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are not directly upgradeable to transmit HD Radio. It is true that older transmitters may lack the transmission purity needed to support HD Radio's digital transmission standard, but more recent transmitters are more likely to be capable of upgrading to transmit HD Radio. CAM-D is said to work with
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and other digital radio services. Since they all require new circuitry, inevitably, the price of manufacture will increase. This price will likely begin to decrease once the technology becomes proven. Since all new broadcast radios are moving to full digital formats that decode with nearly identical
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CAM-D is a system that is applicable to medium wave and possibly shortwave transmission. Since receivers are designed for multiple bands, a receiver that requires a substantially different architecture for CAM-D will require special circuitry that will increase its cost. This is similar to
240:, commonly used in shortwave broadcasting, can use less, the same, or more bandwidth as AM, to provide high quality audio. Digital Radio Mondiale requires digital detection circuitry not present in conventional AM radios to decode programming.
297:. Namely, HD Radio's AM broadcast scheme broadcasts two copies of the program offset by a few seconds, allowing signal to be briefly lost and maintain uninterrupted program audio (for example, driving under an overpass,
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Receivers that could decode CAM-D were not available to the public, and with
Leonard Kahn's death, interest in CAM-D vanished and those stations using it turned it off, not seeing any financial return.
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in urban areas, lightning, switching transients, etc.). . However, in the field, HD Radio, at a distance from the transmitter, is still not immune to the aspects of the AM dial such as those below.
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due to radio frequency noise from man-made and natural sources, such as fluorescent lamps, motors, switches and lightning. Simply adding high frequency information does not produce
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a wider variety of existing transmitters, which is a selling point for smaller broadcasters with limited budgets. The price of the CAM-D hardware is $ 65,600 as of July 1, 2007.
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Special CAM-D receivers provide the benefit of better frequency response and a slow auxiliary data channel for display of station ID, programming titles, etc.
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pulled night broadcasts of their AM HD station's signals. CAM-D does not produce interference on any channels 10 kHz or more from the center frequency.
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that under adequate analog signal conditions may allow AM stations to transmit music and other program content with a more lifelike sound.
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CAM-D is said to add high-frequency program information digitally transmitted and then overlaid onto the existing low- to mid-frequency
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353:) in the long term, the overhead of analog circuitry will cause a cost penalty to implement the technology in future radios.
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KCI (Kahn
Communications, Inc., the company that invented CAM-D) uses as one of its main selling points that some older
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signals on AM, however, use more bandwidth signal wise and often create "hash" on surrounding frequencies, up to 30
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433:"White Paper - The Structure and Generation of Robust Waveforms for AM IN Band On Channel Digital Broadcasting"
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from the center frequency. This interference, which is audible mainly on analog radios, was one of the reasons
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A substantial problem of analog AM transmission is that it is subject to poor
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Technical aspects and differences with other digital radio methods
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377:, 1600 AM, Minneapolis, Minnesota, decommissioned April 2, 2021
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Citadel Asks AM Stations To
Suspend Nighttime HD Broadcasts
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RBR Magazine reports on
Leonard Kahn's death June, 2012
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information that AM normally lacks is then transmitted
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407:"Kahn Communications website, accessed 1 July 2007"
49:. Unsourced material may be challenged and removed.
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8:
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463:Lightning and HD Radio Don't Mix - YouTube
122:Compatible Amplitude Modulation - Digital
109:Learn how and when to remove this message
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261:Upgradeability of existing transmitters
7:
293:'s AM HD Radio and CAM-D is that of
47:adding citations to reliable sources
365:, 1580 AM, Fort Lauderdale, Florida
188:beyond this. Audio mixing in the
168:information is still used up to a
14:
282:program. This provides enhanced
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289:A significant disparity between
192:then blends them back together.
23:
34:needs additional citations for
978:Error detection and correction
357:Stations broadcasting in CAM-D
1:
1051:Comparison of radio systems
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1024:International broadcasting
993:FM extended band in Brazil
347:Digital Audio Broadcasting
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878:
252:Availability of Receivers
16:Proposed AM radio format
1003:Shortwave relay station
902:Audio signal processing
897:Audio data compression
351:Digital Radio Mondiale
322:Citadel Communications
238:Digital Radio Mondiale
998:Multipath propagation
821:MPEG-1 Audio Layer II
691:Frequency allocations
566:Frequency allocations
306:signal-to-noise ratio
951:Technical (emission)
178:amplitude modulation
43:improve this article
1081:CAM-D-enabled radio
345:(in digital mode),
199:technologies like
151:in-band on-channel
141:broadcast engineer
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983:FM broadcast band
890:Technical (audio)
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413:on 23 August 2007
224:adjacent channels
149:The system is an
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1045:Radio portal
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1019:History of radio
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137:AM broadcasting
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445:on 2012-02-06
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209:transmissions
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195:Unlike other
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99:February 2008
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60: –
59:
55:
54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
1036:
642:
520:broadcasting
469:
458:
447:. Retrieved
440:the original
427:
415:. Retrieved
411:the original
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303:
288:
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267:transmitters
264:
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242:
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220:interference
213:multichannel
194:
172:of about 7.5
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105:
96:
86:
79:
72:
65:
53:
41:Please help
36:verification
33:
968:Cable radio
911:Technical (
671:DVB-T2 Lite
527:Terrestrial
232:proprietary
135:format for
1070:Categories
850:DirectBand
836:Subcarrier
538:modulation
449:2007-07-01
382:References
333:hardware (
228:Compatible
216:capability
211:, nor any
160:of any AM
154:technology
69:newspapers
913:AM stereo
772:Sirius XM
765:providers
684:Satellite
299:multipath
186:digitally
158:sidebands
1012:Cultural
942:Magnavox
915:formats)
865:SCA/SCMO
860:RDS/RBDS
663:HD Radio
653:DRM/DRM+
648:DAB/DAB+
343:HD Radio
330:HD Radio
314:HD Radio
291:Ibiquity
284:fidelity
234:nature.
205:HD Radio
201:iBiquity
190:receiver
170:bandpass
838:signals
806:AMR-WB+
658:FMeXtra
83:scholar
58:"CAM-D"
932:Harris
927:C-QUAM
816:HE-AAC
793:Codecs
777:Canada
743:DVB-SH
717:S band
712:L band
698:C band
622:L band
513:Analog
417:1 July
339:Sirius
280:analog
247:Issues
182:treble
166:Analog
130:hybrid
85:
78:
71:
64:
56:
922:Belar
748:S-DMB
738:DAB-S
643:CAM-D
556:COFDM
535:Radio
443:(PDF)
436:(PDF)
128:is a
126:CAM-D
90:JSTOR
76:books
870:DARC
845:AMSS
826:DRA+
707:band
616:high
515:and
419:2007
375:KPNP
369:WKBF
363:WSRF
197:IBOC
62:news
855:PAD
811:HDC
801:AAC
753:SDR
733:ADR
667:CDR
626:UHF
612:mid
608:low
604:VHF
318:kHz
222:to
203:'s
174:kHz
164:.
124:or
45:by
1072::
614:/
610:/
598:HF
594:SW
588:MF
584:MW
578:LF
574:LW
551:FM
546:AM
349:,
341:,
337:,
335:XM
312:.
146:.
705:u
703:K
628:)
624:(
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596:(
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586:(
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576:(
505:e
498:t
491:v
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106:(
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97:(
87:·
80:·
73:·
66:·
39:.
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