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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.



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.  



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.   



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. 



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                         ****                           




Ó R.Maybury 1997 2609




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