MFJ hamProAudio MFJ-654, Инструкция по эксплуатации

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J-654 hamProAudio
TM
Microphone Equalizer/Conditioner Instruction & Technical Manual
-22-
EASY-START INSTRUCTIONS
There are eight frequency boost (increase in amplitude) and cut (decrease in
amplitude) knobs spaced an octave apart in frequency. The center frequencies
are approximately 50, 100, 200, 400, 800, 1600 and 3200 Hz with an additional
½ octave center frequency at 2400 Hz. With a knob set at 12 o’clock there is no
boost or. Cut. Turning the knob clockwise boosts an octave of frequencies by up
to 16 dB while counterclockwise rotation give up to 16 dB of cut.
Adjusting your Transmit Audio Equalizer is based on three principles:
First, reduce your speech energy below 500 Hz. These frequencies contribute
only 4% of intelligibility but has 55% of the speech energy. Do this by turning the
50, 100, 200 and 400 Hz knobs fully counterclockwise. This will drastically
reduce your speech in these two octaves. You may need to increase the
amplitude in this range a little by rotating the 400 Hz knob to 9 to 12 o’clock. Use
the bypass switch to compare. Always adjust the output level to maintain proper
output to your radio.
Second,
increase your speech energy above 1000 Hz. These frequencies
contribute 48 % of intelligibility but only have 4 % of speech energy. Do this by
turning the 800, 1600, 2400 and 3200 knobs fully clockwise. You may need to
decrease the 800 Hz center frequency. Always adjust the output level control so
you don’t overdrive your radio. Use the bypass switch to compare.
Third,
your voice characteristics are unique. Experiment by boosting and
cutting each frequency range based on the two principles above until your find
the right combination that gives
your best speech characteristics
Remember – 12 o’clock is flat (no boost or cut), clockwise is boost and
counterclockwise is cut.
Don’t forget to use the bypass switch often to make comparisons.
You are now set to use the MFJ-654 on the air. It will take some to get familiar
with the amount of Compression that you need as it is always a trade off between
fidelity and the use of Compression to get that rare DX station you have been
after.
TECHNICAL ASSISTANCE