>With 0db attenuation, take the S meter reading at the adjacent
frequency, tune to the fundamental frequency, add attenuation as needed to give
the same S-meter reading as before. The # of db of attenuation
is how many db down the total IMD is.<
Even this depends on how accurately you can set the S meter to the same place.
If we have a meter range to S9 + 40, and even 4 dB per S point, that's a 76dB
range. So to set to 1dB, you have to get the meter to within around 1.5% of the
same value - and on a speech signal, too.
73
Peter W6/G3RZP
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|