Technology of Q 2500 colour TV set
3.1.1 HF/IF components
3 Receiver components
A HF/IF combination is also used. All func-
tions for current European television stan-
dards are located in one housing, with two
3.1 HF/IF unit provisos. The IF consists of only one picture
Four receive components can be used in de-IF. The audio demodulation takes place in the
vices with Q 2500 chassis. One is the terres-audio IC on the signal board. From the IF
trial tuner, or HF/IF component, which proc-component only the sound IF is supplied as
esses frequencies from 47 MHz to 860 MHz. broadband.
This hyperband tuner is located on the basic This means that the ceramic transducer and
board. an expensive sound/IF switch are not re-
quired. Secondly, for lower price models not
Second is the single SAT or dual SAT receiver destined for export HF-IF, designed only for
for the first IF from 950 MHz to 2150 MHz. PAL and SECAM BG, is used. In this case,
This is partly a standard feature or can be
retrofitted for certain sets. the change-over to SECAM L and NTSC and
the components necessary for this are not
In addition, for full IP sets a PIP-HF/IF unit for required.
the reception of terrestrial signals is incorpo-
rated into the hyperband range. In this case, This means the two designs are hardware and
software compatible.
however, the audio band is dispensed with, as
picture for picture only video signals are re-The following block circuit diagram shows the
quired. This is also built into the basic board. multi-standard design. Some of the compo-
nents are not fitted to the BG version.
With this equipment the set is able to process
all television signals, irrespective of whether
they are received by terrestrial antennae or As in earlier models, the electronics is housed
via cable units, and even when derived from in an HF proof folding housing.
parabolic antennae.
Document Q 2500 44 ? Loewe ProCollege |
ACEC
