Radio-TV Broadcast History
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The very high frequency (VHF) band[]

Prior to 1934, no frequencies were specifically for television, but experimental stations were assigned frequencies at various points in the spectrum. Many were high (opposed to "very high") frequencies such as 2.1 MHz. In 1934, frequency bands were set up by the FCC covering 42-46 and 60-86 MHz, but without specific channels assigned.

In October 1938, the first tentative channel assignments were made. Nineteen channels were allotted as shown in the table below. However, because the FCC had not yet adopted standards for television broadcasting, hearings were held, and on December 22, 1939, a set of rules was adopted for limited commercial television broadcasting. However, different manufacturers wanted different standards, and it took until February 29, 1940 before FCC rules permitting limited commercialization effective September 1 went into effect.

Channel number Frequency range in megahertz
1 44-50
2 50-56
3 66-72
4 78-84
5 84-90
6 96-102
7 102-108
8 156-162
9 162-168
10 180-186
11 186-192
12 204-210
13 210-216
14 234-240
15 240-246
16 258-264
17 264-270
18 282-288
19 288-294

It will be noted that there are gaps between many of the channels, and most of the channels are grouped in pairs of adjacent frequencies (except for channel 3). There are two big blocks, a low band (44-108 MHz) and a high band (156-294 MHz), a forerunner of the eventual system.

On June 20, 1940, the 44-50 MHz channel was taken away from television, and assigned to FM broadcasting. Most of the channel numbers were lowered by 1 in consequence of this; some of the gaps were adjusted, so the resulting arrangement was as follows:

Channel number Frequency range in megahertz
1 50-56
2 60-66
3 66-72
4 78-84
5 84-90
6 96-102
7 102-108
8 162-168
9 180-186
10 186-192
11 204-210
12 210-216
13 230-236
14 236-242
15 258-264
16 264-270
17 282-288
18 288-294


In April 1941, the FCC finally adopted the 525-line standard and declared that commercial broadcasting would begin July 1.

On June 27, 1945, the FCC reduced television's allotment to 13 channels: the gap between the low and high band was widened, and all the channels above 230 MHz were dropped; the 44-50 MHz channel which had been dropped in 1940 was restored, and the gaps between adjacent channels were mostly eliminated; the FM band was moved to its current VHF band (moving the lower numbered channels down again) (See List of United States FM frequency allocations). Thus the new lineup was:

Channel number Frequency range in megahertz
1 44-50
2 54-60
3 60-66
4 66-72
5 76-82
6 82-88
7 174-180
8 180-186
9 186-192
10 192-198
11 198-204
12 204-210
13 210-216

On June 14, 1948, channel 1 was taken away, so that the television channels were numbered 2 to 13 with no 1. This became the permanent frequency allocation for the VHF television channels in the United States.

The ultrahigh frequency (UHF) band[]

By 1952, it became obvious that twelve channels would not be enough; even the 19 originally envisioned were thought to be insufficient. So seventy additional channels, numbered 14 to 83 as below, were allocated in the ultrahigh frequency part of the spectrum. The first UHF station, KPTV, in Portland, Oregon, went on the air on Channel 27 on September 18, 1952. However, this proved not to solve the problem very well, as most television sets could not receive the UHF channels until the FCC mandated in 1964 that new television sets had to be built with tuners that included the UHF channels. Because the UHF channels never became as popular as had been anticipated, in the 1980s, channels 70-83, which in fact had been reserved for repeaters anyway, were deleted from the television allocations and the frequencies were reassigned to cellular telephone use. On June 12, 2009, in conjunction with the switch from analog to digital television broadcasting, additional channels were deleted; everything from channel 52 up. In 2017 the FCC started to reallocate channels 38-51 to cell phone companies for LTE and 5G coverage. On July 12, 2017 TV stations that broadcasted on channels 38-51 were assigned a new frequency and were scheduled to move during one of 10 assigned phases. The first phase was completed on November 30, 2018 and the last phase is planned to be completed by July 3, 2020. Due to Covid-19 and a limited number of people qualified to work on broadcast towers, it is expected that the repack will continue to early-mid 2021.

Channel number Frequency range in megahertz Special notes
14 470-476
15 476-482
16 482-488
17 488-494
18 494-500
19 500-506
20 506-512
21 512-518
22 518-524
23 524-530
24 530-536
25 536-542
26 542-548
27 548-554
28 554-560
29 560-566
30 566-572
31 572-578
32 578-584
33 584-590
34 590-596
35 596-602
36 602-608
37 608-614 Not used because this frequency is used by radio astronomy
38 614-620
39 620-626
40 626-632
41 632-638
42 638-644
43 644-650
44 650-656
45 656-662
46 662-668
47 668-674
48 674-680
49 680-686
50 686-692
51 692-698 Not used because of interference problems with mobile telephone service
52 698-704 deleted 2009, see note below
53 704-710 deleted 2009, see note below
54 710-716 deleted 2009, see note below
55 716-722 deleted 2009, see note below
56 722-728 deleted 2009, see note below
57 728-734 deleted 2009, see note below
58 734-740 deleted 2009, see note below
59 740-746 deleted 2009, see note below
60 746-752 deleted 2009, see note below
61 752-758 deleted 2009, see note below
62 758-764 deleted 2009, see note below
63 764-770 deleted 2009, see note below
64 770-776 deleted 2009, see note below
65 776-782 deleted 2009, see note below
66 782-788 deleted 2009, see note below
67 788-794 deleted 2009, see note below
68 794-800 deleted 2009, see note below
69 800-806 deleted 2009, see note below
70 806-812 deleted 1983, see note below
71 812-818 deleted 1983, see note below
72 818-824 deleted 1983, see note below
73 824-830 deleted 1983, see note below
74 830-836 deleted 1983, see note below
75 836-842 deleted 1983, see note below
76 842-848 deleted 1983, see note below
77 848-854 deleted 1983, see note below
78 854-860 deleted 1983, see note below
79 860-866 deleted 1983, see note below
80 866-872 deleted 1983, see note below
81 872-878 deleted 1983, see note below
82 878-884 deleted 1983, see note below
83 884-890 deleted 1983, see note below

Channels 70 to 83 were deleted in 1983 by a worldwide convention which reassigned those frequencies to the Land Mobile Radio System (Public Safety and Trunked Radio) and mobile phones.

In 2009, television was converted to digital, and channels 52 to 69 were deleted.

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