WØINK October 2008 DTV & Radio AmateurPage 1 of 17 DIGITAL TELEVISION an Radio Amateur Perspective by VIRGIL LEENERTS WØINK ARRL Technical Specialist

WØINK October 2008 DTV & Radio AmateurPage 2 of 17 Presentation Topics Short history of TV Channels DTV Channels – pre & post Feb 2009 TV Standards Comparison of ATV & DTV The Over The Air (OTA) viewer. Effects on Amateur Radio

WØINK October 2008 DTV & Radio AmateurPage 3 of 17 Short History of OTA TV Channels 1948 – Channel One (44-50MHz) was removed for business com & 6 M band. 1970s – Channels 70 thru 83 were removed from band plan for cellular telephones – Channels 52 thru 69 were removed from band plan for other purposes – Channels 2 –36 & are allocated for TV. (49 DTV Channels)

WØINK October 2008 DTV & Radio AmateurPage 4 of 17 TV RF Spectrum

WØINK October 2008 DTV & Radio AmateurPage 5 of 17 Additional Channel Notes Ch 37 is allocated to Radio Astronomy. Even though digital TV has been mandated by the FCC, low power TV stations may remain analog.

WØINK October 2008 DTV & Radio AmateurPage 6 of 17 Local OTA DTV Channels LocationA ChD Ch (V Ch)2009 D Ch Denver, CO234 (2)34 Denver, CO435 (4)35 Denver, CO618 (6)18 Denver, CO717 (7)7 Denver, CO916 (9)9

WØINK October 2008 DTV & Radio AmateurPage 7 of 17 Local OTA DTV Channels LocationA ChD Ch (V Ch)2009 D Ch Denver, CO1238 (12)38 Denver, CO3132 (31)32 Cheyenne, WY530 (5)30 Cheyenne, WY2728 (27)27 Laramie, WY88 Analog

WØINK October 2008 DTV & Radio AmateurPage 8 of 17 List of Channels in State Complete list of channels for Colorado and Wyoming can be found by using Google and entering Digital TV Channels, Colorado or Wyoming.

WØINK October 2008 DTV & Radio AmateurPage 9 of 17 Television Standards The analog TV standard ( NTSC ) was developed in 1941 by the National Television Standard Committee and was modified later to include color television. The digital TV standard ( ATSC ) was developed about 2005 by the Advanced Television Systems Committee.

WØINK October 2008 DTV & Radio AmateurPage 10 of 17 ATV Transmission Channel Width – 6 MHz Picture – AM ( VSB – Vestigial sideband – i.e. Lower side band is filtered ) Sound – FM ( 25 KHz )

WØINK October 2008 DTV & Radio AmateurPage 11 of 17 DTV Transmission Channel Width – 6 MHz Picture & Sound – AM ( 8-VSB ) Pilot Carrier ( 310 KHz from lower band edge ) Details in article What Exactly is 8-VSB Anyway? by David Sparano.

WØINK October 2008 DTV & Radio AmateurPage 12 of 17 Analog to Digital Levels

WØINK October 2008 DTV & Radio AmateurPage 13 of 17 RF Spectrum of ATV & DTV

WØINK October 2008 DTV & Radio AmateurPage 14 of 17 DTV Reception Two ways to receive DTV signals. Digital TV Receiver OR Digital TV Tuner connected to an Analog TV Receiver. Also known as a DTV converter which receives DTV signals and converts to composite video. $40 Coupons –

WØINK October 2008 DTV & Radio AmateurPage 15 of 17 The OTA Viewer DTV can have many programs channels for one RF channel. Including HDTV programs. DTV is less susceptible to power line and other pulse noise – clearer picture. DTV is more sensitive than ATV by about 6 to 10 dB. DTV stations can be adjacent to each other.

WØINK October 2008 DTV & Radio AmateurPage 16 of 17 DTV and Amateur Radio Interference to an DTV signal will be difficult for the viewer to discern source. Interference level for DTV & ATV is about the same level relative to signal strength. Locally Ch 2 is moving to Ch 34 (UHF) which is good for 6 meter operators.

WØINK October 2008 DTV & Radio AmateurPage 17 of 17 Conclusion Overall, DTV is a Win-Win DTV better utilizes RF spectrum. DTV transmitters are more efficient. OTA viewers have more program channels. OTA viewers have clearer pictures with better resolution and less interference. Amateurs in CO front range will have less interference issues because lower VHF channels will be vacant of stations.