MFJ MFJ-1046 User Manual

MFJ-1046 Instruction Manual Passive Preselector

MFJ-1046 PASSIVE PRESELECTOR

Introduction

The MFJ-1046 Passive Preselector is designed to reduce receive overload from
strong out of band signals. It contains selective circuits that cover 1.6 to 33
MHz in six steps, providing the greatest selectivity on the lowest frequencies
where overload is most common.

The MFJ-1046 has two rear panel SO-239 connectors for RF connections and a
bypass switch to take the unit in and out of the circuit.

Installation

Connect the MFJ-1046 Passive Preselector between your antenna and receiver as
shown in Figure 1. The Radio connector goes directly to the receiver with a
short well shielded lead; the Antenna connector goes to the antenna.

WARNING:

Figure 1

NEVER connect an am plifier or trans m itter to the MFJ- 1046

Passive Preselector. Failure to follow this warning may
cause MFJ-1046 Passive Preselec tor or other equipment to
be damaged.

1

MFJ-1046 Instruction Manual Passive Preselector

Operation

With the MFJ-1046 Passive Preselector properly connected, simply turn the
Band switch to the desired band and adjust the Tune control for maximum
signal level. With the Bypass switch depressed, the MFJ-1046 Passive
Preselector becomes active.

Adjust t he Tune cont rol fo r maximum s ignal l evel. The max imum loss on the
desired amateur band is less than 5dB if the correct frequency range is selected.

Note

: Always use the highest fr eque ncy band range that co ver s the de sire d ba nd

for minimum loss.

Typical frequency response is shown in Figure 2.

A: Transmission Loss

Figure 2

2