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New Feature - Historic Allotments

Once upon a time, I started RabbitEars (with Bruce's help) with a goal of providing information on stations' technical operations, their programming, as well as their history. While the first two have been well represented, the third has been... lacking, to say the least. I never really made any in-roads with it.

That changes now. I'm pleased to announce a new feature on RabbitEars, Historic Allotments. You'll find this in the Listings drop-down menu. It contains a record of every TV allotment that ever existed in the analog TV table of allotments, stretching from 1945 through the end of the digital TV transition. You can watch how the allotments changed over time, see what changes happened on particular dates, and even plot the allotments on a map.

Already, I'm considering adding another function to it beyond the current Table, List, Changes, and Map functionalities, but I think this is enough to launch it with. Be sure to read the documentation if you have questions. I look forward to hearing feedback!


1. On Friday, June 5 2020, 05:46 by Bigpine

There is another FCC Historical database missing. Television translator call signs. These low power signals were first assigned to rural areas. Mostly used on channels 2 to 13. Then later on the UHF translator band channels 70 to 83. Which was discontinued in 1983.

2. On Friday, June 5 2020, 20:01 by Brian in CT

Well done on the historic NTSC channel allotments! I was playing around with it for at least an hour today. Opening the tool to show allotments at the end of the license freeze is perfect. I also like all the bells and whistles. I have one suggestion. Instead of a blank screen for June 12, 2009, you can list the official digital allotments for the switchover to ATSC. Of course, some users will then want a DTV allotment history, so that can open a can of worms for you. Keep up the good work!

3. On Sunday, June 7 2020, 11:43 by Doug W9WI

First, this new feature is fascinating! I thought I knew everything about the history of allocations in Milwaukee & Madison -- that has been proven dramatically wrong:)
Trip, many thanks!

Bigpine: I'm working on that...
The legal translators started on 70-83 in 1956. There were VHF translators before that -- but they were illegal.
In 1960 the FCC gave up on forcing translators to UHF and began licensing VHF systems.

My research is still in progress but it looks like authorization of new 70-83 translators came to an end in 1973. Those which were already licensed were allowed to continue as long as they didn't interfere with land mobile. Best I can tell, the last one went off the air in **2011**. (in Blue Earth, Minnesota.)

4. On Sunday, June 7 2020, 11:57 by Doug W9WI

Brian: That would be interesting to see but probably quite a bit of work:)

There was really a sea change in policy with the digital conversion.

In analog, a channel would not be assigned unless a station could use it at the maximum permissible power/antenna height -- even if the station didn't intend to use the maximum power. (FM works the same way)

In the digital conversion, and in the repack, stations are only protected in the area they reach with their existing facilities. That's how frequencies are assigned for AM radio, but it's new to television.

I would suggest that takes a lot of importance out of the allocation tables. The existence of channel 68 in the analog tables in Fond du Lac, Wis. clearly precluded use of the channel in Chicago.

The existence of channel 5 in the digital tables there doesn't necessarily preclude its use in Chicago. If the Fond du Lac station ran only a few hundred watts -- a Chicago station could be shoehorned in on the same channel. Especially if Chicago also ran less than channel maximum power.

5. On Sunday, June 7 2020, 21:29 by Brian in CT

Doug, thanks for the information about how DTV "allocations" work. I knew the FCC was packing the DTV stations in like sardines, now I know how they're able to do it. The main reason I wanted such a list for June 12, 2009 was to see which broadcasters stayed on frequency, and which ones changed RF channels. Of the latter, you would be able to check out which stations switched from UHF to VHF and vice versa. I guess that would be another project.

6. On Monday, June 8 2020, 15:22 by Trip


I've considered adding digital information to it, including during the transition. But it's a lot of additional work. I didn't want to hold up the release of the tool and its analog data to wait for the inclusion of digital data that may not get done in a timely fashion (or at all). I've been working on this project on and off since at least 2014, if that gives you a sense of the time involved.

There's still more I'd like to do here, but just getting here was an enormous lift. 99% of the time and effort that went into this was research and data entry, as opposed to writing code, which is what I usually have to do on a project like this. We will see what comes of it.

But I'm glad you like it!

7. On Monday, June 8 2020, 17:27 by Brian in CT

Wow! I didn't realize it took six years for this project to come together. I guess you made many trips to the FCC archives. Now that Doug explained to me how allocation tables are obsolete with digital TV, my original suggestion probably isn't worth the trouble. As I described in comment five, it would still be interesting to see all the RF channel changes (and those that stayed put) for the DTV conversion.

8. On Tuesday, June 9 2020, 04:03 by dhett

Oh my. A history junkie like myself could spend a lot of time on this feature. Yet another challenge to my self-discipline. This looks fantastic - well done, Trip!

Doug - I look forward to seeing the results of your research. There has got to be a real treasure trove in a state like Arizona.

9. On Friday, June 26 2020, 20:42 by DH

I'm personally curious to see a map of any city with a analog VHF allocation.

10. On Tuesday, July 7 2020, 12:04 by Armando Enriquez

good morning, Christy Gior.