Getting the best out of the DX Cluster system

By Mike G3YPP

The most efficient way to use the DX Cluster system is to let the node that you are connected to (in our case MX0NCA-2) do the work.  In other words, set up the node so that it only sends you the spots that you want rather than have your logging software eg N1MM using valuable processing power to remove spots that you don’t want.  Don’t get them in the first place!  More importantly, this also reduces bandwidth at both ends.  

When you log on to a node for the first time, it will set up a “user account” for your Callsign and remember all of your settings.    This is important.  Any settings you make will stay in place until you change them.  

Now it may be that you want different settings for different operating periods.   Choosing which RBN spots to see, eg CW, FT8, RTTY or All, springs to mind.     You might be interested in certain bands for certain contests. You may want to limit what spots you see; for example only see spots for UK stations. Whatever your need, the use of SSIDs is a powerful tool.  


An SSID is simply a number after your Callsign eg G3YPP-1.    You can have as many as you want although managing more than a few can get tricky to remember without lots of “post-its” all over the shack.   The node sees each and every SSID as a separate Callsign creating an account for each – although the SSID is not appended to any spots you send.   Hence, you can set up different filters/commands for each SSID which are retained until you change them.     (When you are spotting someone else the SSID gets dropped). Examples could be:

Logged in as G3YPP-1           set/skimmer cw

Logged in as G3YPP-2           set/skimmer FT8

Logged in as G3YPP-3           unset/skimmer

Another factor when using SSIDs is that you can be logged into the node from more than one program/computer at the same time. The node will only allow one connection from an entity at a time. So if you log into the node with say g3ypp from N1MM you can’t be logged in as g3ypp at the same time from another program/computer. The first connection will get bumped. Using SSIDs removes this limitation.


To receive RBN spots issue the telnet command “set/skimmer”.
To stop receiving RBN spots issue the telnet command “unset/skimmer”
The set command can be mode specific such as:

set/skimmer cw
set/skimmer rtty
set/skimmer FT8

Or be more general such as:

Set/skimmer cw rtty


Using filters allow you to select which spots you want to see.   For example if you only want to see spots where the spotter is in CQ Zone 14 or 15 you can send the command:

accept/spots by_zone 14,15 or
accept/rbn by_zone 14,15

Setting filters can be as complex as you like with full Boolean logic available; the full manual is here: The DXspider User Filtering Primer


You can have up to 10 filters in operation for each callsign-ssid <0-9>

To see active filters:  show/filter


reject/spots <0-9> pattern
accept/spots <0-9> pattern

Any of the following patterns may be used in this line …

freq <range>
on <range>      
info <string>
call <prefixes>
call_dxcc <numbers>
call_itu <numbers>
call_zone <numbers>
call_state <state 2-letter abbreviations>
by <prefixes>
by_dxcc <numbers>
by_itu <numbers>
by_zone <numbers>
by_state <state 2-letter abbreviations>


show/filter – This command shows you all the spot and RBN filters that you have set up on this SSID. Very useful if you have lost the all important post-it

The show command can be useful to find specific stations or countries.  Spots for that all elusive Hawaii station can be shown with:

  • show/dx kh6 – will list all of the recent spots for KH6 over the past few days.  

show/muf <prefix> – This will show the current muf to the country selected and predict the signal strength on each band.

show/users – This shows the users currently connected to the node.

This is just a taster to show the power available at nodes and to encourage you to read further and take advantage of the system.