This is most definitely Wrigley Field and the field announcer with the giant megaphone is Pat Piper. Mr. Piper is as revered by people of a certain age in Chicago as Bob Sheppard is in New York. I remember hearing him at Wrigley as a kid in the late 60's as his voice would come over the public address system and boom:
"Attention....your attention please. Please get your pencils and scorecards ready and I will give you the lineup for today's ball game".
I miss hearing that in person...or perhaps I just miss being that young age and being at a ball game where money and contracts didnt mean much to a 7 year old baseball crazed kid.
https://youtu.be/H1OyGeEdc1s