Listed in the November, 1924 edition of The Radio Trade Directory under the heading of manufacturers of vacuum tube sets on page 80, the Krasco Manufacturing Company, Inc. was located at 451 East Ohio Street in Chicago, Illinois.
By the time the February, 1925 edition of The Radio Trade Directory came out the Krasco Manufacturing Company had disappeared to be replaced by the Monarch Radio Corp. at the 451 East Ohio address in Chicago.
 

By the time that the August, 1926 McGraw-Hill Radio Trade catalog was released the Monarch Radio Corp. had a new address listed of 111 West Monroe Street still in Chicago.

Former Krasco Manufacturing Co. Inc.is 1929: Krasberg Tool & MFG. Co.; Chicago, Illinois, Room 811-111 W. Monroe Street (Tel. Randolph 3824).

Trade Name: "Monarch" and "The Tollos Radio". Folder: Gollos phase splitting circuit, "the ACME of perfection".

Full paged ad with picture on page 13 of Radio Engineering, Novermber 1929: "Krasberg's new patented automatic record changer and phonogrph, the Musicaphone, will make new radio merchandising history and profits for radio manufacturers, jobbers and dealers. Successfully changed 12,000 records at the Radio Show. Capacity - fifteen ten-inch standard records."

See also Radio Engineering Vo. X., January 1930, No. 1 on page 60 about the Krasberg Musicphone. There is an article and two pictures.