MFJ-422E/422EX Instruction Manual
Electronic Keyer Paddle
2
5.
The
Volume
control, located on the left side of the unit, adjusts the sidetone
level of the internal speaker. Turn the control clockwise to increase the
volume and counter-clockwise to decrease the volume.
6. The
Weight
control varies the code weight from approximately 25% to
75%, with the standard dot defined as 50% weight. The standard dot-dash-
space ratio is 1:3:1 (trimpot at mid-range). This control is accessed through
a small hole on the rear of the unit and may be adjusted using a small flat-
headed screwdriver. This control is turned clockwise to increase dot and
dash lengths and counter-clockwise to decrease dot and dash lengths.
7. The
Tone
control sets the desired sidetone pitch from approximately 300 to
1200 Hz. This control is also accessed through a small hole on the rear of
the unit and may be adjusted using a small flat-headed screwdriver. This
control is turned clockwise to raise the pitch and counter-clockwise to
lower the pitch.
8. The
Key Output
circuit supports both positive and negative keyed radios.
The MFJ-422E can only key one type of transmitter at a time. This is an
internal jumper selected option. The unit is factory set to direct keying
(most solid state radios). To change to grid-block keying (most radios with
tube finals) the power must be off, then remove the paddle to access the
jumpers inside the case. Locate jumpers JMP1 and JMP2. JMP2 is directly
behind the RCA jack (J2). JMP1 is located behind the power jack (J1). Set
both
jumpers JMP1 and JMP2 to the "G" position. To key a solid state
transmitter, set both jumpers to the "D" position.
Note: Power must be off when changing the jumper settings.
9. The
Iambic Type A/B
mode is also set inside the unit with a jumper. The
unit is factory set for Type "A" Iambic. If you prefer Type "B" Iambic,
remove the paddle to access the jumper. Locate jumper JMP3 behind the
power jack (J1), between JMP1 and JMP8; set it to the "B" position. For
Type "A" Iambic, set the jumper to the "A" position.
Note: Power must be off when changing the jumper settings.
When a squeeze is released during an element (dot or dash), type "B" adds
the opposite element. Type "A" just finishes the element in progress and
does
not
produce a following alternate element. For example, in Type "A"
Iambic, a squeeze release during the "dah" in the letter A will produce "dit
dah" (A). In Type "B" Iambic, a squeeze release during the "dah" in the
letter A will produce "dit dah dit" (R).