MFJ-1026 Instruction Manual
Deluxe Noise Canceling Signal Enhancer
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12. Try peaking a signal. The strongest peak will usually be very near the setting of the PHASE control
that produces the deepest null for the same signal, but the PHASE switch will be in the opposite
position from the null position. When peaking a signal, never adjust gain setting. Adjust the
PHASE control and PHASE switch only.
13. After gaining experience on strong steady signals, practice nulling background noise or unwanted
signals.
Remember, you can only null a signal or noise if it is present on
both
the noise and main antennas.
Fading may make it difficult to obtaining a complete null on skywave signals. The most consistent null
will occur if the antennas are moderately close together (between 1/2 and 1/8 wl apart), oriented in the
same direction, and sharing the same polarization.
This device contains a circuit that automatically disables it when transmitting. The T/R DELAY control
will adjust the recovery time of this circuit. If the unit is off, or if the T/R CONTROL line is grounded,
the MAIN ANTENNA port is directly connected to the RADIO port.
WARNING: When transmitting with high power and using external antennas located close
together, excessive RF may illuminate or burn out the fuse lamp at the AUXILIARY
ANTENNA connector. This bulb is rated at 50 mA of current. Never replace this
bulb with higher current bulbs. If fuse lamp burn out is a problem, the antennas
must be moved further apart or an external relay must be used to disconnect the
auxiliary antenna while transmitting.
Other Applications
Since this unit is really an adjustable phasing network that combines two antennas to give various
directional patterns, it can improve receiving signal levels even in the absence of strong noise. For
example:
1. Two parallel Beverage antennas spaced an eighth to quarter wave apart with an eighth to quarter
wave stagger in the desired direction can be combined to improve front to back, steer nulls, or add
desired signals.
2. Two verticals or dipoles can be combined producing a steerable array capable of peaking or nulling
signals.
3. A Beverage and a quiet main transmitting antenna can be combined to enhance weak signals.
Many other combinations are possible. The best system is found by experimentation.