 90 Euro, and provide

only reception facilities without the

MPEG 2 decoder and TV output.

They make perfect backup cards, if

you want to record multiple channels

simultaneously.

revision. The revision number is printed

at the top of the card and provides for

easy identification.

Low-Budget Cards

Be careful when purchasing a low-

budget card. Again, only Technotrend

models proved reliable. Low-budget

cards are sold by a variety of manufac-

turers under a variety of names. The

Hauppauge WinTV Nova (85 Euro) and

Technotrend WinDVB Budget2 (70 Euro

from [5]) passed our tests.

In contrast, the Typhoon TV Sat DVB

[8] does not support VDR: drivers are

available from [9], but Video4Linux sup-

port is unavailable. The extremely

low-priced Technisat Skystar 2 was still

unstable at time of writing – it supports

the current DVB driver, but the project is

still looking for a maintainer to continue.

As a general statement, reliable

support is available for cards with the

Philips SAA7146A chip only at present.

CA modules that allow users to add

a crypto card for pay TV are another

problem – in fact only one full-featured

card supports this at present, and driver

support is lacking for the low-budget

cards.

If you have the money

Technotrend Revision 1.3 DVBs are the

only ones with two satellite connectors –

an input and an output port. As there are

very few practical applications for the

output port, subsequent models (revi-

sion 1.6 and 2.1) have retained only the

input port. The WinTV Nexus card by

Hauppauge [10] is only available in the

current revision 2.1 version. The adapter

is the most expensive of our test candi-

dates (225 Euro), but comes complete

with a remote control and an infrared

receiver. The older 1.3 and 1.6 revisions

are an alternative,

although they pro-

duce more heat

than the new 2.1

revision, they sell

at around 170 to

180 Euros (from

[5]).

Full-Featured Cards

Full-featured cards are all based on a ref-

erence design by Technotrend, and use

various tuner modules depending on the

Figure 2: Full-featured cards, Revision 1.6 top left, and Revision 2.1 bottom

left, are identical apart from the tuner. The low-budget cards, Hauppauge

WinTV-Nova-s (bottom right) and Technotrend WinDVB-s Budget2 (center

right) are absolutely identical; the Satelco card (top right) has a different

tuner

INFO

[1] Via driver page: http://www.viaarena.com

[2] ITX Motherboard: www.mini-itx.com

[3] Power Supplies: http://www.linitx.com

[4] Hauppauge, DVB cards: http://www.hauppauge.com

[5] DVB-Shop, DVB cards: http://www.dvbshop.tv

[6] Convergence: http://www.convergence.de

[7] Northern Micro: http://www.northernmicro.com

[8] Typhoon: http://www.anubisline.com/english/eindex.htm

[9] DVB drivers for Typhoon DVBs: http://www.metzlerbros.de/

mbros/dvb

[10] Scan: http://www.scan.co.uk

[11] Recorder software: http://www.cadsoft.de/people/kls/vdr/

www.linux-magazine.com September 2003

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