Even a $40 converter-box coupon can’t get TV where there’s an inadequate signal, and a new study by Centris Inc. estimates that 8.5 million households primarily reliant on over-the-air TV will experience some trouble with TV reception.

That’s 58 percent of all households primarily reliant on over-the-air TV. The total figure is a decline from Centris’ early 2008 estimate of 9.2 million.

That study was criticized at the time by many broadcasters on several methodological fronts, as outlined here by TV Technology columnist Doug Lung.

At that time, David Donovan, president of the Association for Maximum Service Television (MSTV) also criticized the Centris study. "It is simply wrong to suggest that DTV service will not be available in areas outside of 30 miles from a DTV broadcast tower," he said, referring to one of the study’s assumptions. Donovan was not immediately available for further comment.

Centris said its latest study—pitched as a report of marketing opportunities related to the DTV transition—“means that a large number of TV viewers will require additional options other than the primary converter box program to continue receiving adequate signals.”

By “other options,” Centris is referring to new antennas as well as subscription TV. For cable providers, new customers might also want voice and broadband services, said Centris President Bill Beaumont.

“Retailers that offer both sales and installation of antenna and other needed equipment may also benefit from selective households wishing to retain OTA reception,” Beaumont said.

Centris estimates that 33.8 million homes that will be affected by the DTV conversion—14.6 million that use on-air analog signals as their primary source of TV, and another 19.2 million with both over-the-air and pay television.

Of the 14.6 million primary OTA households, Centris estimates approximately 6.1 million (42 percent) should be able to receive TV if they purchased and correctly install a converter box.

Centris is selling the complete report for $2,500.