I'm not sure what the circle for 1 sec over tone is but the last show I did that went to PBS has a silent video slate for 10 secs (from 59:40:00 to 59:50:00) then add numbers for 1 second each from 10 to 2. (59:50:00 to 59:58:08) The 2 actually lasts 8 frames leaving the proper black before beginning of show. For each second of video make a 1K tone at -20 for 20 frames and then 10 frames of 1K tone at -40.
Make a nice background from a shot of your facility and put the information of the slate over that. I keep a clip in the NLEs for this purpose.
This works for me but you might go on PBS Connect for an absolutely definitive answer.
fire*, smoke*, photoshopCS3
Charlotte Public Television