K1EL
WKUSB with WinKeyer3 User Manual
WKUSB
WKUSB User Manual
12/20/2017 Rev 1.0
Page 9
Connecting WKUSB-SMT to your station
Minimally all you need to do is connect the USB cable from WKUSB
to a USB port on your PC
and connect the key output to the keying input on your rig. Since WKUSB performs the keying
function it drives your rig in the same manner as a straight key. In other words there are only two
leads, ground and key control. For that reason a keying cable is quite easy to build.
Hamcrafters sells a WKUSB universal keying cable kit that covers 95% of keying requirements.
Keying cable details
An RCA plug is required at one end and the other end will have a connector that will mate to your
rig’s key input. Usually this is a ¼ inch phone plug, we recommend using a stereo plug. A two
wire cable is all that is required to key a typical transceiver. Plug the RCA side into either KEY1 or
KEY2 and the other side directly into your transceiver’s key input jack. On the transceiver end,
the key line goes to tip and ground goes to the sleeve.
GROUND
No Connect
KEYLINE
sleeve
tip
ring
Transceiver/Transmitter end of cable
Make sure you disable the radio’s internal keyer, if it has one, and set it up for straight key
operation. It’s always a good idea to test your keying cable before using it with WK. Plug the
cable into your transceiver and leave the keyer end unconnected. Now set up your transceiver for
transmit and then short the keyer cable end, tip to sleeve, with a clip lead. If this doesn’t work
then either the cable is not made correctly or the radio is not in break in mode. If you get dits or
dahs, then the keyer in the radio is still enabled. Some transceivers want you to use a stereo plug
even if the internal keyer is disabled, it’s a good idea to use a stereo connector at the radio end
no matter what and leave the ring unconnected.
If you want to key a transmitter with vacuum tube finals, WKUSB will work fine because it has a
solid state keying relay rated for +\-350V switching at 120ma. This covers grid block keying but it
probably will NOT be suitable for cathode keying. In any case always check the transmitter’s
manual for keying requirements before plugging WKUSB in.
WKUSB’s RCA connectors are electrically isolated from WKUSB’s enclosure and ground. This
means that you can directly connect your transceiver to WKUSB with PC attached and not worry
about ground loops or RF getting into your PC through WKUSB.
PTT Connection
PTT will not be used in most radio setups. It is provided to run an external antenna switch or to
pre-key a linear amplifier. If you are just driving a barefoot transceiver, PTT will not be required.
If you do need PTT, then WKUSB provides useful functionality. PTT is asserted before KEY and
is held for the entire transmit interval. Both lead-in and tail delays are adjustable. The PTT
connections are wired the same as the KEY, make sure that PTT is enabled in your configuration.