OK, I've gone back through the evidence. The answer to the question:
NO EARLIER THAN FEBRUARY 17, 2009, and
ONE MIGHT STILL BE ON THE AIR!.
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For some time, I believed channel 70 in Herington, Kansas was the last translator operating above channel 69. This station relayed KAKE channel 10, Wichita. It was reported seen by DXers as late as 2000.
The question came up on Radio-Info yesterday, and I have found information that one translator operated on channel 70 at least as late as September 2007, and another one **is probably STILL OPERATING ON CHANNEL 70**.
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On September 26, 2007, K70FL in Hartsel, Colorado filed an application to move to channel 23. It takes some time for FCC action on these displacement applications. So on the same date, the station also filed for Special Temporary Authority to make the move without waiting for action on the displacement application. In that application, available online at
http://licensing.fcc.gov/cgi-bin/ws...7330&Service=TX&Form_id=346&Facility_id=10087
they stated in part: "A LOCAL PUBLIC SAFETY ENTITY REQUIRES THAT CHANNEL 70 BE VACATED IMMEDIATELY." Obviously, this implies that as of the date of filing, at the end of September 2007, K70FL was in fact operating on channel 70.
(The Temporary Authority was approved the next day. The application for permanent operation on channel 23 was approved in November 2007. However, no license-to-cover was ever filed, and the station is now listed as "DK70FL" implying the license has expired or been canceled.)
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But K70FL was not the last station on channel 70.
The engineers at KTTC-TV, Rochester, Minnesota blogged their work on DTV Transition Day. (KTTC transitioned on the originally-planned date of February 17, 2009) You can read that blog on
http://addins.kttc.com/blogs/dtv/ .
The entry for 6pm on February 17:
"6:00 PM - John has finished up at Blue Earth. Channel 70 out there is now re-broadcasting KTTC once again."*
As of February 17, 2009, K70DR Blue Earth, Minnesota WAS STILL OPERATING ON CHANNEL 70.
The station has a permit to switch to digital operation on channel 16.
* They had to make changes to the receiver used to pick up the main KTTC signal for rebroadcast. KTTC-DT moved from channel 36 to channel 10 on Transition Day.
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Are there others out there?
W70AP Lovingston, Virginia is still licensed. This station is a translator of WCVE-23, Richmond. The station's license was renewed in July 1998. I see no applications of any kind. (beyond the license renewal) Best I can tell, it's still authorized to operate.
W70AP and K70DR are the only two stations still holding valid licenses for channel 70. No station holds a valid license for any higher channel.
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It does beg the question, what's the point?! New TV receivers have not tuned above channel 69 for many years. I would educated-guess the answer falls into two categories:
- Cable systems.
- Other translators. (not in KTTC's case)