Last June a group of broadcasters and equipment manufacturers filed a letter request seeking changes in the technical specs relative to FM digital broadcasting. The Commission has now opened that proposal up for public comment. Comments are due by November 28, 2008; replies by January 4, 2009.

In a tacit admission that the HD Radio ™ digital audio service may not deliver all that everybody hoped for in the way of signal strength, the proponents have asked for an increase in HD power by up to 10 dB . . . except (according to the proponents’ letter request) that the increase would not necessarily apply to some Super B stations (because higher digital power for those stations were found to have potential adverse effects on the analog signal of first adjacent Class Bs). The proposal would, according to its proponents, result in significantly greater HD coverage areas and improved signal penetration into buildings. Of course, the proponents say nothing but nice things about HD service, but one may well wonder why, if HD service is everything it’s cracked up to be, a significant power increase might be called for. 

Additionally, the fact that even the proponents – who seem to be avid cheerleaders for the HD service – have to carve out some exceptions because of interference concerns does not inspire confidence. While it may be possible that interference would be limited to a particular class of station in particular circumstances, the acknowledgment of any potential interference at least establishes, well, that there is a potential for interference at all. 

Months ago – long before the FCC’s 10/23/08 notice formally opening this up for comment – a number of broadcasters lobbed in fairly strident oppositions.  Those included NPR, which provided several hundred pages of very detailed, and very critical, studies.  Now that the FCC has affirmatively solicited comments, it will be interesting to see what level of response results.