The Pan-American television frequencies are different for terrestrial and cable television systems. Terrestrial television channels are divided into two bands: the VHF band which comprises channels 2 through 13 and occupies frequencies between 54 and 216 MHz, and the UHF band, which comprises channels 14 through 36 and occupies frequencies between 470 and 700 MHz. These bands are different enough in frequency that they often require separate antennas to receive (although many antennas cover both VHF and UHF), and separate tuning controls on the television set. The VHF band is further divided into two frequency ranges: VHF low band (Band I) between 54 and 88 MHz, containing channels 2 through 6, and VHF high band (Band III) between 174 and 216 MHz, containing channels 7 through 13. The wide spacing between these frequency bands is responsible for the complicated design of rooftop TV antennas. The UHF band has higher noise and greater attenuation, so higher gain antennas are often required for UHF.

Terrestrial television

History

The VHF band plan was modified several times before 1948. The last of these changes was the deletion of channel 1, originally intended as a community channel. This allocation of the spectrum was given to two-way land-mobile radio.[1]

UHF channels 70–83 in the United States were reallocated in 1983.

In March 2008, the FCC requested public comment on turning the bandwidth currently occupied by analog television channels 5 and 6 (76–88 MHz) over to extending the FM terrestrial band when the DTT transition was to be completed in February 2009 (ultimately delayed to June 2009).[2] This proposed allocation would effectively assign frequencies corresponding to the existing Japanese FM radio service (which begins at 76 MHz) for use as an extension to the existing North American FM broadcast band.[3]

700 MHz band

The UHF 700 MHz band comprised the spectrum of UHF channels 52 through 69. Channels 52–69 are no longer available for normal, high-power digital terrestrial television broadcasting in the United States, but some channels are available for use as low-power or translator stations.[4] Wireless microphones and medical telemetry devices shared some of the space on this television band, if transmitting at a very low power. After the migration to digital terrestrial television in 2009, the Federal Communications Commission (FCC) banned all of these from using the 700 MHz band, effective June 12, 2010. The 700 MHz band is now used for public safety communications and wireless broadband providers.[5]

600 MHz band

In 2017 the FCC auctioned off all remaining UHF spectrum including and above UHF channel 38.[6] This required the reconfiguration of channel allotment (known in the terrestrial television industry as the channel "repack"), allowing for higher gain small antennas to cover a smaller frequency range. In April 2017 it was decided that channels 38 to 51 would be deleted, but channel 37 remains reserved. Channel repacking proceeded in 10 phases from September 2018 through July 2020.[7]

Channel frequencies

VHF band

VHF low-band (band I)
(frequencies in MHz)
 Channel  Lower edge  Video carrier  ATSC pilot  Audio carrier  Upper edge 
14445.2544.3149.7550
25455.2554.3159.7560
36061.2560.3165.7566
46667.2566.3171.7572
(Gap in band plan)
57677.2576.3181.7582
68283.2582.3187.7588
VHF high-band (band III)
(frequencies in MHz)
 Channel  Lower edge   Video carrier  ATSC pilot  Audio carrier  Upper edge 
7174175.25174.31179.75180
8180181.25180.31185.75186
9186187.25186.31191.75192
10192193.25192.31197.75198
11198199.25198.31203.75204
12204205.25204.31209.75210
13210211.25210.31215.75216

UHF band

The following table lists terrestrial television channels in the ultra high frequency band as they were allocated in their modern form by the Federal Communications Commission on April 11, 1952. The original allocation included 70 UHF channels (14–83) with 6 MHz separation. In the decades since, many of the channels have been de-allocated and reserved for other purposes. Channels 14–36 are usable UHF channels in the United States after the most recent change was completed in 2020. Formerly allocated channels are indicated with a colored background, and their dispositions are explained in the notes below the table.

