ARRL

3.5MHz Reference Circuit

High End 75 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)

3.75-4.0

Channel Spacing

Random

Information Rate

speech

Emission Type(s)

2K50J3E

Transmitter Power (dBW)

31.7

Transmission Line Loss (dB)

Transmit: .2                   Receive: 0.2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

12

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

43.5

Receiver IF Bandwidth

2500 Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-135

Receiver Signal-to-Noise Ratio (dB)

+6

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

To be determined

Availability Target %

 

Maximum Path Length (km)

 

 

 

3 element yagi--K3ZO and others. Vertical polarization is sometimes preferred for distant contacts, trading off a lower ERP for a  more suitable radiation pattern.

 

Typical 75M SSB contest station

 

 

Characteristics

 

Values

Frequency Band (MHz)

3.75-4.0

Channel Spacing

Random

Information Rate

speech

Emission Type(s)

2K50J3E

Transmitter Power (dBW)

31.7

Transmission Line Loss (dB)

Transmit: .2                    Receive: 0.2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

8

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

39.5

Receiver IF Bandwidth

2500 Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-135 

Receiver Signal-to-Noise Ratio (dB)

+6

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

To be determined

Availability Target %

 

Maximum Path Length (km)

 

 

Full wave horizontal loop at 50 ft.

 

 High End 80M CW contest station

 

Characteristics

 

Values

Frequency Band (MHz)

3.5-3.75

Channel Spacing

Random

Information Rate

10 bit/sec

Emission Type(s)

100HA1A

Transmitter Power (dBW)

31.7

Transmission Line Loss (dB)

Transmit: .2                     Receive: 0.2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

12

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

43.5

Receiver IF Bandwidth

CW:100 Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-149

Receiver Signal-to-Noise Ratio (dB)

+6

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

To be determined

 

 

Maximum Path Length (km)

 

 

 

 

Typical 75 M SSB Amateur Station

 

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

 

Characteristics

 

Values

Frequency Band (MHz)

3.75-4.0

Channel Spacing

Random

Information Rate

Speech

Emission Type(s)

2K50J3E

Transmitter Power (dBW)

31.7

Transmission Line Loss (dB)

Transmit: .2                    Receive: 0.2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

7

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

38.5

Receiver IF Bandwidth

SSB:2500 Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-135

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

 

Dipole at 40 ft

 

Typical 80M CW Amateur Station

 

 

Characteristics

 

Values

Frequency Band (MHz)

3.5-3.75

Channel Spacing

Random

Information Rate

10 bit/s

Emission Type(s)

100HA1A

Transmitter Power (dBW)

20

Transmission Line Loss (dB)

Transmit: .2                   Receive: 0.2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

7

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

26.8

Receiver IF Bandwidth

CW:100Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-149

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 40 ft

 

High End 80 M Digital Amateur Station

 

 

 

Characteristics

 

Values

Frequency Band (MHz)

3.5-3.75

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: .2                  Receive: .2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

8

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

39.5

Receiver IF Bandwidth

500

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-142

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 80M Digital Amateur Station

 

 

Characteristics

 

Values

Frequency Band (MHz)

3.5-3.75

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: .2                   Receive: .2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

7

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

23.8

Receiver IF Bandwidth

500 Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-142

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 80 M SSTV Amateur Station

 

The typical SSTV amateur station exchanges pictures with other stations.

 

Characteristics

 

Values

Frequency Band (MHz)

3.75-4.0

Channel Spacing

Random

Information Rate

.22 to 7.5 frames/sec

Emission Type(s)

2K50J3E

Transmitter Power (dBW)

30

Transmission Line Loss (dB)

Transmit: .2                 Receive: .2

Antenna Polarization

Horizontal; Vertical

Antenna Maximum Gain (dBi)

8

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

41.4

Receiver IF Bandwidth

2500

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-145

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 80 M Beacon Amateur Station

N/A--There don’t appear to be any in operation.

 

Typical 80 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)

3.75-4.0

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)

-20

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

-17

Receiver IF Bandwidth

2500 Hz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-135 

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 80M AM station

 

 

Characteristics

 

Values

Frequency Band (MHz)

3.75-4.0

Channel Spacing

Random

Information Rate

Speech

Emission Type(s)

6K0A3E

Transmitter Power (dBW)

31.7

Transmission Line Loss (dB)

Transmit: .2                 Receive: 0.2

Antenna Polarization

Horizontal

Antenna Maximum Gain (dBi)

8

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

39.5

Receiver IF Bandwidth

6 kHz

Receiver Noise Figure (dB)

13

Receiver System Noise (dBW)

-132

Receiver Signal-to-Noise Ratio (dB)

10

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

To be determined

 

 

Maximum Path Length (km)

Depends on propagation mode