Vectronics VEC-221K - Manual (Page 23)

VEC-221K Instruction Manual CW Memory Keyer Kit
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Experienced builders may opt to power the VEC-221K from an external power
source. The absolute maximum DC supply voltage is limited to 12 Vdc by the
LM386 specifications. Keyers damaged by over-voltage conditions will not be
honored under the terms of the Warranty.
Keyer paddles: Most popular paddles will work well with the VEC-221K. Full
enjoyment of the VEC-221K’s features requires paddles that are capable of
iambic operation. We recommend the Vectronics iambic paddles as being a
good value. Iambic paddles can be recognized by the totally independent
operation of the Dit (or “Dot”) and Dah (or “Dash”) paddles. Some CW
operators refer to iambic paddles as “squeeze paddles”.
The paddles should be equipped with a three-wire interconnecting cable
terminated in a 3.5 mm stereo jack. Miniature shielded and balanced
microphone cable is ideal for this. The common return is connected to the
longest “ring” (shaft) of the stereo jack. The Dah paddle connection is made to
the jack terminal for the smaller insulated ring. The Dit paddle is connected to
the jack tip connection. If your paddles are equipped with a ¼” stereo jack, a
suitable stereo adapter is available at most electronic or hi-fi shops. Reversed
paddle wiring can be corrected by a function entry, more on this later. The
paddles are connected to J1 on the VEC-221K.
Tip (dit)
Ring (dah)
Common
3.5mm stereo jack. Refer to the connector
packaging for wiring terminal details.
Linear controls: There are two linear controls. Potentiometer R8 sets the
sidetone monitoring level. The second control, potentiometer R6, sets the CW
speed over a range of 3 wpm (words-per-minute) to 65 wpm. This is for good
reason, these are the controls that are most frequently adjusted.
Sidetone operation: The sidetone is tone keyed by the CW keyer. This permits
you to monitor your keying and provides the aural “feedback” to assist in
sending good CW. Many transceivers already provide for internal CW sidetone
monitoring. If your transmitter does not have built-in sidetone monitoring
provisions, the VEC-221K will generate a sidetone for you. Either a monitor
speaker (4 to 32 ohms) or headphones equipped with a 3.5 mm stereo or mono