UHF band
(frequencies in MHz)
 Channel  Lower edge  Video carrier  ATSC pilot  Audio carrier  Upper edge 
14470471.25470.31475.75476
15476477.25476.31481.75482
16482483.25482.31487.75488
17488489.25488.31493.75494
18494495.25494.31499.75500
19500501.25500.31505.75506
20506507.25506.31511.75512
21512513.25512.31517.75518
22518519.25518.31523.75524
23524525.25524.31529.75530
24530531.25530.31535.75536
25536537.25536.31541.75542
26542543.25542.31547.75548
27548549.25548.31553.75554
28554555.25554.31559.75560
29560561.25560.31565.75566
30566567.25566.31571.75572
31572573.25572.31577.75578
32578579.25578.31583.75584
33584585.25584.31589.75590
34590591.25590.31595.75596
35596597.25596.31601.75602
36602603.25602.31607.75608
37608609.25608.31613.75614
38614615.25614.31619.75620
39620621.25620.31625.75626
40626627.25626.31631.75632
41632633.25632.31637.75638
42638639.25638.31643.75644
43644645.25644.31649.75650
44650651.25650.31655.75656
45656657.25656.31661.75662
46662663.25662.31667.75668
47668669.25668.31673.75674
48674675.25674.31679.75680
49680681.25680.31685.75686
50686687.25686.31691.75692
51692693.25692.31697.75698[8][9]
52698699.25698.31703.75704
53704705.25704.31709.75710
54710711.25710.31715.75716
55716717.25716.31721.75722
56722723.25722.31727.75728
57728729.25728.31733.75734
58734735.25734.31739.75740
59740741.25740.31745.75746
60746747.25746.31751.75752
61752753.25752.31757.75758
62758759.25758.31763.75764
63764765.25764.31769.75770
64770771.25770.31775.75776
65776777.25776.31781.75782
66782783.25782.31787.75788
67788789.25788.31793.75794
68794795.25794.31799.75800
69800801.25800.31805.75806
70806807.25806.31811.75812
71812813.25812.31817.75818
72818819.25818.31823.75824
73824825.25824.31829.75830
74830831.25830.31835.75836
75836837.25836.31841.75842
76842843.25842.31847.75848
77848849.25848.31853.75854
78854855.25854.31859.75860
79860861.25860.31865.75866
80866867.25866.31871.75872
81872873.25872.31877.75878
82878879.25878.31883.75884
83884885.25884.31889.75890

Notes

  • Channels 1 and 37 (shaded pink above) are reserved for radio astronomy in the United States, Canada, Bermuda and the Bahamas; thus there are no television stations assigned to it. Mexico, Colombia, Chile, Peru, Brazil and Argentina informally observe a ban on transmitters using the channel. One San Francisco station, KAXT-CD, was assigned Channel 1 as a virtual channel in 2017, but broadcasts on UHF channel 22. One New York City station, WNWT-LD, was assigned Channel 37 as a virtual channel in 2019, but broadcasts on VHF channel 3.
  • Channels 38 through 51 (the 600 MHz band, shaded yellow above) have been displaced in the US by the Broadcast incentive auction.
  • On August 22, 2011, the United States' Federal Communications Commission announced a freeze on all future applications for broadcast stations requesting to use channel 51,[8] to prevent adjacent-channel interference to the A-Block of the 700 MHz band. Later that year (on December 16, 2011), Industry Canada and the CRTC followed suit in placing a moratorium on future television stations using channel 51 for broadcast use for the same reason.[9]
  • Channels 52 through 69 (the 700 MHz band, shaded brown above) in the United States have been reallocated following the conversion to digital TV on June 12, 2009, although some low-power and translator stations may still be in use on these channels.[4]
  • The frequencies used by UHF channels 70 through 83 (shaded blue above) were reallocated to the Land Mobile Radio System (Public Safety and Trunked Radio) and mobile phones in a CCIR worldwide convention in 1983.[4]
  • With the advent of digital television in 2009, stations are allowed to identify themselves by a virtual channel that may not necessarily be the same as the station's RF channel. Virtual channels 1, 37, and 70 to 99 can be assigned via PSIP even though there is no corresponding physical station on that RF channel.[10]
Cable television frequency issues
  • UHF channels 14 to 43 translate to common cable-ready channels 65 to 94 (add 51).
  • UHF channels 44 to 83 translate to rarely used cable TV channels 100 to 139 (add 56).
  • Cable-ready channels 6, 95, 96, and 97 have audio carriers which overlap FM radio stations (87.7, 95.7, 101.7 and 107.7).
  • Cable-ready channels 57 to 61 overlap the 70cm amateur radio band and can be used for amateur television.
  • Cable-ready channel 64 is within the Family Radio Service and General Mobile Radio Service (GMRS) band.
  • Cable-ready channels 95, 96, 97, 22, 23 overlaps with Japanese channels 1, 2, 3, 4, 12.

