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MFJ-752D SIGNAL ENHANCER II
INTRODUCTION
The improved MFJ-752D SIGNAL ENHANCER II is comprised of two tunable
audio filtering systems designed to clarity and remove interfering signals from both
voice (SSB or AM) and code (CW or RTTY) signals. This is accomplished by a primary
filter which is a two-section, four-pole variable filter which has PEAK, NOTCH, LOW
PASS, and HIGH PASS functions, and by an auxiliary filter which is a single section two
pole PEAK or NOTCH filter. These two independent filters allow you to remove
interference while enhancing the desired signal.
INSTALLATION
1.
Connect any 9-18V DC supply to the power jack on the back of the MFJ-752D. The
adapter must have a 2.1 mm coaxial plug with the center pin position and the sleeve
ground. An optional AC adapter, MFJ-1312B, 9-18VDC adapter is available from
MFJ. A 12 VDC, 300mA supply is required to obtain the full two watts audio output.
2.
Using the proper connector, connect a shielded cable from the external speaker or
headphone jack of the transceiver or receiver to the MFJ-752D. Use an RCA phono
plug to connect to the filter input. There are two inputs on the MFJ-752D allowing
connection to two receivers for greater convenience. The input is selected by the
push button switch on the back of the MFJ-752D.
3.
Connect a speaker to the filter using shielded wire with a RCA phono plug at the filter
speaker output. For best results, use a 4 to 16 ohm speaker.
4.
Headphone operation is accomplished by plugging headphones into the phone jack
on the back of the MFJ-752D. A mono plug or a stereo plug will work for headphone
operation. Plugging in headphones will not mute the speaker jack.
FRONT PANEL CONTROLS
POWER SWITCH:
Selects power OFF, power ON, SSB Noise Limiter and CW Noise
Limiter. The filter is bypassed on the OFF position. NOTE: The
noise limiter in not ON when the power switch is in the ON position.
PRIMARY FILTER:
Function Selector: Selects PEAK, NOTCH, LOW PASS (LP), or HIGH PASS (HP) in
the primary filter.
Selectivity Control: Adjusts the bandwidth of the primary filter from 40 Hz to almost flat.
Frequency Control: Adjusts the center frequency of the peak, notch and the cutoff
frequency of the LOW PASS and HIGH PASS circuits
approximately 300 Hz to 3000 Hz.
Содержание MFJ-752D
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