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OPINION

EXPERT

+

RECOMMENDED

PRODUCT BY

Vitor Martins

Augusto

Test Center

Portugal

Titanium C1W-PLL

C band LNBF

50

TELE-audiovision International — The World‘s Leading Digital TV Industry Publication

— 01-02/2015

TELE-audiovision.com

● Great gain

● Great Noise Figure

● PLL Technology

● None

a remarkable feature of the

C1W-PLL this is.

Because the C1W-PLL

LNBF was quickly able to

demonstrate how good it

is, we spent the rest of the

afternoon entertaining our-

selves hunting for exotic

transponders. The pictures

show a selection of three

such transponders that were

captured in Feedsat’s garden

in the French countryside.

The brand new Titanium

Satellite C1W-PLL wideband

LNBF is hands down the best

bargain any C-Band enthu-

siast can find for his money

- and, of course, any profes-

sional as well. When it comes

to the price/quality ratio, we

were totally surprised by this

unique PLL LNBF and its re-

ception results. Granted, a

hardcore enthusiast might

still prefer to use a profes-

sional C-band LNB with skew

control, but for most C-Band

users, this LNBF will provide

exceptional reception results

at a fraction of the cost.

Add to this a relatively low

power consumption of just

108 mA, a heat sink for en-

hanced stability and an unu-

sually low noise figure.

For our test in Europe we

used the wideband range

model (3.4GHz to 4.2GHz).

Titanium Satellite also of-

fers a model for the US mar-

ket with the regular band

of 3.7GHz to 4.2GHz. So be

sure you know which band

you can receive at your lo-

cation.

What is PLL?

PLL stands for Phase-Locked Loop and represents

a method to generate an output signal that is in

phase with the input signal.

When a digital satellite signal is received by the an-

tenna, the LNB is used to convert the input signal, in the

case of the wideband C-band from 3.4 GHz to 4.2 GHz, to

the IF range of 950 MHz to 1750 MHz, which is what is

needed by the satellite receiver’s tuner.

Because the signal represents a continuous flow of bi-

nary data, it is crucial to keep the signal synchronized, so

that no piece of information is lost due to fluctuations in

the timing. If there is such a delay, bits of information

may be missed or interpreted twice, producing errors.

The higher the information density, the more critical it

becomes to have a correct phase of the signal. This is es-

pecially true for DVB-S2 signals with high FEC rates. With

an FEC of 7/8, seven out of every 8 bits represent data,

while just one bit is used for error correction. In order

to get good reception, it is crucial to have a very stable

output signal from the LNB.

To maintain the output signal in phase with the input

signal, most LNBs rely on an oscillator. For C-band LN-

BFs, the oscillator frequency would typically be 5.15 GHz.

There is a small deviation of this theoretical frequency,

due to imperfections in the crystal, temperature fluctua-

tions, etc. This is why regular C-band LNBs struggle with

signals that have low symbol rates or high FEC values.

To get greater stability, high-end LNBs for professional

use often use an additional external 10 MHz reference

signal, combined with a PLL oscillator.

The PLL oscillator basically uses the input phase to syn-

chronize the internal oscillator, thus compensating for

the oscillator’s deviations. The result is a perfectly timed

output signal, which is in phase with the input signal.

This requires a rather complex circuit and hence the

usually higher cost of PLL LNBs; though not so with Tita-

nium’s PLL series of LNBFs.