Historical band plans

VHF low-band (band I & II)
1940 U.S. channel assignments (partly deprecated)
(frequencies in MHz)
 Channel  Lower edge  Video carrier  Audio carrier  Upper edge  Current U.S. use 
15051.2555.7556Amateur band, TV ch. 2
(Break in band plan)
26667.2571.7572TV ch. 4
37273.2577.7578Radio-controlled car/plane hobby, TV ch. 5
47879.2583.7584TV ch. 5
58485.2589.7590TV ch. 6, non-commercial educational FM radio
(Break in band plan)
69697.25101.75102FM broadcasting
7102103.25107.75108
VHF high-band (band III)
1940 U.S. channel assignments (partly deprecated)
(frequencies in MHz)
 Channel  Lower edge  Video carrier  Audio carrier  Upper edge  Current U.S. use 
8162163.25167.75168NOAA Weather Radio (162)
(Break in band plan)
9180181.25185.75186TV ch. 8
10186187.25191.75192TV ch. 9
(Break in band plan)
11204205.25209.75210TV ch. 12
12210211.25215.75216TV ch. 13
(Break in band plan)
13234235.25239.75240Military
14240241.25245.75246
(Break in band plan)
15258259.25263.75264Military
16264265.25269.75270
(Break in band plan)
17282283.25287.75288Military
18288289.25293.75294

Cable television

Harmonically-related carriers (HRC) is a system for assigning television channel numbers to bands of frequencies over a cable television network. William Grant, in his book,[11] states:

"By harmonically relating the carrier frequencies themselves it is … possible to improve system performance. This does not reduce the beats produced, but positions them within the system transmission spectrum, such that they are more tolerable. In effect, all signal carriers are spaced precisely at 6 MHz apart, and thus, all beats generated are at 6 MHz increments. Since the television signals are vestigial sideband modulation, if the beat products can be manipulated to fall on or near the Radio frequency carriers themselves, they are much less offensive."

Incrementally-related carriers (IRC) is a system for assigning television channel numbers to bands of frequencies over a cable television network. The IRC plan attempts to minimize distortion products by deriving all video carrier signals from a common source.[12] The IRC system assigns channel frequencies (for the Pan-American NTSC-M system) spaced 6 MHz apart. In an IRC system, the VHF channels are at their off-air frequencies except for channels 5 and 6, which will be 2 MHz higher than usual.[13]

Both HRC and IRC systems have the added advantage of allowing for one extra channel to be positioned between channels four and five, as the gap between them increases from 4 MHz wide to 6 MHz wide. It is often mapped as channel one or channels 2, 3, and 4 become channels 1, 2, and 3, and the new one becomes channel 5.

Channel frequencies

These frequencies are used for both NTSC-based analog television and QAM-based digital television. Band plans for Pan-American American cable television systems are standardized in EIA standard 542-B.[14]

Channels 57 to 61, and 143 to 145, are used in amateur television.

