3 The latest release of the Mojo branch of DXSpider contains a client
4 for the Reverse Beacon Network (RBN). This is not a simple client, it
5 attempts to make some sense of the 10s of 1000s of "spots" that the
6 RBN can send PER HOUR. At busy times, actually nearly all the time, the
7 spots from the RBN come in too quickly for anybody to get anything more
8 than a fleeting impression of what's coming in.
10 Something has to try to make this manageable - which is what I have
11 tried to do with DXSpider's RBN client.
13 The RBN has a number of problems (apart from the overwhelming quantity
14 of data that it sends):
16 * Spotted callsigns, especially on CW, are not reliably
17 decoded. Estimates vary as to how bad it is but, as far as I can
18 tell, even these estimates are unreliable!
20 * The frequency given is unreliable. I have seen differences as great
23 * There is far too much (in my view) useless information in each spot
24 - even if one had time to read, decode and understand it before the
25 spot has scrolled off the top of the screen.
27 * The format of the comment is not regular. If one has both FTx and
28 "all the other" spots (CW, PSK et al) enabled at the same time,
29 one's eye is constantly having to re-adjust. Again, very difficult
30 to deal with on contest days. Especially if it mixed in with
33 So what have I done about this? Look at the sample of input traffic
36 05Jul2020@22:59:31 (chan) <- I SK0MMR DX de KM3T-2-#: 14100.0 CS3B CW 24 dB 22 WPM NCDXF B 2259Z
37 05Jul2020@22:59:31 (chan) <- I SK0MMR DX de KM3T-2-#: 28263.9 AB8Z/B CW 15 dB 18 WPM BEACON 2259Z
38 05Jul2020@22:59:31 (chan) <- I SK0MMR DX de LZ3CB-#: 7018.20 RW1M CW 10 dB 18 WPM CQ 2259Z
39 05Jul2020@22:59:31 (chan) <- I SK0MMR DX de W9XG-#: 14057.6 K7GT CW 7 dB 21 WPM CQ 2259Z
40 05Jul2020@22:59:31 (chan) <- I SK0MMR DX de G0LUJ-#: 14100.1 CS3B CW 18 dB 20 WPM NCDXF B 2259Z
41 05Jul2020@22:59:32 (chan) <- I SK0MMR DX de LZ4UX-#: 7018.3 RW1M CW 13 dB 18 WPM CQ 2259Z
42 05Jul2020@22:59:32 (chan) <- I SK0MMR DX de LZ4AE-#: 7018.3 RW1M CW 28 dB 18 WPM CQ 2259Z
43 05Jul2020@22:59:32 (chan) <- I SK0MMR DX de W1NT-6-#: 28222.9 N1NSP/B CW 5 dB 15 WPM BEACON 2259Z
44 05Jul2020@22:59:32 (chan) <- I SK0MMR DX de W1NT-6-#: 28297.0 NS9RC CW 4 dB 13 WPM BEACON 2259Z
45 05Jul2020@22:59:32 (chan) <- I SK0MMR DX de F8DGY-#: 7018.2 RW1M CW 23 dB 18 WPM CQ 2259Z
46 05Jul2020@22:59:33 (chan) <- I SK0MMR DX de 9A1CIG-#: 7018.30 RW1M CW 20 dB 18 WPM CQ 2259Z
47 05Jul2020@22:59:33 (chan) <- I SK0MMR DX de LZ7AA-#: 7018.3 RW1M CW 16 dB 18 WPM CQ 2259Z
48 05Jul2020@22:59:33 (chan) <- I SK0MMR DX de DK9IP-#: 7018.2 RW1M CW 21 dB 18 WPM CQ 2259Z
49 05Jul2020@22:59:33 (chan) <- I SK0MMR DX de WE9V-#: 10118.0 N5JCB CW 15 dB 10 WPM CQ 2259Z
50 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de DJ9IE-#: 7028.0 PT7KM CW 15 dB 10 WPM CQ 2259Z
