2. The MFJ-484 comes with a 110 volt AC ADAPTER. First plug the ADAPTER into the sub mini-
ature jack on the rear panel and then plug the ADAPTER in the 110 VAC wall socket. It is not
necessary to unplug the AC ADAPTER when the memory keyer is not in use.
3. During portable use when 110 VAC is not available, plug external batteries into the 12–15 VDC
sub miniature jack on the rear panel. External batteries and the AC ADAPTER can be plugged
in at the same time. The external batteries never come into use unless power from the ADAPT-
ER is lost. The tip of the sub miniature plug is positive and the sleeve is ground for external
batteries.
4. A squeeze or single lever key can be used. Squeeze key allows IAMBIC operation. Use a
standard quarter inch stereo phone plug and a two conductor shielded cable or two separately
shielded cables. Tie the shields together and use it for ground. The dot wire should connect to
the ring of the plug, the dash wire to the tip and the shield to the ground.
5. A new reliable solid state keying circuit allows keying of all grid blocks, cathode and solid state
transmitters. For grid block keying use the GRID BLOCK keying output. For cathode keyed
and solid state transmitters use the DIRECT keying output. Try both outputs if you are uncer-
tain as to which output to use. The keyer outputs are self protected. The GRID BLOCK output
keys a maximum negative voltage of 300 volts to ground at 10 ma. The DIRECT output keys a
maximum positive voltage of 300 volts to ground at a maximum current of 100 ma. Use
shielded cable to connect between the memory keyer and the transmitter key input.
OPERATING PROCEDURE
I. KEYER OPERATION
1. Apply power to the memory keyer. Use the AC adapter provided.
2. Plug in key paddle to the KEY jack. A dual paddle squeeze key or a single lever key can be
used.
3. Push TONE, WEIGHT, SPEED and DELAY controls in.
4. Turn VOLUME control clockwise to turn on memory keyer.
5. Start sending with paddle and adjust volume, tone, weight and speed. NOTE: The weight
control may cause a steady tone at high speed, should this occur the weight or the speed
must be reduced by turning the knob counter clockwise.
6. The dot and dash memories ease sending by allowing keying the dot before the completion
of the dash or vice versa. The feature can be checked by setting the lowest speed and tap
first the dash lever then the dot lever before completion of the dash. The keyer will provide
both the dash and the dot. The dash memory can be checked by first tapping the dot then
the dash. The dot insertion features allows you to tap the dot side to insert a dot while hold-
ing the dash side in. The dash insert feature allows you to tap the dash side to insert a dash
while holding the dot side in. When using squeeze key and with both paddles squeezed to-
gether the Iambic operation feature allows sending of alternate dots and dashes. The first
contact determines whether a dot or dash occurs first.
II. MEMORY OPERATION
A. RECORDING
1. Turn the MEMORY SELECT to position 1, 2, 3 or K. Position K will record up to 100
character continuous message.
2. Pull SPEED control out and adjust speed. Press a MEMORY ADDRESS button (A, B, C
or D) and start sending immediately. (NOTE: RECORDING will not start until a MEMO-
RY ADDRESS button is pressed while in the recording mode.) Memory LED will light up
when memory is in operation. Each LED corresponds to the MEMORY button directly
above it. Message including spaces is being recorded as long as the LED is lit in the re-
cording mode. When LED goes out, this indicates the memory is full. If LED goes out
before you have finished sending, the message is too long. Combine memory ad-
dresses A and B by putting the WEIGHT control out to double the memory space. When
recording, the internal clock runs continuously to allow spaces of any length to be en-