NOTE: Frequencies given are for luminance carriers. For channel center frequencies, add 1.75 MHz.
Channel numberChannel letterStandard video carrier (MHz)Harmonically-related video carrier (MHz)Incrementally-related video carrier (MHz)QAM / CDSREF carrier (MHz)Audio carrier (MHz)
Subband "T" channels
T-77.256.00037.259.0011.75
T-813.2512.000613.2515.0017.75
T-919.2518.000919.2521.0023.75
T-1025.2524.001225.2527.0029.75
T-1131.2530.001531.2533.0035.75
T-1237.2536.001837.2539.0041.75
T-1343.2542.002143.2545.0047.75
T-1449.2548.002449.2551.0053.75
(Break in band plan)
Lowband
2255.2554.002755.2557.0059.75
3361.2560.003061.2563.0065.75
4467.2566.003367.2569.0071.75
1A-8 (4A or 5A)72.2572.003673.2575.0077.75
55 (or A-7)77.2578.003979.2579.00 or 81.0081.75 or 83.75
66 (or A-6)83.2584.004285.2585.00 or 87.0087.75 or 89.75
Midband
95X or A-591.2590.004591.2593.0095.75
96Y or A-497.2596.004897.2599.00101.75
97Z or A-3103.25102.0051103.25105.00107.75
9800 or A-2109.25108.0054109.25111.00113.75
9901 or A-1115.25114.0057115.25117.00119.75
Midband
14A121.25120.0060121.25123.00125.75
15B127.25126.0063127.25129.00131.75
16C133.25132.0066133.25135.00137.75
17D139.25138.0069139.25141.00143.75
18E145.25144.0072145.25147.00149.75
19F151.25150.0075151.25153.00155.75
20G157.25156.0078157.25159.00161.75
21H163.25162.0081163.25165.00167.75
22I169.25168.0084169.25171.00173.75
Highband
77175.25174.0087175.25177.00179.75
88181.25180.0090181.25183.00185.75
99187.25186.0093187.25189.00191.75
1010193.25192.0096193.25195.00197.75
1111199.25198.0099199.25201.00203.75
1212205.25204.0102205.25207.00209.75
1313211.25210.0105211.25213.00215.75
Superband
23J217.25216.0108217.25219.00221.75
24K223.25222.0111223.25225.00227.75
25L229.25228.0114229.25231.00233.75
26M235.25234.0117235.25237.00239.75
27N241.25240.0120241.25243.00245.75
28O247.25246.0123247.25249.00251.75
29P253.25252.0126253.25255.00257.75
30Q259.25258.0129259.25261.00263.75
31R265.25264.0132265.25267.00269.75
32S271.25270.0135271.25273.00275.75
33T277.25276.0138277.25279.00281.75
34U283.25282.0141283.25285.00287.75
35V289.25288.0144289.25291.00293.75
36W295.25294.0147295.25297.00299.75
Hyperband
37AA or W+1301.25300.0150301.25303.00305.75
38BB or W+2307.25306.0153307.25309.00311.75
39CC or W+3313.25312.0156313.25315.00317.75
40DD or W+4319.25318.0159319.25321.00323.75
41EE or W+5325.25324.0162325.25327.00329.75
42FF or W+6331.25330.0165331.25333.00335.75
43GG or W+7337.25336.0168337.25339.00341.75
44HH or W+8343.25342.0171343.25345.00347.75
45II or W+9349.25348.0174349.25351.00353.75
46JJ or W+10355.25354.0177355.25357.00359.75
47KK or W+11361.25360.0180361.25363.00365.75
48LL or W+12367.25366.0183367.25369.00371.75
49MM or W+13373.25372.0186373.25375.00377.75
50NN or W+14379.25378.0189379.25381.00383.75
51OO or W+15385.25384.0192385.25387.00389.75
52PP or W+16391.25390.0195391.25393.00395.75
53QQ or W+17397.25396.0198397.25399.00401.75
54RR or W+18403.25402.0201403.25405.00407.75
55SS or W+19409.25408.0204409.25411.00413.75
56TT or W+20415.25414.0207415.25417.00419.75
57UU or W+21421.25420.0210421.25423.00425.75
58VV or W+22427.25426.0213427.25429.00431.75
59WW or W+23433.25432.0216433.25435.00437.75
60XX or W+24439.25438.0219439.25441.00443.75
61YY or W+25445.25444.0222445.25447.00449.75
62ZZ or W+26451.25450.0225451.25453.00455.75
63AAA or W+27457.25456.0228457.25459.00461.75
64BBB or W+28463.25462.0231463.25465.00467.75
Ultraband
65CCC or W+29469.25468.0234469.25471.00473.75
66DDD or W+30475.25474.0237475.25477.00479.75
67EEE or W+31481.25480.0240481.25483.00485.75
68FFF or W+32487.25486.0243487.25489.00491.75
69GGG or W+33493.25492.0246493.25495.00497.75
70HHH or W+34499.25498.0249499.25501.00503.75
71III or W+35505.25504.0252505.25507.00509.75
72JJJ or W+36511.25510.0255511.25513.00515.75
