Tagad tikai sapratu ka man ir decibelu mērītājs, tikai kāds!
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| V - spriegums voltos - pV, nV, uV, mV, V, kV, MV I - strāva ampērās - pA, nA, uA, mA, A, kA, MA P - jauda vatos - Wati - pW, nW, uW, mW, W, kW, MW R - pretestība omos - uOmi, mOmi, Omi, kOmi - Kom, MOmi - Mom pΩ, nΩ, uΩ, mΩ, Ω, kΩ, MΩ
U=IR, R=U/I, I=U/R, P=UI
Volti=Ampēra x Oms V=A x Ω, mV=mA x Ω, mV=A x mΩ Wati=Volti x Ampēra W=VA, mW=mV x A, mW=V x mA, uW=mV x mA |
atrodam I=√P/R, tad visu pārējo:
-10db 100uW 600Ω x0,408mA=245mV
0 dBm = 1mW - 600Ω x1,29mA=775mV 775mV x1,29mA =999,75uW =....=1mW
+10dB 10mW 600Ω x4,08mA=2,45V 2,45Vx4,08mA=9,996mW .... 10mW
+12dB 15,85mW 600Ωx5,14mA=3,08V
+12dB 15,85mW 600Ωx5,14mA=3,08V
Vienīgi nevaru saprast tas mēra jaudu dB vai spriegumu dB.
Varbūt abus reizē, bet ... 3V +12dB, ... tā ir rakstīts uz skalas .... laikam ABAS REIZĒ.
Jaudas un sprieguma, un strāvas decibelu (dB) tabula (Decibel table /chart) _dBm dBi dBv table 50ohm
| dB | Power Ratio |
P=Wati +dB__-dB... |
Current or Voltage Ratio |
U=Volti +dB__-dB... |
|---|---|---|---|---|
| 0,000 |
1mW 600Ω | 775mV 600Ω | ||
| 0.1 | 1.023 | 1.023_0,978mW | 1.012 | 784,3_765,8mV |
| 0.2 | 1.047 | 1.023 | 792,8_757,6mV | |
| 0.3 | 1.072 | 1.035 | 802,1_748,8mV | |
| 0.4 | 1.096 | 1.047 | 811,4_740,2mV | |
| 0.5 | 1.122 | 1.059 | 820,7_731,8mV | |
| 0.6 | 1.148 | 1.072 | 830,8_722,9mV | |
| 0.7 | 1.175 | 1.084 | 840,1_714,9mV | |
| 0.8 | 1.202 | 1.096 | 849,4_707,1mV | |
| 0.9 | 1.230 | 1.109 | 859,5_698,8mV | |
| 1.0 | 1.259 | 1.259_0,794mW | 1.122 | 869,55_690,7mV |
| 2.0 | 1.585 | 1.259 | 975,7_615,6mV | |
| 3.0 | 1.995 | 1.413 | 1095_548,5mV | |
| 4.0 | 2.512 | 1.585 | 1228_489mV | |
| 5.0 | 3.162 | 1.778 | 1378_436mV | |
| 6.0 | 3.981 | 1.995 | 1546_388mV | |
| 7.0 | 5.012 | 2.239 | 1,735V_346mV | |
| 8.0 | 6.310 | 2.512 | 1,947V_309mV | |
| 9.0 | 7.943 | 2.818 | 2,184V_275mV | |
| 10 | 10.0 | 10mW_0,1mW | 3.162 | 2,45V__245mV |
| 20 | 10^2 | 100mW_10uW | 10.0 | 7,75V_77,5mV |
| 30 | 10^3 | 1W_1uW | 31.62 | 24,5V_24,5mV |
| 40 | 10^4 | 10W_0,1uW | 100.0 | 77,5V_7,75mV |
| 50 | 10^5 | 100W_10nW | 316.2 | 245V_2,45mV |
| 60 | 10^6 | 1kW_1nW | 1000.0 | 775V_0,775mV |
| 70 | 10^7 | 10kW_0,1nW | 3162.3 | 2,45kV_0,245mV |
| 80 | 10^8 | 100kW_0,01nW | 10000 | 7,75kV_77,5uV |
| 90 | 10^9 | 1MW_1pW | 31623 | 24,5kV_24,5uV |
| 100 | 10^10 | 10MW_0,1pW | 100000 | 77,5kV_7,75uV |
| Piemēri | Piemēri | |||
| 12 |
x10 x1.5... |
10mW x1.585 =15,85mW |
x3.162 x1.259 |
3085mV 3,085V |
| -12 |
/10 /1.5... |
0,1mW /1.585 =0,063mW |
/3.162 /1.259 |
194,7mV 0,195V |
| 39,2 |
1000mW x7.943 x1.047 =8,316W |
x31.62 x2.818 x1.023 |
70,629V | |
| -39,2 |
1uW /7.943 /1.047 =0,12uW |
/31.62 /2.818 /1.023 |
8,4986mV |
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