This required viewers to purchase multistandard receivers though.

Before the All-Channel Receiver Act of 1962 required US television receivers to be able to tune the entire VHF and UHF range ( which in North America was NTSC-M channels 2 through 83 on 54 to 890 MHz ), a set-top box known as a UHF converter would be installed at the receiver to shift a portion of the UHF-TV spectrum onto low-VHF channels for viewing.

Superheterodyne receivers require a local oscillator and mixer, which required two tubes.

This Act required all analog television receivers with screens of at least 13 inches or greater, either sold or manufactured, to have the ability to display closed captioning by July 1, 1993.

* At a receiver facility, the power required for all receivers and auxiliary equipment that may be operated on prime or spare antennas simultaneously, those in standby condition, multicouplers, control and keying equipment, plus lighting, ventilation, and air conditioning equipment required for full continuity of communications.

Multiple receivers are typically required for surveillance of the entire spectrum, but tactical receivers may be functional within a specific signal strength threshold of a smaller frequency range.

However, this was expensive in the early days of computing, since each computer ( except for the ones at each end ) required two receivers and two transmitters.

RF signal generators are required for servicing and setting up analog radio receivers, and are used for professional RF applications.

The approximate impedance required to match a centre-fed dipole antenna in free space ( i. e., a dipole without ground reflections ) is 73 Ω, so 75 Ω coax was commonly used for connecting shortwave antennas to receivers.

Special receivers are required to decode these broadcasts.

The early car radio receivers used the battery voltage ( 6. 3 volts at the time ) to run the vacuum tube filaments, and generated the required high voltage for the plate supply using a vibrator to drive a step-up transformer.

To deduce the range or velocity of a target relative to a multistatic system, knowledge of the spatial location of transmitters and receivers is required.

North Korea restricts most people to a single fixed frequency mediumwave receiver ; those who met political requirements and whose work absolutely required familiarity with events abroad were allowed shortwave receivers.

Some television receivers sold before the HD launch claimed to be " HD-ready ", but this usually implies that the screen can display HD, rather than that DVB-T2 signals can be received — a suitable tuner ( typically built into a STB or PVR ) is additionally required.

As VOR required two VHF receivers as well as a conventional radio for station identification, the system did not become popular until the era of miniaturized electronics, first with small tubes in the 1950s, and then transistorized systems in the 1960s.

After approximately 2, 000 FG42s had been produced by Krieghoff, supplies of the manganese steel from which the receivers were forged were diverted to other needs ; this meant a redesign was required to use stamped sheet metal in its place.

Therefore the TRF receivers used before regenerative receivers often required 5 or 6 tubes, each stage requiring tuned circuits that had to be tuned in tandem to bring in stations, making the receiver cumbersome, power hungry, and hard to adjust.

This narrow-band signal has a much greater range than Wi-Fi, so the number of receivers required for the project are far fewer than the number of Wi-Fi access points covering the same area.

The two companies operated through different receivers, each required consumers to purchase a subscription package, and they offered different, exclusive programming.

This system was not very practical, as it required the listener to use two separate receivers.

However, the corollary is that administrative receivers are usually required under applicable legislation to file reports in relation to the period of their receivership.

While an unlicensed satellite dish can often be identified easily, satellite radio receivers are much more compact and can rarely be easily identified, at least not without flagrantly violating provisions against unreasonable search and seizure in the Canadian Charter of Rights and Freedoms.

( t ) he use of two channels, one transmitting the predominating color ( signal T ), and the other the mean brilliance ( signal t ) output from a single television transmitter to be received not only by color television receivers provided with the necessary more expensive equipment, but also by the ordinary type of television receiver which is more numerous and less expensive and which reproduces the pictures in black and white only.

In addition to Egyptian programming, the Middle East Broadcast Company, a Saudi television station transmitting from London ( MBC ), Arab Radio and Television ( ART ), Al-Jazeera television, and other Gulf stations as well as Western networks such as CNN and BBC, provide access to more international programs to Egyptians who own satellite receivers.

Product mixers can either up-convert or down-convert an input signal frequency, but they are more commonly used to down-convert to a lower frequency to allow for simpler filter designs, as done in superheterodyne receivers.

In many leagues eligible receivers must wear certain uniform numbers, so that the officials can more easily distinguish between eligible and ineligible receivers.

The discovery and development of the technology made radio receivers, then the primary communications devices of the time, more sensitive and selective.

A more controversial version of paperless caching involves mass-downloading only the coordinates and cache names ( or waypoint IDs ) for hundreds of caches into older receivers.

The modernization programme also contains standardized features that allow GPS III and Galileo systems to inter-operate, allowing receivers to be developed to utilise GPS and Galileo together to create an even more precise GNSS system.

Fleming's diode was used in radio receivers and radars for many decades afterwards, until it was superseded by solid state electronic technology more than 50 years later.

RCA antique radios and RCA Merrill / CT-100s and other early color television receivers are among the more sought-after collectible radios and televisions, thanks to their popularity during the golden age of radio, their manufacturing quality, their engineering innovations, their styling and their name, RCA.

By 1987 there were approximately 42 million radio receivers in use, and more than 100 radio stations were broadcasting.

However, modern integrated-circuit digital signal processing ( DSP ) technology could be used to build autocorrelation receivers to check far more channels.

For early domestic radios, tuned radio frequency receivers (" TRF "), also called the Neutrodyne, were more popular because they were cheaper, easier for a non-technical owner to use, and less costly to operate.

Usually the intermediate frequency is lower than the reception frequency f < small >< sub > d </ sub ></ small >, but in some modern receivers ( e. g. scanners and spectrum analyzers ) it is more convenient to first convert an entire band to a much higher intermediate frequency ; this eliminates the problem of image rejection.

In a one-way time transfer system, one end transmits its current time over some communication channel to one or more receivers.

The introduction of the miniature tube base ( see below ) which could have 9 pins, more than previously available, allowed other multi-section tubes to be introduced, such as the 6GH8 / ECF82 triode-pentode, quite popular in television receivers.

After World War I, specialized manufacturers using more economical construction methods were set up to fill the growing demand for broadcast receivers.

Multimeters were invented in the early 1920s as radio receivers and other vacuum tube electronic devices became more common.

The engineering penalty that is paid is that QPSK transmitters and receivers are more complicated than the ones for BPSK.

Where more than one user is on the same channel ( co-channel users ), selective calling addresses a subset of all receivers.

Another drawback is the height of the orbit, usually which requires more powerful transmitters, larger-than-normal ( usually dish ) antennas, and higher-sensitivity receivers on the earth.

As television became the main market, its demand for simultaneous delivery of relatively few signals of large bandwidth to many receivers being a more precise match for the capabilities of geosynchronous comsats.

They do have some drawbacks however: they are slower than more modern boxes with faster processors ( ONdigital receivers often take several seconds to change channel for example ) and lack support for the full Freeview Electronic Programme Guide, as this feature was introduced well after the ONdigital receiver software was written.