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21MHz Reference Circuit

 

High End 15 M SSB contest station

Competitive contest stations use big antennas in an effort to contact even the smallest and most remote stations.

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.2-21.45

 

Channel Spacing

 

Random

 

Information Rate

 

speech

 

Emission Type(s)

 

2K50J3E

 

Transmitter Power (dBW)

 

31.7

 

Transmission Line Loss (dB)

 

Transmit: .6                  Receive: 0.6

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

17

 

Maximum e.i.r.p. (dBW)

 

48.1

 

Receiver IF Bandwidth

 

2500 Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-153

 

Receiver Signal-to-Noise Ratio (dB)

 

+6

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

Availability Target %

 

 

 

Maximum Path Length (km)

 

 

 

 TH7 Stack p. 11-25 of the ARRL Antenna Book, 18th edition.

 

 Typical 15 SSB contest station


Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.2-21.45

 

Channel Spacing

 

Random

 

Information Rate

 

speech

 

Emission Type(s)

 

2K50J3E

 

Transmitter Power (dBW)

 

31.7

 

Transmission Line Loss (dB)

 

Transmit: .7                    Receive: 0.7

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

15

 

Maximum e.i.r.p. (dBW)

 

46.0

 

Receiver IF Bandwidth

 

2500 Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-153 

 

Receiver Signal-to-Noise Ratio (dB)

 

+6

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

Availability Target %

 

 

 

Maximum Path Length (km)

 

 

 

 

 

Shortened two element yagis are quite popular.

 

 

 High End 15 CW contest station

 

 

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.0-21.2

 

Channel Spacing

 

Random

 

Information Rate

 

10 bit/sec

 

Emission Type(s)

 

100HA1A

 

Transmitter Power (dBW)

 

31.7

 

Transmission Line Loss (dB)

 

Transmit: .6                     Receive: 0.6

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

17

 

Maximum e.i.r.p. (dBW)

 

48.1

 

Receiver IF Bandwidth

 

CW:100 Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-167

 

Receiver Signal-to-Noise Ratio (dB)

 

+1

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

 

 

 Typical 15 M SSB Amateur Station

 

 

 The typical SSB amateur station communicates with other SSB using F layer propagation.

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

7.0-7.3 Receive, 7.075-7.1 and 7.15-7.3 Transmit

 

Channel Spacing

 

Random

 

Information Rate

 

Speech

 

Emission Type(s)

 

2K50J3E

 

Transmitter Power (dBW)

 

31.7

 

Transmission Line Loss (dB)

 

Transmit: ..7                   Receive: 0.7

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

15

 

Maximum e.i.r.p. (dBW)

 

46

 

Receiver IF Bandwidth

 

SSB:2500 Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-153

 

Receiver Signal-to-Noise Ratio (dB)

 

+6

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

Depends on propagation mode

 

Typical 15 M CW Amateur Station

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.0-21.2

 

Channel Spacing

 

Random

 

Information Rate

 

10 bit/s

 

Emission Type(s)

 

100HA1A

 

Transmitter Power (dBW)

 

20

 

Transmission Line Loss (dB)

 

Transmit: .7                   Receive: 0.7

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

8

 

Maximum e.i.r.p. (dBW)

 

27.3

 

Receiver IF Bandwidth

 

CW:100Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-167

 

Receiver Signal-to-Noise Ratio (dB)

 

+1

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

Depends on propgation mode

 

 Dipole at 30 ft

 High End 15 M Digital Amateur Station

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.0-21.2

 

Channel Spacing

 

Random

 

Information Rate

 

45-300 bit/sec

 

Emission Type(s)

 

Many different types

 

Transmitter Power (dBW)

 

31.7

 

Transmission Line Loss (dB)

 

Transmit: .7                Receive: .7

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

15

 

Maximum e.i.r.p. (dBW)

 

46

 

Receiver IF Bandwidth

 

500

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-160

 

Receiver Signal-to-Noise Ratio (dB)

 

+3

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

Depends on the propagation mode

 

 Typical 15 M Digital Amateur Station

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.0-21.2

 

