Additional Information

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Networking over internet

When, for instance, activating a special event callsign it is possible to network multiple stations over the internet.

Please be aware that a geographically distributed station is, with only a few exceptions, against the rules in contests


The most secure way to do this is to rely on a VLAN (virtual LAN) software. There are several available such as:


Each VLAN solutions have their own particular set up which is covered in their respective documentations.
With a VLAN solution, all configurations are the same as when operating in a regular LAN.

Hamachi is particularly popular since it offers a free option for up to five computers. Thanks to the communications
architecture of DXLog, this translates into five geographical locations. Since DXLog networking is based on both TCP and
UDP, it is sufficient if one operating position per location connects "as client" to the operating position assigned as
server, and the remaining stations connect using UDP.

NB. If you are using software interlock in a large multistation set up where some stations are connected over
internet it is important to configure the interlock to only consider relevant operating positions, which all
should be local. VLAN solutions typically suffer from packet loss which may result in interlock deadlocks where none
of the stations can transmit. Use the possibility to only consider named stations for the interlock in the software
interlock set up. Options->Networking->Software interlock, "Custom station ID(s)"

Port forwarding

If you are less worried about competitors or government agencies listening in on your contest data,
it is possible to route the traffic directly over the internet using port forwarding at the server.

Important security notice: This solution is not without risk. It offers no security or authentication.
Any station running the same contest configuration, knowing the URL or IP address and IP port of the
server can connect to the server station. There are no means to disconnect a station by force.

With a port forwarding solution, the following must be observed:

  • Only one of the stations should be configured as the server.
  • "Connect as client" should not be checked and "UDP network broadcast" should only be enabled if it is
used to communicate with another client on the same LAN.
  • The PC acting as server must have a fixed LAN IP address. This is done either by manually configuring the
PC to use a fixed LAN IP address, or by setting up the router in the server's LAN to to always allocate
the same IP address to it.
  • The internet connection used by the server PC must either have a fixed public IP
address or use dynamic DNS. Otherwise clients will not be able to reliable connect over the internet.
  • The server's IP port (default 9888) must be forwarded to the internet by configuring the router
connecting the server to internet. Only TCP traffic should be forwarded. UDP traffic
is broadcast and should only be used locally.

Example configuration for server for networking over internet

Example of port forwarding UI in router

  • All other PC in the multi-station set up should be set up as clients.
  • Over the internet, "Server IP" is either the public IP address of the server's internet
connection (e.g. or the dynamic DNS address (e.g. Clients connecting
over the internet does not have to enable UDP networking and should not enable a server.
  • A client may connect via UDP if it is on the same LAN as the server or a "master client".
A "master client" is a client that connects to the server using the "connect as client" option in
the networking set up panel. A "master client" can act as a UDP gateway which means that if
several computers on a LAN are part of the same multi station set up but the server is located
elsewhere, only one computer in that LAN needs to connect as a client and the rest can use UDP.

Example configuration of client for networking over internet

  • In a multi-station setting it is recommended to enable Options->Networking->Don't allow QSO logging if operator isn't logged
  • Make sure Options->Enable network is checked.

COM port keying with Microham

The Microham USB device router is a powerful software. It offers two virtual, CAT-aware, COM ports for one radio.

However, if they are not both set to the speed of the radio or closed, the ports will stop working.

DXLog currently does not allow setting the speed of port used only for keying. And virtual serial port does not have a setting for speed in Windows' device manager.

To make sure a port used for only keying is opened at the right speed do the following:

Open the interface configuration panel.

  • Select the wanted port and check the enable box.
  • Select it as Radio 1 and click Setup.
  • Select a random radio model and set the correct speed.
  • Set the wanted keying (e.g. CW = DTR, PTT = RTS, Foot switch, Active with Radio 1, etc.)
  • Press OK
  • Change from "Radio 1" to "-". Do not click Setup.
  • Press OK

SO2V audio control with Microham MK2R/MK2R+

Since the Microham MK2R/MK2R+ supports selecting/mixing of any input it is possible to create a switching
profile (a.k.a. "Function") for SO2V with's built in audio control.

Example of settings for SO2V audio control

With a profile like this, the audio control shortcuts Ctrl-Alt-A, Ctrl-Alt-T and Ctrl-Alt-S will work and
select either the main receiver in both ears, the sub receiver in both ears or, or one in each ear.

Enabling the built-in MP3 encoder in Windows

For contest recording the PC needs to have a working MP3 encoder installed. Windows does not come with such an encoder enabled.

There are several third party MP3 encoders available, such as LAME

It is also possible to enable the encoder "hidden" inside Windows.
This is described here:

Real time upload to Club Log Live Stream

DXLogStream is a basic Windows utility (which can run minimized) that uses the radio information broadcast over
UDP from and uploads logged QSO to Club Log for display using its Live Stream feature. Typical use cases
are DXPeditions, IOTA activation, Special event stations, etc.

The utility requires a valid Club Log account with the used station call sign registered.

Networking must be enabled with Options->Enable Network. UDP networking must be enabled and the station ID and
used port must be the same as set in Options->Configure network. Settings are saved by hitting ENTER or clicking
the Save button. If the UDP port is changed, the utility needs to be restarted.

The station callsign entered into the text box is the one used for upload. does not convey this as
part of the logging information via UDP which means that the corresponding setting in's contest
configuration is ignored.

The utility can be downloaded here:

Read more about Club Log Live Stream here:


Since the release of the utility above, Michael Wall, G7VJR, the founder of Club Log, has developed a much
more powerful agent for real time uploads. It works with all the three major loggers,, N1MM Logger+,
and Win-Test.

