in the US VHF low (2-6): 100 kW video analog at in Zone I and in Zone II and Zone III above average terrain; 10 kW in Zone I and 45 kW in Zone II and Zone III digital at above average terrain VHF high (7-13): 316 kW video analog at in Zone I and in Zone II and Zone III above average terrain; 30 kW in Zone I and 160 kW in Zone II and Zone III digital at above average terrain UHF (14-36): video analog at above average terrain; digital at above average terrain Notes: All full-power analog television station transmissions in the US were terminated at midnight Eastern Daylight Time on June 12, 2009. Many broadcasters replaced their analog signal with their digital ATSC signal on the same transmission channel at that time. All US digital stations received a -DT suffix during the analog-to-digital transition. At analog shutdown, the FCC assigned to each digital station the call sign its associated analog station had used. (with a -TV suffix if the analog station had this suffix, without the -TV suffix if the analog station didn't have it). Stations could optionally choose to keep the -DT suffix. Most stations did not keep the -DT suffix. For US analog stations, the -TV suffix was required if there was a radio station with the same three- or four-letter callsign. Stations not required to use the -TV suffix may optionally request it if desired. Analog audio power was limited to 22% of video. Full-power stations in Canada Class A: UHF, 10 kW video/ EHAAT Class B: UHF, 100 kW video/ EHAAT Class C: UHF, video/ EHAAT (?) Class D: UHF, more than / EHAAT Class R: VHF, 100 kW low-band (channels 2–6), 325 kW high-band. (channels 7-13) Class S: VHF, more than 100 kW low-band/325 kW high-band. Notes: Official definitions of these classes are difficult to locate. The values above are inferred from the Industry Canada database. There is some ambiguity about the difference between Classes C and D. Power-level limitations are not firmly enforced in Canada, and Industry Canada has been known to license stations for power levels much higher than the generally accepted limits. For example, CFRN-TV in Edmonton, Alberta operated on Channel 3 at over 600 kW but was not subject to international co-ordination due to its location north of the border. In Canada, the callsigns of all private