51 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de DJ9IE-#: 7018.3 RW1M CW 31 dB 18 WPM CQ 2259Z
52 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de DD5XX-#: 7018.3 RW1M CW 21 dB 18 WPM CQ 2259Z
53 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de DE1LON-#: 14025.5 EI5JF CW 13 dB 19 WPM CQ 2259Z
54 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de DE1LON-#: 7018.3 RW1M CW 24 dB 18 WPM CQ 2259Z
55 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de ON6ZQ-#: 7018.3 RW1M CW 22 dB 18 WPM CQ 2259Z
56 05Jul2020@22:59:34 (chan) <- I SK0MMR DX de OH6BG-#: 3516.9 RA1AFT CW 15 dB 25 WPM CQ 2259Z
57 05Jul2020@22:59:35 (chan) <- I SK0MMR DX de HA1VHF-#: 7018.3 RW1M CW 30 dB 18 WPM CQ 2259Z
58 05Jul2020@22:59:35 (chan) <- I SK0MMR DX de F6IIT-#: 7018.4 RW1M CW 32 dB 18 WPM CQ 2259Z
59 05Jul2020@22:59:36 (chan) <- I SK0MMR DX de HB9BXE-#: 7018.3 RW1M CW 23 dB 18 WPM CQ 2259Z
60 05Jul2020@22:59:37 (chan) <- I SK0MMR DX de SM0IHR-#: 7018.3 RW1M CW 21 dB 18 WPM CQ 2259Z
61 05Jul2020@22:59:37 (chan) <- I SK0MMR DX de DK0TE-#: 7018.3 RW1M CW 26 dB 18 WPM CQ 2259Z
62 05Jul2020@22:59:37 (chan) <- I SK0MMR DX de OE9GHV-#: 7018.3 RW1M CW 40 dB 19 WPM CQ 2259Z
63 05Jul2020@22:59:37 (chan) <- I SK0MMR DX de CX6VM-#: 10118.0 N5JCB CW 20 dB 10 WPM CQ 2259Z
64 05Jul2020@22:59:37 (chan) -> D G1TST DX de F8DGY-#: 7018.3 RW1M CW 23dB Q:9* Z:20 16 2259Z 14
65 05Jul2020@22:59:38 (chan) <- I SK0MMR DX de HB9JCB-#: 7018.3 RW1M CW 16 dB 18 WPM CQ 2259Z
66 05Jul2020@22:59:39 (chan) <- I SK0MMR DX de HB9JCB-#: 3516.9 RA1AFT CW 9 dB 26 WPM CQ 2259Z
67 05Jul2020@22:59:39 (chan) <- I SK0MMR DX de KO7SS-7-#: 14057.6 K7GT CW 6 dB 21 WPM CQ 2259Z
68 05Jul2020@22:59:39 (chan) <- I SK0MMR DX de K9LC-#: 28169.9 VA3XCD/B CW 9 dB 10 WPM BEACON 2259Z
69 05Jul2020@22:59:40 (chan) <- I SK0MMR DX de HB9DCO-#: 7018.2 RW1M CW 25 dB 18 WPM CQ 2259Z
70 05Jul2020@22:59:40 (chan) <- I SK0MMR DX de EA5WU-#: 7018.3 RW1M CW 19 dB 18 WPM CQ 2259Z
72 * As you can see, there are frequently more than one spotter for a
75 * I normalise the frequency and cache up to 9 copies from different
76 spots. In order to do this I have to wait a few (configurable) seconds
77 for the client to collect a reasonable number of copies. More copies
78 may come in after 9 copies have been received. Once I have enough
79 copies to be sure that the callsign is at least agreeed upon by more
80 than one skimmer, or the wait timer goes off, I emit a spot. By this
81 means I can reduce the number of spots sent to a node user by up to a
82 factor of 10 for CW etc spots and about 8 for FTx spots.
84 For example, from the trace above, all the RW1M RBN spots become just
87 DX de F8DGY-#: 7018.3 RW1M CW 23dB Q:9* Z:20 16 2259Z 14
89 * No RBN spots can leak out of the node to the general cluster. Each
90 node that wants to use the RBN *must* establish their own
91 connections to the RBN.
