The bench test 3: Mux factor

Of course this is not necessarily a bad thing – in theory at least, it ensures that all the bits in a system should work together – but it can make it difficult to mix and match devices that may be better suited to a particular application.

The Appro MPX-9016 16-channel colour multiplexer certainly could not be accused of being anti-social. In fact, the designers appear to have gone out of their way to make sure it will fit in with as many different camera and recording device permutations as possible.

What is more, several of the more tedious configuration routines have been automated, making it reasonably installer-friendly, though it is not without its foibles and funny little ways. Nevertheless the feature list looks impressive.

The 9016 is a full spec duplex design that allows simultaneous playback and recording (with two VCRs). Installation is greatly simplified with the use of auto VCR recording speed detection and synchronisation, which means it can work with the widest range of devices, moreover it is able to replay tapes recorded using many other manufacturers' multiplexers.

Display options include user-set sequencing, single and multi-screen PIP, quad, 3 x 3 and 4 x 4. It has advanced individual motion sensing for each camera channel, video loss and 16 alarm sensor inputs, electronic 2x zoom with pan and tilt, camera titling and brightness control, alarm logging, covert camera operation, password protection and three relay outputs.

Appro has studiously avoided any attempt to make the MP-9016 (or any of its four and nine camera stablemates) stand out from the crowd. It is housed in a slim plain beige case that can be freestanding or rack-mounted.

Uncontroversial
On the front panel there is a long unbroken row of 24 identical buttons, most of them with associated indicator lamps, 16 of which (left side) are the camera selectors. The others are for mode selection, menu navigation and display layout.

The rear side is almost as uncontroversial, but not quite. The thin case means it is quite crowded. There are two tightly-packed rows of BNC connectors for the camera inputs and loop-throughs, VCR in/out, and two monitor (main and call) outputs.

Four four-way mini DIP switches, spaced at intervals between the camera sockets, switch the inputs terminations between 75 Ohm and high impedance. There are also two four-pin mini DIN sockets for S-Video input, and output for a S-VHS/high-band VCR.

On the far left are two female 25-pin D-sub connectors into which plugs a contraption called the expansion board.

This works as a cable 'break-out' for the 16 associated alarm/sensor inputs, alarm output, external VCR triggering, RS232 remote control and an optional VGA video output. While in principle this looks like a sensible idea, the expansion board is quite bulky and increases the depth of the installation by at least 10cm. This virtually negates any size advantage it might have over larger designs.

It could also be a problem in some circumstances if the added depth is not known about until the unit is unpacked. The board looks like a clumsy afterthought and we can see it causing difficulties.

Fortunately it is a reasonably simple problem to resolve with a pair of 25-pin to 25-pin cables, but a more elegant solution could have been devised in the first place.

Set-up & operation
Installation is reasonably intuitive, but once again it could have been better. The on-screen menu display, which is called up by pressing and holding two front panel buttons, looks as though it is based on the graphics chip of an ancient Sinclair ZX81 computer.

The main menu uses a painfully small character set, which makes it unnecessarily difficult to read.

  It is not as if there is a space problem and all of the options are cramped into the top third of the screen.

It is not all bad news though. On some set-up menu screens there is an inset PIP screen, which can be very helpful. Even so, in most cases the text is still much smaller than it needs to be.

It looks as though it has been designed in a hurry, by someone with very little experience in on-screen display design and layout.

The main menu has seven options (time/ date/ title, sequence, VCR operation, alarm operation, camera type/ brightness/ covert, password/ comms and test pattern and motion detection setup), which each leads to a set of sub-menus.

Incidentally, the test pattern – a set of colour bars – is a very handy utility for setting up monitors and cable testing. Most operations are straightforward, and the motion detection facility deserves special praise.

It is very flexible, with variable target size and ten levels of sensitivity. However set-up and configuration are a little unconventional and it does take a while to get to grips with it. The camera set-up menu is also worth a mention and the variable brightness control is a definite bonus.

Performance
Video processing is exceptionally clean with no visible artefacts and no apparent increase in noise levels. The live monitor image is sharp and crisply defined, with no (significant) loss of colour fidelity.

Manual and sequence camera switching is fast and there is no loss of stability. The electronic zoom feature is a notch up on the norm.

The 'pan & tilt' effect displays an opaque preview screen which appears momentarily, clearly showing which part of the image is being enlarged.

From a performance standpoint, the Appro MPX-9016 gets a very clean bill of health. What goes in comes out more or less unscathed – the image is crisp, steady and accurately rendered.