Channel 37

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In countries using the M and N broadcast television system standards, TV channel 37 occupies a band of UHF frequencies from 608 to 614 MHz. In the United States and Canada, channel 37 has never been used by any over-the-air television station, as it was reserved in 1963 for radioastronomy. The United States Federal Communications Commission (FCC) ban on such stations took effect at the beginning of 1974, though it is unclear which stations (if any) were already assigned to use 37.

1 Allocation issues
2 In popular culture
3 Outside the Americas
- 3.1 Global TV allocations table (605-615 MHz)
4 References
5 External links

[edit] Allocation issues

Reservations non-exclusive

The Canadian Radio-television and Telecommunications Commission (CRTC) also enacted such a ban on channel 37.
It appears that Mexico may also observe a similar ban on the use of this TV channel, if only informally.
Most NTSC System-M countries have an informal ban on channel 37 as well.

Since July 2000, channel 37 may also be used in the U.S. for medical telemetry equipment on a co-primary basis. This equipment must emit no more than one watt of effective radiated power, and is for use in hospitals and other such facilities.

The power level permitted by the FCC is many times more than the amount allowed for Part 15 unlicensed broadcasting.

This seemingly low power level can be troublesome for radioastronomy, because it depends on detecting extraordinarily low signal strengths. Any use of the same frequencies raises the noise floor, thereby decreasing the signal-to-noise ratio, and making the work more difficult.

Channel 1 was also removed from the TV bandplan in the late 1940s, channels 70 to 83 by the 1980s mainly for AMPS mobile phones, and soon 52 to 69 for cellular telephones, emergency services and mobile TV services such as Qualcomm's MediaFLO (channel 55). Certain of channels 14 through 20 are used for landmobile communications in some large metro areas in the U.S.

[edit] In popular culture

Channel 37 is sometimes seen in fiction, the same way phone numbers with the "555" telephone exchange prefix are used.

Channel 37 has been used as a hypothetical example in instruction manuals, where it serves a role analogous to the fictitious example.org and example.net Internet domains. ^[1] The "Channel 37" newsroom also occasionally has made a fictional appearance on sites such as YouTube and MySpace.

[edit] Outside the Americas

Outside North America, channel 37 is active: in the Philippines (UNTV Channel 37); in Trinidad and Tobago, WIN-TV is broadcast on Channels 37 and 39, using NTSC; in the UK (many transmitters used by the Five network actually broadcast on channel 37); and in France and Ireland, among other countries. However, frequency allocation for TV channels is different in these countries, and channel 37 is not the same frequency as it is in the countries using the System-M/N standard. At least in the UK, 606–614 MHz is reserved for radio astronomy.

The UK's namesake "Channel 37", while different in frequency, was formerly part of a small group of channels reserved for non-broadcast purposes such as RF modulators in video players. ^[2] The UK-named 34-37 channel range is no longer reserved in this manner.