PBS put forth a new framework for thinking about its relationship with member stations last week, asserting that they’re all in the same boat, endangered by common competitors and capable of saving themselves through collective action through PBS. For PBS, the timing of the Fall Planning Meeting could hardly have been better, since many station executives were favorably impressed with the recent $75 million Reader’s Digest Association program deal. President Ervin Duggan laid out a “station equity model” that will guide the network’s actions and pledged that PBS will add 50 percent to the funds wielded by its chief program executive by the year 2000 — an increase from $110 million to $160 million. The Reader’s Digest commitment amounts to one-quarter of that gain, he said. The station equity model calls for “pointed, strategic, coherent” management by PBS of the system’s brand, program rights and other national assets of the stations, Duggan said in a Current interview after the Nov.