NEW YORK — Delaying the upcoming digital TV transition for four months would cost public broadcasters $22 million, the PBS system chief estimated on Monday. Paula Kerger, president and CEO of the Public Broadcasting System, said she hopes lawmakers keep that in mind as they consider legislation to delay the switch from Feb. 17 to June 12. The stations will face increased power charges to maintain over-the-air broadcast signals, she said. Many have leases for signal transmitters that were due to expire on the date of the switch over and will have to make new arrangements, she said. "This is such a tough situation for our stations because they have just gone through a process where they have raised the money to go through this transition," she said. The Obama administration has sought the delay because the government program to provide coupons for converter boxes needs more money. The boxes are needed for people without cable or satellite TV to continue receiving TV signals after the conversion date. The latest estimate is that more than 6.5 million households are not prepared for the switch over. The National Association of Broadcasters has not taken a position on extending the deadline. The TV stations don't want to suddenly alienate and lose viewers, but they've also sunk money into preparing for the Feb. 17 transition. Kerger said that PBS is not supporting either side, but he doesn't want PBS' hardships lost, among potential hardships faced by viewers. "At the end of the day, our interest is public service and we want to make sure that people don't go without television," she said. There's a possibility that TV networks would be allowed to choose whether to make the switch over on Feb. 17 or delay it, in which case Kerger said it's likely that PBS would allow its individual stations to choose for themselves. In lobbying for government help to the system, Kerger noted that much of the costs for the digital transition have been paid through fundraising, which in some cases has made less money available for programming.