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Spectrum Measurements

RF Output Measurements:  

 

a) Spectrum Harmonics:

 

Frequency  MHz

2nd Harmonic dBc

3rd Harmonic dBc

1.9

-70

-81

3.6

-60

-73

5.4

-67

-86

7.15

-64

-82

10.15

-64

-72

14.15

-58

-70

18.15

-66

-80

21.2

-73

-80

24.9

-62

-68

29.7

-60

-60

50.5

-77

-63

70.5

-59

-70

 

b) Carrier Suppression:

 

 

Frequency

Suppression  dBc

1.8 to 30 MHz

-80

50 to 72 MHz

-70

 

c) Inter Modulation Distortion (IMD):

 

Two Tone Test result =   - 40 to - 47 dBc.  Measured at +37 dBm Output

( Measured using HDSDR  Two Tone Generator and a 10 KHz Offset).

See Photo below (e).

 

d) RX Local Oscillator Power, Feed through to Antenna:

 

 

Frequency MHz

LO Pwr. at Antenna (dBm)

LNA selected

1.8

-80

-

3.5

-83

-

5.398

-80

-

7.15

-82.5

-

10.15

-87

-

14.15

-90

-

18.15

-85

-110

21.15

-78

-106

24.95

-77

-99.5

28.5

-74.7

-97.4

50.5

-67

-84.4

70.5

-64.2

-84.9

72.5

-66

-99.6

144

-110

-

432

-102.2

-

1296

-96.6

-

 

e) Power Amplifier  RF Output,  two-tone high linearity performance ( IMD -47.84 dBc) :

 


 

TX RF Output Power

 

Freq MHz                   Power O/P dBm                    PEP Watts

 

1.8                               + 43.83                                  34.14

3.7                               + 43.14                                  29.14

5.4                               + 44.3                                    38.06

7.15                             + 44.1                                    36.33

10.15                           + 44.5                                    39.84

14.15                           + 44.15                                  36.76

18.15                           + 44.0                                    35.51

21.15                           + 43.83                                  34.15

24.9                             + 43.32                                  30.37

28.5                             + 42.8                                    26.9

50.5                             + 43.9                                    34.7

70.5                             + 44.2                                    37.18

 

 

'S' Meter  and  RX Attenuator Accuracy versus Frequency

 

Tested at an RX input power of -73.0 dBm  (S 9)

 

Freq. MHz             S Meter dBm                Atten     -10dB             -20dB             -30dB

 

1.8                          -74.8                                       -84.8               -94.4               -104.4

3.6                          -73.1                                       -82.9               -92.7               -102.7

5.4                          -73.1                                       -83.0               -92.7               -102.7

7.15                        -73.1                                       -83.2               -93.0               -103.0

10.15                      -72.4                                       -82.7               -92.7               -102.5

14.15                      -73.0                                       -82.9               -93.0               -102.9

18.15                      -73.0                                       -83.5               -93.4               -103.2

21.15                      -73.6                                       -83.9               -93.8               -104.3

24.9                        -74.1                                       -84.4               -94.4               -104.3

28.5                        -74.8                                       -85.6               -95.3               -105.2

50.5                        -72.6                                       -83.1               -93.4               -103.0

70.5                        -73.7                                       -83.2               -92.9               -103.2

 

 

Receiver Sensitivity:

 

Minimum Detectable Signal (MDS) in 500 Hz BW for 6dB increase in S+N/N ratio.  (One 'S' Point indicated).

 

Freq. MHz            Signal dBm    V rms (nV).     Pre Amp       Signal dBm            V rms (nV)

 

10.150                  -124.5                133                off                  n/a                       n/a

14.150                  -126.0                112                off                  n/a                       n/a

18.150                  -126.0                112                off                  n/a                       n/a

21.150                  -124.0                141                off                  n/a                       n/a

24.900                  -120.0                223                on                  -121.0                 199

28.500                  -121.0                199                on                  -128.0                   89

50.500                  -118.5                266                on                  -128.3                   86

70.500                  -119.7                235                on                  -125.5                 119