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ATV A mateur T ele V ision. Because hams should be seen as well as heard. ATV A mateur T ele V ision. Because hams should be seen as well as heard. What is an ATV signal?. What is an ATV signal?.
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ATVAmateur TeleVision Because hams should be seen as well as heard.
ATVAmateur TeleVision Because hams should be seen as well as heard.
What is an ATV signal? Typically it is an analog NTSC fast scan television transmission identical to the commercial broadcast television system which was recently terminated by the FCC. Recently DTV and HDTV transmitting equipment has begun to appear but still remains too pricey for the average ham radio budget.
What is an ATV signal? What your AM modulator will create. What the TV will “see”.
What you need to get started. Simple to use ATV transmitter from MFJ.
What you need to get started. Complete transceiver from PC Electronics.
What you need to get started. On Screen Display board for call sign overlay.
How far will the signals go? • Typical FM rig outputs 10 watts within a 5 KHz bandwidth giving a power/bandwidth ratio of 10 watts/5 KHz.
How far will the signals go? • Typical FM rig outputs 10 watts within a 5 KHz bandwidth giving a power/bandwidth ratio of 10 watts/5 KHz. • An NTSC video transmitted at 10 watts occupies 6 MHz of bandwidth but expressed in the same terms of power/bandwidth ratio as the FM rig above the video signal is .008 watts/5 KHz.
How far will the signals go? • Typical FM rig outputs 10 watts within a 5 KHz bandwidth giving a power/bandwidth ratio of 10 watts/5 KHz. • An NTSC video transmitted at 10 watts occupies 6 MHz of bandwidth but expressed in the same terms of power/bandwidth ratio as the FM rig above the video signal is .008 watts/5 KHz. • Typical FM rig receiver sensitivity is .2 µV.
How far will the signals go? • Typical FM rig outputs 10 watts within a 5 KHz bandwidth giving a power/bandwidth ratio of 10 watts/5 KHz. • An NTSC video transmitted at 10 watts occupies 6 MHz of bandwidth but expressed in the same terms of power/bandwidth ratio as the FM rig above the video signal is .008 watts/5 KHz. • Typical FM rig receiver sensitivity is .2 µV. • Typical TV receiver sensitivity is 1 µV.
How far will the signals go? • All things considered (sensitivity, bandwidth and noise) the relative difference in signal level required for reception of an FM voice signal vs. reception of a television signal is about 26 dB.
How far will the signals go? • All things considered (sensitivity, bandwidth and noise) the relative difference in signal level required for reception of an FM voice signal vs. reception of a television signal is about 26 dB. • Expressed in simpler terms, to get a useable television signal with identical omni antennas over a distance that can be traversed by a 1 watt FM voice signal would require a television transmitter output of 398 watts.
How far will the signals go? • All things considered (sensitivity, bandwidth and noise) the relative difference in signal level required for reception of an FM voice signal vs. reception of a television signal is about 26 dB. • Expressed in simpler terms, to get a useable television signal with identical omni antennas over a distance that can be traversed by a 1 watt FM voice signal would require a television transmitter output of 398 watts. • Replace your transmit antenna with one that has 13 dB of gain and your TV transmitter requirements now drop to approximately 20 watts.
How far will the signals go? • All things considered (sensitivity, bandwidth and noise) the relative difference in signal level required for reception of an FM voice signal vs. reception of a television signal is about 26 dB. • Expressed in simpler terms, to get a useable television signal with identical omni antennas over a distance that can be traversed by a 1 watt FM voice signal would require a television transmitter output of 398 watts. • Replace your transmit antenna with one that has 13 dB of gain and your TV transmitter requirements now drop to approximately 20 watts. • Make the same improvement to your receive site and the transmitter power drops to about 1 watt. 13dB + 13 dB = 26 dB
How far will the signals go? ATV from KE3GG, 25W PEP, 13dB gain omni antenna @ 30 ft.
How far will the signals go? FM Phone from KE3GG, 25W, 13dB gain omni antenna @ 30 ft.
How can I just watch the action? I’ve heard I can use my old cable ready TV. Is that true?
How can I just watch the action? CATV Ham ATV Channel Frequency 57 421.25 MHz 58 427.25 MHz 59 433.25 MHz 60 439.25 MHz NOTE: The T-MARC band plan only approves the use of 58 and 60.
How can I just watch the action? Cable ready TV
How can I just watch the action? Cable ready TV TV with ATV Downconverter or good quality preamp
How can I just watch the action? $149.95
P3? P5? P2? What’s that? CW RST Readability (1-5), Strength (1-9), Tone (1-9) example: 578 SSB RS Readability (1-5), Strength (1-9) example: 59 FM Q Quality (1-5) example: Q4 ATV P Picture Quality (0-5) example: P3
The P-system. P5 Signal:Noise >45 dB 1000 µV or greater
The P-system. P4 Signal:Noise 35-45 dB 200 µV – 1000 µV
The P-system. P3 Signal:Noise 20-35 dB 50 µV – 200 µV
The P-system. P2 Signal:Noise 8-20 dB 15 µV – 50 µV
The P-system. P1 Signal:Noise 3-8 dB 5 µV – 15 µV
The P-system. P0 Signal:Noise < 3 dB < 5 µV
What use does ATV have? ATV can be used to share visual information with fellow club members such as equipment demonstrations, training videos, and special presentations.
What use does ATV have? ATV can be used to share visual information with fellow club members such as equipment demonstrations, training videos, and special presentations. ATV can be used in conjunction with other modes in support of public service events such as parades, walk-a-thons, or times of emergency.
What use does ATV have? ATV can be used to share visual information with fellow club members such as equipment demonstrations, training videos, and special presentations. ATV can be used in conjunction with other modes in support of public service events such as parades, walk-a-thons, or times of emergency. ATV can be used for ham radio displays and demonstrations to the public, Scouting groups, schools, and government officials.
What use does ATV have? ATV can be used to share visual information with fellow club members such as equipment demonstrations, training videos, and special presentations. ATV can be used in conjunction with other modes in support of public service events such as parades, walk-a-thons, or times of emergency. ATV can be used for ham radio displays and demonstrations to the public, Scouting groups, schools, and government officials. ATV can be used for two-way, face-to-face conversations.
Let’s watch some TV. MoD12ATV.avi
Where can I learn more? No longer in print but can still be found online and occasionally at hamfests.
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