2N5109 RF Amplifier

10MHz 2N5109 Noise Figure Measurement
10MHz 2N2219A Noise Figure Measurement
Common Emitter Transformer Feedback
Push Pull Amplifier


3MHz Noise Figure Measurement
N-Gen -> 40dB Attenuator -> DUT -> 30dB LNA -> VNWA Port 2
Power = 12.0 VDC


DUT NF Measurement


Elecraft N-Gen ENR Measurement
VNWA Spectrum Analyzer Mode
  • VNWA 4000 Points, 400s Sweep, 40kHz bandwidth
  • Rigol DG1032 -31.7dBm + 40dB attenuator Measurement
  • Measurement error = -71.7 - -71.14 = -0.56dB
  • Shape factor noise under response ~ 2.5dB
  • Effective BW = 50kHz
  • N-Gen External Power = 12.0Vdc
  • VNWA N-Gen Measurement = -71.7dBm
  • Measured power = -71.7dBm - 0.56 + 2.5 = -69.76dBm
  • Power with 40dB attenuator -69.76 - 40 = -109.76dBm
  • ENR=10*log(10^((P-30)/10)/(290*k*B)-1) = 17.14dB = 51.79
    P = measured noise power in dBm
    k = 1.38065e-23 Boltzman constant
    B = Bandwidth in Hz
DUT NF Measurement
  • VNWA 801 Points, 30s Sweep, 5kHz bandwidth
  • Tc = -83dBm, Th = -68.9dBm, Delta = 14.1dB
  • Y = 10^(14.1/10) = 25.7
  • NF = ENR/(Y-1) = 51.79/(25.7 - 1) = 2.10 = 3.2dB
LNA+VNWA NF Corrected DUT NF Measurement
  • NF1 = NFnet - (NF2 - 1) / Gain1
  • Gain1 = 17dB = 50
  • NF2 = 3.56 (LNA + VNA below)
  • NFDUT = 2.10 - (3.48 - 1) / 50 = 2.05 = 3.1dB


LNA + VNWA Noise Figure

  • Tc Th Delta = 12dB
  • Y = 15.85
  • NF = 51.79/(15.85 - 1) = 3.49 = 5.4dB



Schematic



Power Input L Filter
27uH with Parallel 0.01uF and 4.7uF Tantalum



High Frequency Compensation

T37-2 17T ~1.2 uH Feedback Inductor



VNWA S11 and S21 Measurement
VNWA Port 1 -> DUT -> 20dB Attenuator -> VNWA Port2



Solderless Breadboard Design