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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
144-50
250-56
366-72
478-84
584-90
696-102
7102-108
8156-162
9162-168
10180-186
11186-192
12204-210
13210-216
14234-240
15240-246
16258-264
17264-270
18282-288
19288-294

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
150-56
260-66
366-72
478-84
584-90
696-102
7102-108
8162-168
9180-186
10186-192
11204-210
12210-216
13230-236
14236-242
15258-264
16264-270
17282-288
18288-294


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
144-50
254-60
360-66
466-72
576-82
682-88
7174-180
8180-186
9186-192
10192-198
11198-204
12204-210
13210-216

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.

Channel number Frequency range in megahertz Special notes
14470-476
15476-482
16482-488
17488-494
18494-500
19500-506
20506-512
21512-518
22518-524
23524-530
24530-536
25536-542
26542-548
27548-554
28554-560
29560-566
30566-572
31572-578
32578-584
33584-590
34590-596
35596-602
36602-608
37608-614Not used because this frequency is used by radio astronomy
38614-620
39620-626
40626-632
41632-638
42638-644
43644-650
44650-656
45656-662
46662-668
47668-674
48674-680
49680-686
50686-692
51692-698Not used because of interference problems with mobile telephone service
52698-704deleted 2009, see note below
53704-710deleted 2009, see note below
54710-716deleted 2009, see note below
55716-722deleted 2009, see note below
56722-728deleted 2009, see note below
57728-734deleted 2009, see note below
58734-740deleted 2009, see note below
59740-746deleted 2009, see note below
60746-752deleted 2009, see note below
61752-758deleted 2009, see note below
62758-764deleted 2009, see note below
63764-770deleted 2009, see note below
64770-776deleted 2009, see note below
65776-782deleted 2009, see note below
66782-788deleted 2009, see note below
67788-794deleted 2009, see note below
68794-800deleted 2009, see note below
69800-806deleted 2009, see note below
70806-812deleted 1983, see note below
71812-818deleted 1983, see note below
72818-824deleted 1983, see note below
73824-830deleted 1983, see note below
74830-836deleted 1983, see note below
75836-842deleted 1983, see note below
76842-848deleted 1983, see note below
77848-854deleted 1983, see note below
78854-860deleted 1983, see note below
79860-866deleted 1983, see note below
80866-872deleted 1983, see note below
81872-878deleted 1983, see note below
82878-884deleted 1983, see note below
83884-890deleted 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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