Instruments that are extensible – in terms of their feature set – and upgradeable, in parametric terms, are popular: as the manufacturers' documentation says, you are protecting your investment by not having to purchase a new unit when you move your own technology on. As more and more of the features of T&M instrumentation has come to be defined in software, it has also become common that the instrument you buy is capable, and fully-equipped, to operate at a higher specification than the one you initially purchase. A software key, that you subsequently purchase, enables more advanced performance than you bought at the outset. This benefits the manufacturers, who can limit the number of variants that they build (and they lock you in as a customer): and it means that your instrument is not obsoleted quickly, and does not have to return to its maker to receive an upgrade. It also enables the T&M vendor to offer you an “entry-point” specification – as distinct from an entry-point instrument – at a price that may fall into a lower capital-expenditure category.
Tektronix has applied all of these marketing strategies to its new MDO3000 series of oscilloscopes – or, not just scopes, as Tek refers to this range as six instruments in one, the six being scope, spectrum analyser, logic analyser, protocol analyser, arbitrary function generator and DVM. The spectrum analyser function follows the pattern that Tek set with the MDO4000 series in that it is a separate full-function channel, and not an FFT-derived analysis function applied to the main oscilloscope inputs.
By applying the expansion options approach outlined above, Tek offers an entry point that starts at €2,700/£2,250, and you get a spectrum analysis function to match the scope bandwidth you initially order; Tek says its customer research shows that over 25% of oscilloscope users now use a spectrum analyser multiple times per week – and that over 40% of embedded design projects include some form of wireless capability. EMI test is a major use of the spectrum analysis function.
The 3000 instrument “platform” can be upgraded in the field. Performance upgrades include analogue bandwidth of the oscilloscope and input frequency of the spectrum analyzer. Functional upgrades include the addition of digital channels, protocol analysis, arbitrary function generation or digital voltmeter measurements. Bandwidth upgrades, for both scope and spectrum analyser, are tied to the specific serial number of the instrument – although you enable the upgrade by software key, Tek will send you a new front-panel label in the mail. Certain other features – such as the protocol analyser, and specific protocols that you might purchase, are enabled by plug-in tokens that you can transfer between similar instruments. The DVM is not enabled at purchase, but you get that in return for registering the instrument.
The MDO3000 Series oscilloscopes feature 2 or 4 analogue input channels with bandwidth ranging from 100 MHz to 1 GHz, 16 digital channels (optional) and one RF input channel matching the bandwidth of the oscilloscope (9 kHz up to analogue bandwidth). The RF input frequency on any model can be extended to 3 GHz.