It is however less user friendly and more demanding to set up. But for a big scale DXpedition, this is the preferred agent.

You can find more information about it here:

Streamlining ESM

Starting with release 2.4.0 DXLog has a much more straightforward, consistent, and
streamlined "Enter Sends Message" or "ESM" functionality.


  • With the cursor in an empty callsign field is empty, ENTER sends RUN F1, typically CQ
  • With the cursor in a partially or correctly filled callsign field, ENTER sends the RUN INSERT message
  • With the cursor in the exchange field, ENTER sends the RUN PLUS message which (typically) concludes the QSO and logs.

When the party station has received the exchange correctly, focus is shifted to the exchange
field by pressing SPACE.

For a big gun station, where correct reception of the exchange is (almost) guaranteed, you can
automatically shift focus to the exchange field after having sent the exchange by enabling the
menu option Tools->Data entry->ESM mode change focus on $LOGGEDCALL macro.


  • With the cursor in the callsign field, ENTER sends S&P F1, typically your own callsign
  • With the cursor in an empty exchange field, ENTER sends S&P F6, which is typically a request to repeate the exchange.
  • With the cursor in a filled exchange, ENTER sends S&P INSERT, which is typically a confirmation and semi-CQ, and logs.

As of version 2.4.9 focus remains in the callsign entry field for all spot grabbing actions.
This removes the need for re-positioning the cursor after spot or callsign grabbing and also
allows for using automatic dupe checking and exchange guessing with ESM.

For a big gun station, where correct reception of the exchange is (almost) guaranteed, you can
automatically shift focus to the exchange field after having called the station by adding the $SPACE
macro to the S&P F1 message.

Diversity reception

Diversity means receiving the same signal through two different receive chains, including antenna.
With two antennas having different characteristics this can give substantial benefits in receiving
fading and/or weak signals or separating calls in a large pile-up. Particularly on low bands.

As of version 2.4.11, supports diversity operation on a selected number of radio models.
There are no GUI controls associated with diversity. automatically detects
diversity operation and enables the necessary mechanics. Diversity operation is indicated by
a small "DIV" icon in the frequency counter box for the radio's band map.

Yaesu FTDX101D

Yaesu calls this feature "Sync" and it has a dedicated button up and left of the main VFO knob.
Enabling this will make DXLog update both VFO with the same information when grabbing spots.
It will also adjust the sub VFO with the correct amount when RIT is applied to the main VFO.
Since both VFO are kept on the same frequency, split operation is not supported.

ICOM IC-7851 and IC-7610

ICOM calls this feature "Tracking" and it can be enabled either via a menu entry or a long press on the "MAIN/SUB" button.
Enabling this will make update both VFO with the same information when grabbing spots.
It will also adjust the sub VFO with the correct amount when RIT is applied to the main VFO.
Since both VFO are kept on the same frequency, split operation is not supported.

Elecraft K3/K3S

Elecraft calls this feature by its proper name. It is enabled by a long press on the "Sub" button.
It should be noted that Elecraft's implementation where the main VFO controls both the main and
sub receivers allows for split operation, i.e. transmitting on a different frequency using VFO B.

SDR integration

Contributed by Ingo SM5AJV/SE5E

Until DXLog offers SDR integration there are still ways to get a waterfall/spectrum display with DXLog.

I have integrated the free SDR software HDSDR with DXLog using Microham Device Router,
OmniRig and AutoHotkey.

As illustrated below I place the HDSDR window at the very top of the desktop with DXLog right below.

I share my transceiver's (an Elecraft K3) antenna with the SDR. The receiver antenna signal from my
K3's RX-ANT OUT is connected to the input of a 3dB power splitter. The two outputs from the splitter
are connected RX-ANT IN on the K3 and the SDR Receiver antenna input, respectively. On a K3 you
need to enable the RX-antenna input to make this to work. An additional benefit with this method
is that the SDR is protected during transmission. It is a widely used method and is e.g. described
by Bob N6TV in this presentation.

Screenshot of my desktop:


Since both DXLog and HDSDR need to communicate with the radio, you need to "split"
the CAT communication. MicroHam's USB Device Router provides a second, independent,
CAT port that can be used via HDSDR's omniRig interface.

"PORT" Tab on microHamRouter:


OmniRig settings in HDSDR:


With this set up, the radio, DxLog, and HDSDR will be fully synchronized. For instance, you can
click in the waterfall to make the radio QSY, and it is easy to quickly find a clean frequency.

To make the integration even better I use a small AutoHotkey script. The script pulls entry focus
back to DxLog after clicking on the HDSDR waterfall and in DXLog it allows you to use hotkeys to
control HDSDR. [Ctrl][Alt]+ and [Ctrl][Alt]- zooms the waterfall/spectrum
in and out, and [Ctrl][Alt]C centers it.

AutoHotkey script:

 SetTitleMatchMode, 2
 #IfWinActive, HDSDR
 F4:: return ; disable F4
 ~LButton Up::
   sleep, 1
 ^!+:: ControlSend ,, ^{+}, HDSDR
 ^!-:: ControlSend ,, ^{-}, HDSDR
 ^!c:: ControlSend ,, {c}, HDSDR

If you start two instances of HDSDR with two different SDR you can even have two waterfalls
running at the same time.

I have not yet found a way to display cluster spots in the HDSDR spectrum panel.
But I still find it very useful to check band activity and it allows me to easily find
a new Run frequency on a crowded band.