73KKK or W+37517.25516.0258517.25519.00521.75
74LLL or W+38523.25522.0261523.25525.00527.75
75MMM or W+39529.25528.0264529.25531.00533.75
76NNN or W+40535.25534.0267535.25537.00539.75
77OOO or W+41541.25540.0270541.25543.00545.75
78PPP or W+42547.25546.0273547.25549.00551.75
79QQQ or W+43553.25552.0276553.25555.00557.75
80RRR or W+44559.25558.0279559.25561.00563.75
81SSS or W+45565.25564.0282565.25567.00569.75
82TTT or W+46571.25570.0285571.25573.00575.75
83UUU or W+47577.25576.0288577.25579.00581.75
84VVV or W+48583.25582.0291583.25585.00587.75
85WWW or W+49589.25588.0294589.25591.00593.75
86XXX or W+50595.25594.0297595.25597.00599.75
87YYY or W+51601.25600.0300601.25603.00605.75
88ZZZ or W+52607.25606.0303607.25609.00611.75
8989 or W+53613.25612.0306613.25615.00617.75
9090 or W+54619.25618.0309619.25621.00623.75
9191 or W+55625.25624.0312625.25627.00629.75
9292 or W+56631.25630.0315631.25633.00635.75
9393 or W+57637.25636.0318637.25639.00641.75
9494 or W+58643.25642.0321643.25645.00647.75
Jumboband
100100 or W+59649.25648.0324649.25651.00653.75
101101 or W+60655.25654.0327655.25657.00659.75
102102 or W+61661.25660.0330661.25663.00665.75
103103 or W+62667.25666.0333667.25669.00671.75
104104 or W+63673.25672.0336673.25675.00677.75
105105 or W+64679.25678.0339679.25681.00683.75
106106 or W+65685.25684.0342685.25687.00689.75
107107 or W+66691.25690.0345691.25693.00695.75
108108 or W+67697.25696.0348697.25699.00701.75
109109 or W+68703.25702.0351703.25705.00707.75
110110 or W+69709.25708.0354709.25711.00713.75
111111 or W+70715.25714.0357715.25717.00719.75
112112 or W+71721.25720.0360721.25723.00725.75
113113 or W+72727.25726.0363727.25729.00731.75
114114 or W+73733.25732.0366733.25735.00737.75
115115 or W+74739.25738.0369739.25741.00743.75
116116 or W+75745.25744.0372745.25747.00749.75
117117 or W+76751.25750.0375751.25753.00755.75
118118 or W+77757.25756.0378757.25759.00761.75
119119 or W+78763.25762.0381763.25765.00767.75
120120 or W+79769.25768.0384769.25771.00773.75
121121 or W+80775.25774.0387775.25777.00779.75
122122 or W+81781.25780.0390781.25783.00785.75
123123 or W+82787.25786.0393787.25789.00791.75
124124 or W+83793.25792.0396793.25795.00797.75
125125 or W+84799.25798.0399799.25801.00803.75
126126 or W+85805.25804.0402805.25807.00809.75
127127 or W+86811.25810.0405811.25813.00815.75
128128 or W+87817.25816.0408817.25819.00821.75
129129 or W+88823.25822.0411823.25825.00827.75
130130 or W+89829.25828.0414829.25831.00833.75
131131 or W+90835.25834.0417835.25837.00839.75
132132 or W+91841.25840.0420841.25843.00845.75
133133 or W+92847.25846.0423847.25849.00851.75
134134 or W+93853.25852.0426853.25855.00857.75
135135 or W+94859.25858.0429859.25861.00863.75
136136 or W+95865.25864.0432865.25867.00869.75
137137 or W+96871.25870.0435871.25873.00875.75
138138 or W+97877.25876.0438877.25879.00881.75
139139 or W+98883.25882.0441883.25885.00887.75
140140 or W+99889.25888.0444889.25891.00893.75
141141 or W+100895.25894.0447895.25897.00899.75
142142 or W+101901.25900.0450901.25903.00905.75
143143 or W+102907.25906.0453907.25909.00911.75
144144 or W+103913.25912.0456913.25915.00917.75
145145 or W+104919.25918.0459919.25921.00923.75
146146 or W+105925.25924.0462925.25927.00929.75
147147 or W+106931.25930.0465931.25933.00935.75
148148 or W+107937.25936.0468937.25939.00941.75
149149 or W+108943.25942.0471943.25945.00947.75
150150 or W+109949.25948.0474949.25951.00953.75
151151 or W+110955.25954.0477955.25957.00959.75
152152 or W+111961.25960.0480961.25963.00965.75
153153 or W+112967.25966.0483967.25969.00971.75
154154 or W+113973.25972.0486973.25975.00977.75
155155 or W+114979.25978.0489979.25981.00983.75
156156 or W+115985.25984.0492985.25987.00989.75
157157 or W+116991.25990.0495991.25993.00995.75
158158 or W+117997.25996.0498997.25999.001001.75