93 * Currently no RBN spots are stored. This may well change but how and
94 where these spots are stored is not yet decided. Only "DXSpider
95 curated" spots (like the example above) will be stored (if/when they
96 are). Sh/dx will be suitably modified if storage happens.
98 * There are some things that need to be explained:
100 a) The input format from the RBN is not the same as format emitted by
101 the cluster node. This is part of the unhelpfulness to mixing a raw
102 RBN feed with normal spots.
104 b) Each spot sent out to a node user has a "Qwalitee" marker, In this
105 case Q:9*. The '9' means that I have received 9 copies of this spot
106 from different skimmers and, in this case, they did not agree on the
107 frequency (7018.2 - 7018.4) which is indicated by a '*'. The frequency
108 shown is the majority decision. If this station has been active for
109 some time and he is still calling CQ after some time (configurable,
110 but currently 60 minutes) and gaps for QSOs or tea breaks are ignored,
111 then a '+' character will be added.
113 If the "Qualitee" Q:1 is seen on a CW spot, then only one skimmer has
114 seen that spot and the callsign *could* be wrong, but frequently, if
115 it is wrong, it is more obvious than the example below. But if Q is
116 Q:2 and above, then the callsign is much more likely to be correct.
118 DX de DJ9IE-#: 14034.9 UN7BBD CW 4dB Q:5*+ 17 1444Z 14
119 DX de OL7M-#: 14037.9 UA6LQ CW 13dB Q:7 16 1448Z 15
120 DX de LZ3CB-#: 28050.2 DL4HRM CW 7dB Q:1 14 1448Z 20
122 c) I ditch the WPM and the 'CQ' as not being hugely relevant.
124 d) If there is a Z:nn[,mm...], then this spot was also heard by
125 skimmers in other zones. In this example, it means that this call was
126 also heard in CQ Zone 20. This list does NOT include the cq zone of
127 the skimmer nor the spot. If you would like to see these then do
128 'set/dxcq'. This setting is active for all the examples in this
129 document. This is completely optional.
131 There can be a ',' separated list of as many zones where this spot was
132 also heard by another skimmers, up to the space available in the
135 DX de LZ4UX-#: 14015.5 ON7TQ CW 6dB Q:9 Z:5,14,15,40 14 0646Z 20
136 DX de VE7CC-#: 3573.0 N8ADO FT8 -14dB Q:4 Z:4,5 4 0647Z 3
137 DX de DM7EE-#: 14027.5 R1AC CW 9dB Q:9* Z:5,15,17,20 16 0643Z 14
138 DX de WE9V-#: 7074.0 EA7ALL FT8 -9dB Q:2+ Z:5 14 0641Z 4
140 e) I shorten the skimmer callsign to 6 characters - having first
141 chopped off any SSIDs, spurious /xxx strings from the end, leaving
142 just the base callsign, before (re-)adding '-#' on the end. This is
143 done to minimise the misalignment of the spot rightwards, as in the
144 incoming skimmer spot from KO7SS-7-# below. There are some very
145 strange skimmer callsigns with all sorts of spurious endings, all of
146 which I attempt to reduce to the base callsign. Some skimmer base
147 callsigns still might be shortened for display purposes. Things like
148 '3V/K5WEM' won't fit in six characters but the whole base callsign is
149 used for zone info, internally, but only the first 6 characters are
150 displayed in any spot.
152 05Jul2020@22:59:39 (chan) <- I SK0MMR DX de HB9JCB-#: 3516.9 RA1AFT CW 9 dB 26 WPM CQ 2259Z
153 05Jul2020@22:59:39 (chan) <- I SK0MMR DX de KO7SS-7-#: 14057.6 K7GT CW 6 dB 21 WPM CQ 2259Z
154 05Jul2020@22:59:39 (chan) <- I SK0MMR DX de K9LC-#: 28169.9 VA3XCD/B CW 9 dB 10 WPM BEACON 2259Z
156 f) I have a filter set (accept/spot by_zone 14 and not zone 14 or zone
157 14 and not by_zone 14) which will give me the first spot that either
158 spot or skimmer is in zone 14 but the other isn't. For those of us
159 that are bad at zones (like me) sh/dxcq is your friend. You can have
160 separate filters just for RBN spots if you want something different to
161 your spot filters. Use acc/rbn or rej/rbn. NB: these will completely
162 override your spot filters for RBN spots. Obviously "real" spots will
163 will continue to use the spot filter(s).
