MFJ MFJ-422D, MFJ-422DX User Manual

MFJ-422D/422DX Instruction Manual

Electronic Keyer Paddle

Introduction

The MFJ-422D Electronic Keyer Paddle is an iambic keyer and paddle combination. The MFJ-422DX keyer installs on your MFJ-564 or Bencher type paddle. Both are microprocessor controlled keyers that provide iambic key operation and dot-and-dash memory to make sending perfect code easier. It has tunable code speed, code weight, and sidetone frequency; it supports both direct and grid-block keying outputs. You also get to choose between Iambic Type "A" and Type "B" keying.

Note: All references to the MFJ-422D apply to the MFJ-422DX, unless otherwise stated.

Control Functions

1.The Power button turns the unit ON and OFF. The power is ON when the button is locked in the "in" position and the LED is lit and OFF in the "out" position.

2.The Semi-Auto/Auto button allows semi-automatic "bug" and manual operations. The keyer generates dots automatically when a squeeze or single lever key is used. Dashes are manually made. The keyer is completely manual when a straight key is used. Semi-Auto is active when the switch is in the "in" position and Auto when in the "out" position.

3.The Speed control, located on the left side of the unit, varies the code speed. The speed range is configured with an internal jumper (JMP9) for 5 to 65 WPM or 10 to 40 WPM. Turn the control clockwise to increase speed and counter-clockwise to decrease speed. The unit is factory set to 5 to 65 WPM. To make the speed adjustment less sensitive, change the speed range to the narrower range of 10 to 40 WPM. To change the speed range the power must be off, then remove the paddle to access the jumper inside the case. Locate jumper JMP9 next to the microprocessor and set it to the "H" position.

Note: Power must be off when changing the jumper settings.

4.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.

5.The Weight control varies the code weight from approximately 25% to 75%, with the standard dot defined as 50% weight. The standard dot-dash-

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MFJ-422/422DX Instruction Manual

Electronic Keyer Paddle

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 flatheaded screwdriver. This control is turned clockwise to increase dot and dash lengths and counter-clockwise to decrease dot and dash lengths.

6.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.

7.The Key Output circuit supports both positive and negative keyed radios. The MFJ-422D 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.

8.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).

Paddle Installation for the MFJ-422DX

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MFJ-422D/422DX Instruction Manual

Electronic Keyer Paddle

If you purchased the MFJ-422DX (keyer without paddle), you must install it onto your paddle. Follow these instructions for installing the MFJ-422DX onto a MFJ-564 or Bencher type paddle:

1.Remove any cables from the paddle. Do not apply power to unit while it is disassembled.

2.Set up your MFJ-422DX now, using the four internal jumpers, to the type of output keying required, the desired Iambic mode, and the speed range. Refer to items 3, 7 and 8 of the previous section for locations and meanings of these jumpers; also, refer to the “Jumper Settings” section on page 5 for the meanings of these jumpers.

3.If you wish to use a nine volt battery, install one now. A nine volt battery fits in the battery clip located inside the case. MFJ suggests the use of a good long-life alkaline battery for longest operation.

4.Remove the rubber foot from the bottom rear of the paddle.

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

6.Slide the MFJ-422DX on to the back of the paddle. Thread the cable through the slot on the bottom of the MFJ-422DX. Secure the case with the rubber foot and new screws. The MFJ-564 Iambic Paddle has four additional holes to better secure the case of the paddle.

7.Connect the BARE wire of the cable to the middle terminal on the bottom of the paddle for GROUND.

8.If you normally operate the paddle right-handed, then connect the DOT (white or clear colored) wire to the left paddle terminal and the DASH (black) wire to the right terminal. Connect the wires the opposite way if you operate the paddle left-handed.

9.Place the cable in the plastic cable clamp and secure it with a screw. Fold any excess cable up into the unit.

Connections

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