[BC] AM maintenance question

[Dave Hultsman]

In a message dated 2/14/2010 6:08:40 PM Central Standard Time, john at mayson.us writes:
> Do AM stations still routinely sign off Sunday night/Monday morning for transmitter maintenance? I recall hearing in the late 60's WABC going off for a few hours then coming
The FCC rules used to specify that experimental period is the time between 12 midnight and 6 AM local time.  Many 24 hour stations that did not have back-up equipment usually signed off on Sunday night for a period of time for two or three engineers to check AC and DC connections, blower belts, RF connections, change air filters and clean the equipment.
 
For a while in the early 1960s in Dallas the only stations on the air on Sunday night were KRLD and WRR. All of the other stations signed off for maintenance. This maintenance could be done on any night during the experimental period.
 
Dave Hultsman