165 g) If there is NO filter in operation, then the skimmer spot with the
166 LOWEST signal strength will be shown. This implies that if any extra
167 zones are shown, then the signal will be higher.
169 h) A filter can further drastically reduce the output sent to the
170 user. As this STATS line shows:
172 23:22:45 (*) RBN:STATS hour SK0MMR raw: 5826 sent: 555 delivered: 70 users: 1
174 For this hour, I received 5826 raw spots from the CW etc RBN, which
175 produced 555 possible spots, which my filter reduced to 70 that were
176 actually delivered to G1TST. For the FTx RBN, I don't have a filter
177 active and so I got all the possibles:
179 23:22:45 (*) RBN:STATS hour SK1MMR raw: 13354 sent: 1745 delivered: 1745 users: 1
181 ---------------------------------------------------------------------
183 So how do you go about using this:
185 First you need to create an RBN user. Now you can use any call you
186 like and it won't be visible outside of the node. I call mine SK0MMR
187 and SK1MMR. One of these connects to the "standard" RBN port that
188 outputs CW, BEACON, DXF, PSK and RTTY spots, and the other connects to
189 the RBN port that just outputs FT4 and FT8 spots.
191 set/rbn sk0mmr sk1mmr
193 Now create connect scripts in /spider/connect/sk0mmr (and similarly
194 sk1mmr). They look like this:
196 /spider/connect/sk0mmr:
198 connect telnet telnet.reversebeacon.net 7000
199 'call:' '<node callsign here'
201 /spider/connect/sk1mmr:
203 connect telnet telnet.reversebeacon.net 7001
204 'call:' '<node callsign here'
206 Now put them in your local crontab in /spider/local_cmd/crontab:
208 * * * * * start_connect('sk0mmr') unless connected('sk0mmr')
209 * * * * * start_connect('sk1mmr') unless connected('sk1mmr')
211 This will check once every minute to see if each RBN connection is
212 active, you can check what is connected with the 'links' command:
214 Ave Obs Ping Next Filters
215 Callsign Type Started Uptime RTT Count Int. Ping Iso? In Out PC92? Address
216 GB7DJK DXSP 5-Jul-2020 1722Z 7h 6m 8s 0.02 2 300 89 Y 163.172.11.79
217 SK0MMR RBN 5-Jul-2020 1722Z 7h 6m 8s 0 0 198.137.202.75
218 SK1MMR RBN 5-Jul-2020 1722Z 7h 6m 8s 0 0 198.137.202.75
220 The connections are sometimes dropped or become stuck, I have a
221 mechanism to detect this and it will disconnect that RBN connection
222 and the reconnection will be reconnected by the crontab, just like any
225 I use the crontab, rather than restarting immediately after
226 disconnection, to prevent race conditions (or just slow them down to
227 one disconnection a minute).
229 The first time a connection is made, after node startup, there is a 5
230 minute pause before RBN spots come out for users. This is done to fill
231 up (or "train") the cache. Otherwise the users will be overwhelmed by
232 spots - it slows down reasonably quickly - but experiment shows that 5
233 minutes is a reasonable compromise. The delay is configurable,
234 globally, for all RBN connections, but in future is likely to be
235 configurable per connection. Basically, because the FTx RBN data is
236 much more bursty and there is more of it (except on CW contests), it
237 could do with a somewhat longer training period than the CW etc RBN
240 If a connection drops and reconnects. There is no delay or extra
243 For users. At the moment. There is a single command that sets or
244 unsets ALL RBN spot sorts:
249 Very soon this will be replaced with a '(un)set/skimmer' command that
250 allow the user to choose which categories they want. Filtering can be
251 used in conjunction with this proposed command to further refine
254 This still very much "work in progress" and will be subject to
255 change. But I am grateful to the feedback I have received, so far,
263 But if you have comments, suggestions and brickbats please email me or