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PHILIPS TL24R TIME-LAPSE VCR
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WHAT OUR EXPERTS SAY...
If you’re experiencing a vague feeling of
deja-vu, it might be because from the outside, the Philips TL24R VHS time-lapse
video recorder is virtually identical to its stablemate, the TL720R, (Bench
Test, January 1997). The principle difference between the two models -- apart
from the price -- is the number and
duration of the recording modes. The TL720 has five settings, with a recording
capacity of up to 720 hours; the TL24 is more modestly equipped, with 3, 12 or
24 hour modes. This makes it more suitable for continuous surveillance in
retail premises, with sufficient time-lapse coverage for unattended over-night
operation.
Cosmetically the TL720 and TL24 are two peas
from the same pod, from the design and layout of the front panels, down to the
cream-coloured cabinet. Internally there have been only relatively minor
changes to the recording circuitry, the chassis, tape transport and most other
key components appear to be exactly the same. Both machines use Philips ‘Turbo
Drive’ mid-mounted deck mechanism, which they claim has one of the quickest
fast-winds in the business; spooling a 3-hour tape from end to end takes just
95 seconds. We’re still not entirely convinced this has any major benefits for
routine time-lapse operation, though we take their point, that it speeds up
access time, when searching through a tape looking for a particular sequence.
A rotary jog/shuttle dial and a set of
buttons on the right side of the case control all of the tape transport
functions. The main alphanumeric display panel, with three buttons for the
on-screen display, is in the middle of the panel, beneath the tape loading
hatch. On the right side of the fascia there’s a numeric keypad, used to enter
time and date information, timer settings and make or change menu selections.
The rear panel is equally sparse; a pair of BNC sockets handle the composite
video input and output, audio connections are carried by two phono/RCA sockets.
All of the audio and video inputs and outputs are duplicated on a 21-pin SCART
connector. A rather insubstantial-looking 9-way spring terminal is used for the
alarm input/output and reset, serial input/output, external video switch and
tape-end alarm output. The serial connections are used to couple two VCRs
together, for uninterrupted coverage.
The TL24R has a simple alarm function. When
triggered the deck automatically switches to 3-hour real-time recording mode
for a pre-set period (1, 2, 5, 10, 15 minutes or to tape end). Alarm activation
times are logged and shown on the ‘Alarm Chart’ display. The machine can be set
to switch on and off at pre-set intervals, using a built-in 7-event/31-day
timer. Other features worth mentioning include a PIN coded control lock,
picture quality check system, head drum cleaner and automatic resumption of
recording, following a power failure.
OPERATION
The main menu display has five options
(clock, basic settings, alarm setting, alarm chart and timer) plus an
hour-meter. Inspection and service are recommended at 1000 hour intervals;
Philips suggest the upper and lower drum assemblies and the pressure roller
should be replaced or serviced every 2000 hours. The basic settings menu covers
recording mode, source selection (BNC or SCART), on-screen display enable and
position, camera synchronisation, bleeper and control lock. Alarm Settings
options cover the reset time and repeat recording mode, when the tape runs out.
The Alarm Chart display shows all alarm
times; positioning the cursor over an event and pressing the ‘play’ button
automatically fast-winds to the beginning of the recording and starts replay.
This function is very useful indeed, and it works well. (It was supposed to
have been available on the TL720, though we never managed to find it...) One less
welcome throwback to the TL720 is the lack of alarm indications, after the
machine has reverted back to time-lapse recording, following an alarm.
When the VCR alarm is triggered the letter
‘A’ appears on the monitor output and the recording, (next to the time and date
display), but only for as long as the machine is in the 3-hour recording mode.
The word ‘Alarm’ also appears on the front panel display, however, both
disappear when time-lapse recording resumes. Unless the machine has been
connected to an external alarm device, or the operator routinely checks the
Alarm Chart before exchanging or rewinding a tape, there is no way of knowing
that an alarm sequence has been recorded. Furthermore, if the machine is set to
repeat record at tape end, it will over-write any alarm recordings. The Alarm
Chart will also be erased if the tape is ejected or there is an interruption to
the power supply, lasting longer than a few seconds. A simple LED indicator,
that lights up and stays on -- to show an alarm has been triggered -- is all that’s needed. It would add
relatively little to the cost of the machine and prevent potentially important
recordings from being lost.
PERFORMANCE
We’re pleased to say that the similarities
between the TL720 and TL24 extend to on-screen performance. On test recordings
the review machine was able to cleanly resolve just over 240-lines, at all
playback speeds. Picture noise levels were commendably low, lower still when
using a high-grade tape. Colour accuracy and stability are both good. Still and
slow motion replay are very steady, though the need to hold down the ‘still’
button whilst at the same time turning the outer jog dial (to alter slomo
speed) is a bit cumbersome. Changing replay speed and direction -- using the
jog/shuttle dial -- produces only minor picture disturbance and the jog dial
makes it incredibly simple to step forwards and backwards through a recording,
a frame at a time if necessary. Audio quality on 12 and 24-hour recordings is
surprisingly good, treble response is understandably poor at such low tape
speeds but it’s good enough to make sense of speech and incidental sounds.
OVERALL ASSESSMENT
As far as performance and ease of use are
concerned the TL24R scores well but like the TL720 it is let down by rather
crude alarm facilities. Our main concern is the lack of visual and audible
indicators, that an alarm event has been recorded. Nevertheless, it represents
good value for money, and for applications where an alarm connection isn’t
required, it provides a cost-effective alternative to rival 24-hour time-lapse
machines.
PRODUCT ASSESSMENT
Design and design features ***
Circuitry and components ****
Ease of installation and wiring ****
Range and variety of functions ***
Accompanying instructions ****
Technical advice and backup ****
Value for money ****
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Ó R.Maybury 1997 2609
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