MFJ MFJ-422B, MFJ-422B-X Owner's Manual

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MFJ-422B/422B-X INSTRUCTIONS

INTRODUCTION

Thank you for your purchase of the MFJ-422B/422B-X Electronic Keyer.
The MFJ-422B/422B-X is designed to mount on the "BENCHER" paddle
resulting in a compact, one-piece Keyer/Paddle combination. The improved
Curtis 8044 ABM Keyer IC is used in the MFJ-422B/422B-X to make perfect
code transmission easy and pleasant. Controls are located for easy
access while operating.

CONTROLS

1. VOLUME: Adjust the volume of the sidetone from the internal speaker.

Functions as the power ON/OFF switch for the MFJ-422B/422B-X.

2. SPEED: Varies the sending speed from 8 to 50 WPM.

3. AUTO/SEMI-AUTO: AUTO-Normal operating position. Dots and dashes of

the correct length are generated automatically.
SEMI-AUTO:-Dots are generated automatically. Dashes are manually
made. (NOTE: In this position, when the dash paddle is held your
transmitter is continuously for tuning.)

4. TONE: Sets the pitch of the sidetones. This control is recessed

inside the cabinet between the VOLUME and SPEED controls. A small
flat head screwdriver is needed for adjustment.

5. WEIGHT: Adjusts dot and dash lengths. When turned fully counter-

clockwise, dot-dash-space ratio is a perfect 1:3:1. This control is
located on the rear of the cabinet and is also recessed. A small flat
head screwdriver is necessary for adjustment. (NOTE: The weight
control is factory set for a 1:3:1 ratio.)

INSTALLATION

FOR MFJ-422B (KEYER WITH PADDLE)

If you purchased the MFJ-422B (Keyer with Paddle), the keyer will
come factory installed on the paddle and the only connections necessary
will be to your transmitter and power supply if used.

If battery operation is desired, remove the rubber foot on the
bottom rear of the paddle and screw holding the plastic wire clamp from
the bottom center of the paddle. The keyer will now slide off the paddle
base toward the rear. Install a 9V transistor battery in the battery
snap and slip the battery into the holder. Reverse the above procedure
to re-install the keyer onto the paddle. Feed the connecting cable
through the slot on the bottom of the paddle and is clamped securely with
the cable clamp. (NOTE: Long-life Alkaline type batteries are recommended
for longest uninterrupted operation.)

FOR MFJ-422B-X (KEYER WITHOUT PADDLE)

If you purchased the MFJ-422B-X (Keyer without Paddle) for
connection to your own "BENCHER" paddle, follow the procedure below for
proper connection.

1. Remove the rubber foot from the bottom rear of your "BENCHER" paddle.

2. Remove the plastic cable clamp from the bottom center of the paddle.

3. Solder the shield on the cable from the MFJ-422B-X to the solder lug

located between the rear rubber foot and the cable clamp on the bottom
of the paddle.