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‘New’ System Is Based on a Delusion, Kumar Writes

Reacting to the story “High-Definition Expanded Radio” on RW Online, Derek Kumar of Digital Radio Express writes in reply.

Reacting to the story “High-Definition Expanded Radio” on RW Online (see below), Derek Kumar of Digital Radio Express writes in reply:

Shame on Radio World. You’ve just helped Hal Walker fool a new generation of readers with the dubious VMSK technology. First off, this so-called system isn’t even an FM SCA — it’s more of an IBOC/IBAC thing. Did you even bother to look at their own Web site The spectrum clearly shows the VMSK signal on only one side of the standard FM modulated carrier. This is physically impossible with a true FM SCA system. Moreover, VMSK is a delusion. It was debunked years ago by Phil Karn of Qualcomm, among others. Must-reading includes

VMSK puts virtually all of the energy in the carrier so that the data-bearing signal is “in the grass.” Of course, it is useless at this level. Unfortunately, along the way, small investors have lost a lot of money through the various shell companies involved (Pegasus Data Systems, AlphaCom) and now this.

You have done a disservice to your readers, many of whom do not have the technical acumen to determine what is a perpetual motion machine and what is not. That’s not their fault — broadcasting is more about content than technology — but it is even more reason for technical editors to do proper due diligence before giving such claims front-page attention.

Derek Kumar
Digital Radio Express, Inc.
Milpitas, Calif.