Channel usage

Cable channels 98 and 99 (A2 and A1, 108-120 MHz), if used, have appeared as channel 00 and 01 respectively on some cable boxes.[15]

See also

References

  1. "What Ever Happened to Channel 1".
  2. "In the Matter of Promoting Diversification of Ownership in the Broadcasting Services". Federal Communications Commission. 2008-05-16. Retrieved 2013-07-03. Certain commenters have urged the Commission to give a "hard look" to a proposal that the Commission re-allocate TV Channels 5 and 6 for FM broadcasting 73 FR 28400, 73 FR 28403
  3. Could EXB Band Be Your New Home? Archived 2009-05-06 at the Wayback MachineRadioWorld September 10, 2008
  4. 1 2 3 "FCC Online Table of Frequency Allocations 47 C.F.R. § 2.106" (PDF). Federal Communications Commission. 2016-08-31. Archived from the original (PDF) on 2016-10-30.
  5. "Distribution, Sale and Use of Wireless Microphones Operating in the 700 MHz Band Prohibited". FCC.
  6. McAdams, Deborah D. (29 April 2016). "FCC Releases 126 MHz Clearing Target". TvTechnology.
  7. "600 MHz spectrum - Spectrum Gateway". SpectrumGateway.com. Retrieved 2020-07-19.
  8. 1 2 FCC Public Notice DA-11-1428A1:
  9. 1 2 Government of Canada, Industry Canada (December 30, 2011). "Industry Canada Advisory Letter - Moratorium on the Use of Television Channel 51". IC.gc.ca.
  10. "What Is the Difference Between a RF Channel and a Virtual Channel?". ChannelMaster. Retrieved 2014-12-22.
  11. Cable Television, 2nd edition, GWG Associates, Schoharie, NY, 1988, page 82
  12. Walter S. Ciciora (ed), Modern cable television technology: video, voice, and data communications , Morgan Kaufmann, 2004 ISBN 1-55860-828-1, page 399
  13. "hackerscatalog.com at Directnic". HackersCatalog.com.
  14. Walter S. Ciciora, Modern cable television technology: video, voice, and data communications Morgan Kaufmann, 2004 ISBN 1-55860-828-1, pages 397-402
  15. "Technical Notes". HackersCatalog.com. Extreme Media. 2012. Archived from the original on 2014-07-14. Retrieved 2016-08-12.
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