S DBW to S-Meter Conversion Table in VOACAP
The following table shows how S DBW (median signal power expected at the receiver input terminals) values can be mapped to S-meter readings.
There are a few assumptions: the receiver input impedance is 50 Ohms and the transmission lineloss is minimal. Also we assume that the S-meter is correctly calibrated. In practice, S-meters are mostly imprecise and can only give relative readings.
| S DBW | W (50 Ohm) | dBuV | microvolts | S Meter |
|---|---|---|---|---|
| -43.01 | 5.00E-05 | 93.98 | 50000.000 | S9+60 dB |
| -53.01 | 5.00E-06 | 83.98 | 15811.388 | S9+50 dB |
| -63.01 | 5.00E-07 | 73.98 | 5000.000 | S9+40 dB |
| -73.01 | 5.00E-08 | 63.98 | 1581.139 | S9+30 dB |
| -83.01 | 5.00E-09 | 53.98 | 500.000 | S9+20 dB |
| -93.01 | 5.00E-10 | 43.98 | 158.114 | S9+10 dB |
| -103.01 | 5.00E-11 | 33.98 | 50.000 | S9 |
| -109.03 | 1.25E-11 | 27.96 | 25.000 | S8 |
| -115.05 | 3.13E-12 | 21.94 | 12.500 | S7 |
| -121.07 | 7.81E-13 | 15.92 | 6.250 | S6 |
| -127.09 | 1.95E-13 | 9.90 | 3.125 | S5 |
| -133.11 | 4.88E-14 | 3.88 | 1.563 | S4 |
| -139.13 | 1.22E-14 | -2.14 | 0.781 | S3 |
| -145.15 | 3.05E-15 | -8.16 | 0.391 | S2 |
| -151.18 | 7.63E-16 | -14.19 | 0.195 | S1 |
Thank-you
This table has been refined as per suggestions by Ahti OH2RZ.