K1EL K45 CW Keyboard and Reader Manual K45B
K45 User’s Manual – Rev B.0
3/8/2023
Page 33
If you want to see the expanded message, press the Windows key, and watch it in the Fast Tx View window
as it is sent.
You can adjust the sending speed at any time by turning the rotary encoder or pressing the up/down arrow
keys. The new transmit speed will be displayed on the right side of the status line.
A handy command is Tune; press
^T (CTL-T)
and the K45 will hold key and sidetone on until you press
either a key on the keyboard or press the CW paddle. A 50% tune duty cycle can be selected by an entry in
the Configuration Menu #2:
Tune 50%
.
One last thing to mention before we move on is how to use a set of paddles with the K45. You can enter
Morse on the paddles at any time. If the K45 is sending a message or something from the outgoing queue, it
will be cancelled by the first paddle press and you can break right in. If you want to exchange the dit and dah
paddles, there is a setting in Configuration Menu #2 for that as well as other Paddle settings.
Audio Input for CWR Checkout
The K45 has a built in Morse Reader (CWR) that demodulates, decodes, and displays Morse from audio
input that is connected to the K45’s audio input. There are several guidelines for audio input that if followed
will optimize the performance of the reader. The AF input is both low level and high impedance. It is
intended to be driven by the audio line out from a radio receiver. It takes a little bit of work to accomplish
this, but it is well worth the effort. Unlike a speaker output (which is both low impedance and high level) the
line output provides a fixed audio level that is not affected by the radio’s AF gain setting.
A radio’s speaker output is not suitable for driving the K45 since in most cases when you plug a connector
into the radio’s speaker jack, the radio’s internal speaker is disabled. The K45 does not have an internal
speaker so there will be no audio to listen to. An option is to use a splitter cable and feed one side to a
speaker and the other side to the K45. This will work to some degree but since the level is dependent on the
AF gain control, you may have to adjust the CWR gain every time you change the radio’s AF gain. So
bottom line, use line out if possible.
SignaLink
TM
or similar devices that plug into a radio’s AUX connector can provide an easy way to get at the
line out audio signal. Most of these devices bring line out to a separate 1/8” AUX jack that can easily be
connected to the K45.
CWR Basics
It’s easy to operate the CWR but there are just a few things to keep in mind. First, make sure you are
looking at the receive window. The filters in the K45 CWR are fixed at 725 Hz. For best results, adjust your
receiver so that its passband is centered on 725 Hz. When you hear a station, slowly tune through it while
watching the five bar LCD display on the status line. Watch for a peak movement to the right. You will see a
peak as you pass through 725 Hz. It is easier to adjust the receiver passband at this time. Once you have
the station tuned in properly, CW will be decoded and displayed. When audio overload happens, the right
most bar will display a +. For best results adjust the audio level to avoid overload. The K45 has adjustable
gain control so that you can adjust the audio level without changing your receiver’s audio level. (see CWR
Adjustments on page 34)
CWR Tuning Display
+
High Signal
Level
Low Signal
Level
Figure 33 – CW Level Indicator
The LCD bar display is a very simple indication of both tuning frequency and signal strength. For this
reason, a signal that rapidly changes in signal strength can make tuning slightly more difficult. The accuracy
of CW decoding can vary as a signal fades in and out. With very deep fades, the K45 CWR may print an
erroneous character or get out of sync for a couple of characters. With some practice it is fairly easy to learn
what the K45 is looking for and adjust the receiver tuning appropriately.