Channel Spacing

 

Random

 

Information Rate

 

45-300 bit/sec, 0-300 bit/sec worst case

 

Emission Type(s)

 

Many different types

 

Transmitter Power (dBW)

 

17

 

Transmission Line Loss (dB)

 

Transmit: .7                  Receive: .7

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

8

 

Maximum e.i.r.p. (dBW)

 

24.3

 

Receiver IF Bandwidth

 

500 Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-160

 

Receiver Signal-to-Noise Ratio (dB)

 

+3

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

Depends on propagation mode

 

 Typical 15 M SSTV Amateur Station

 

 

 The typical SSTV amateur station exchanges pictures with other stations.

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.2-21.45

 

Channel Spacing

 

Random

 

Information Rate

 

.22 to 7.5 frames/sec

 

Emission Type(s)

 

2K50J3E

 

Transmitter Power (dBW)

 

30

 

Transmission Line Loss (dB)

 

Transmit: .7                Receive: .7

 

Antenna Polarization

 

Horizontal; Vertical

 

Antenna Maximum Gain (dBi)

 

12

 

Maximum e.i.r.p. (dBW)

 

41.3

 

Receiver IF Bandwidth

 

2500

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-153

 

Receiver Signal-to-Noise Ratio (dB)

 

+30

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

Depends on propagation mode

 

 Typical 15 M Beacon Amateur Station

 

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.15

 

Channel Spacing

 

N/A

 

Information Rate

 

10 bit/s

 

Emission Type(s)

 

50HA1A

 

Transmitter Power (dBW)

 

20

 

Transmission Line Loss (dB)

 

Transmit:.7

 

Antenna Polarization

 

Vertical

 

Antenna Maximum Gain (dBi)

 

0

 

Maximum e.i.r.p. (dBW)

 

19.3

 

Receiver IF Bandwidth

 

100 Hz

 

Receiver Noise Figure (dB)

 

13

 

Receiver System Noise (dBW)

 

-167

 

Receiver Signal-to-Noise Ratio (dB)

 

+1

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

depends on propagation mode

 

Typical 15 M Hand-Held Amateur Station

 

 

The typical SSB hand-held amateur station can communicate with some other SSB voice amateur stations.

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.2-21.45

 

Channel Spacing

 

Random

 

Information Rate

 

speech

 

Emission Type(s)

 

2K50J3E

 

Transmitter Power (dBW)

 

3

 

Transmission Line Loss (dB)

 

Transmit: .0                   Receive: 00

 

Antenna Polarization

 

Vertical

 

Antenna Maximum Gain (dBi)

 

-5

 

Maximum e.i.r.p. (dBW)

 

-2

 

Receiver IF Bandwidth

 

2500 Hz

 

Receiver Noise Figure (dB)

 

7

 

Receiver System Noise (dBW)

 

-155

 

Receiver Signal-to-Noise Ratio (dB)

 

+6

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

Availability Target %

 

 

 

Maximum Path Length (km)

 

 

 

 Mizuho sell these little radios.

 

 Typical 15 M Satellite Uplink

 

 

Characteristics

 

 

 

Values

 

Frequency Band (MHz)

 

21.0-21.45

 

Channel Spacing

 

Random

 

Information Rate

 

10 bit/s

 

Emission Type(s)

 

100HA1A; 2K50J3E

 

Transmitter Power (dBW)

 

14

 

Transmission Line Loss (dB)

 

Transmit:.0.7

 

Antenna Polarization

 

linear, circular

 

Antenna Maximum Gain (dBi)

 

8

 

Maximum e.i.r.p. (dBW)

 

21.3

 

Receiver IF Bandwidth

 

100 Hz

 

Receiver Noise Figure (dB)

 

7

 

Receiver System Noise (dBW)

 

-152,-138

 

Receiver Signal-to-Noise Ratio (dB)

 

+1;+6

 

Maximum Long-Term Interference Power [dB(W/Hz)]       

 

To be determined

 

 

 

 

 

Maximum Path Length (km)

 

depends on propagation mode

 

 

 

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