Steve and this Steve were both right.  KYW originally moved from Chicago to 
Philly in 1933.  IN the 1950's, they swapped calls with Cleveland, but recovered 
KYW in 1965.  A link with history of the station is at:
http://www.broadcastpioneers.com/kywstory.html
In June 1924, the KYW frequency was changed to 1020 kc and the results were 
disastrous. In many places in Chicago, the KYW signal could not be received,
fortunately the station was permitted to change back to a lower frequency, 570 
kc.

In 1925 KYW moved to the roof of the Congress Hotel and a high powered (20 Kw) 
transmitter was installed. This was the first water cooled transmitter in the 
mid-west area.

In 1923, Westinghouse had installed a transmitter with call letters KFKX in 
Hasting, Nebraska to relay KDKA programs and also to originate some programs for 
the local area. In 1927, KFKX operations in Hastings were discontinued and the 
license moved to Chicago where KYW and KFKX shared time. (The move of KFKX to 
Chicago was made in anticipation of the upcoming 1928 frequency reallocation). 
Finally the Commission is effect said "quit kidding yourselves, which license do 
you want?" So the KFKX license was deleted.

In the November 11, 1928 frequency reallocation, KYW was again assigned to 1020 
kc with the same disastrous effect on the station's coverage in Chicago.
To improve coverage in the Chicago area, a 500 watt synchronized booster station 
KYWA was installed on the roof of the Edgewater Beach Hotel. This improved
the coverage in the North Side area but did not help the main problem so plans 
were made to move KYW to a new site out in the country, near Wheaton, Illinois,
and at the same time the studios were moved to the Strauss Building and 
arrangements made for the Chicago Herald and Examiner to take over the program
and sales operations of the station.

The 1020 kc frequency assigned to KYW in the 1928 frequency reallocation had 
been, in the Davis amendment (the Davis amendment divided the country into five 
zones with all available broadcast frequencies divided equally among the five 
zones) assigned to the third zone, as well as new applicants applied for the 
1020 kc frequency creating an almost continuous legal battle for KYW to protect 
its frequency assignment.

Finally, in 1932, KYW applied to the Commission to move to Philadelphia. The 
application was granted on October 27, 1933 for the facilities at this site.

The new KYW transmitter for the Whitemarsh location was the first all AC 
operated high powered transmitter, no rotating equipment except water pumps for
circulating cooling water for the power tubes (now even the power tubes are air 
cooled). The antenna, a four tower array consisting of steel poles mounted
on wood sub-bases was the first directional antenna designed to suppress 
sky-wave radiation while providing the required horizontal directional pattern.

As part of the move of KYW from Chicago to Philadelphia, arrangements had been 
for WCAU personnel to handle the program and sales operations of KYW and
for Westinghouse personnel to take care of all technical operations. The KYW 
studios were located in the WCAU building on Chestnut Street. I worked with
Jack Leitch, then Chief Engineer of WCAU on the layout and design of the studios 
for KYW. Jack was certainly a fine man to work with during the daytime
but it was awfully tough trying to keep up with him at night.

In May, 1938, KYW studios were moved into the KYW Building at 1619 Walnut Street 
and NBC took over the programming and sales operations. This arrangement
with NBC continued until July, 1940 when Westinghouse resumed the programming 
and sales operations of all the Westinghouse stations.

About the move out of the WCAU Building, some KYW personnel commented that KYW 
had gotten a divorce from WCAU on the ground of incompatibility.

On January 16, 1941, the power of KYW was increased from 10 kw to 50 kw and 
March 29, 1941 there was a frequency reallocation in which KYW's frequency was
changed from 1020 kc to 1060 kc.

In 1949, the present directional antenna system consisting of two IDECO 450 foot 
steel towers which had better radiation efficiency than the shorter steel
poles, was installed.

In January, 1956, Westinghouse and the National Broadcasting Company swapped 
their Philadelphia and Cleveland stations and KYW moved to Cleveland. On June
19, 1965, by action of the Department of Justice and by order of the Federal 
Communications Commission, the swap was reversed and KYW moved back to 
Philadelphia
where we still are.

In 1965, KYW changed its programming to a 24 hour all news operation which, in a 
way, would be repeating the very successful 1922 "World Crier" news operation
but on a much more highly sophisticated basis.

Steve, K8SP