- Now set a password for the user ...
-
-
-
- # passwd sysop
- # New UNIX password:
- # Retype new UNIX password:
- passwd: all authentication tokens updated successfully
-
-
-
-
-
- 1\b1.\b.3\b3.\b. I\bIn\bns\bst\bta\bal\bll\bli\bin\bng\bg t\bth\bhe\be s\bso\bof\bft\btw\bwa\bar\bre\be
-
- Now to unpack the DX Spider distribution, set symbolic links and group
- permissions. Copy the tarball to /home/sysop and do the following.
-
-
-
- # cd ~sysop
- # tar xvfz spider-1.46.tar.gz
- # ln -s ~sysop/spider /spider
- # groupadd -g 251 spider (or another number)
-
-
-
-
- If you do not have the command _\bg_\br_\bo_\bu_\bp_\ba_\bd_\bd available to you simply add a
- line in /etc/group by hand.
-
-
-
- # vi /etc/group (or your favorite editor)
-
- You also need to add some others to the group, including your own
- callsign (this will be used as an alias) and root. The finished line
- in /etc/group should look something like this
-
- spider:x:251:sysop,g0vgs,root
-
-
- The next step is to set the permissions on the Spider directory tree
- and files ....
-
-
-
- # chown -R sysop.spider spider
- # find . -type d -exec chmod 2775 {} \;
- # find . -type f -exec chmod 775 {} \;
-
-
-
-
-
- This last step allows various users of the group _\bs_\bp_\bi_\bd_\be_\br to have write
- access to all the directories. This is not really needed just yet but
- will be useful when web interfaces start to appear.
-
-
- Finally, you need to fix the permissions on the ax25_call and
- netrom_call programs. Check where they are with the _\bl_\bo_\bc_\ba_\bt_\be command
- and alter the permissions with the _\bc_\bh_\bm_\bo_\bd command like this ..
-
-
-
- # chown root ax25_call netrom_call
- # chmod 4775 ax25_call netrom_call
-
-
-
-
-
- 1\b1.\b.4\b4.\b. S\bSe\bet\btt\bti\bin\bng\bg c\bca\bal\bll\bls\bsi\big\bgn\bns\bs e\bet\btc\bc
-
- Now login to your machine as the user you created earlier. In my case
- that user is called _\bs_\by_\bs_\bo_\bp. Once logged in, issue the following
- commands ....
-
-
-
- $ cd /spider
- $ mkdir local
- $ mkdir local_cmd
- $ cp perl/DXVars.pm.issue local/DXVars.pm
- $ cd local
- $ vi DXVars.pm (or your favourite editor)
-
-
-
-
-
- Using the distributed DXVars.pm as a a template, set your cluster
- callsign, sysop callsign and other user info to suit your own
- environment. Note that this a perl file which will be parsed and
- executed as part of the cluster. If you get it wrong then perl will
- complain when you start the cluster process. It is important only to
- alter the text of any section. Some of the lines look a little odd.
- Take this line for example ....
-
-
- $myemail = "ianmaude\@btinternet.com";
-
-
- There appears to be an extra slash in there. However this has to be
- there for the file to work so leave it in.
-
-
- P\bPL\bLE\bEA\bAS\bSE\bE U\bUS\bSE\bE C\bCA\bAP\bPI\bIT\bTA\bAL\bL L\bLE\bET\bTT\bTE\bER\bRS\bS F\bFO\bOR\bR C\bCA\bAL\bLL\bLS\bSI\bIG\bGN\bNS\bS
-
-
- DON'T alter the DXVars.pm (or any other file) in /spider/perl, they
- are overwritten with every release. Any files or commands you place in
- /spider/local or /spider/local_cmd will automagically be used in
- preference to the ones in /spider/perl EVEN while the cluster is
- running!
-
-
- Save the new file and change directory to ../perl ....
-
-
-
- $ cd ../perl
-
-
-
-
-
- Now type the following command which creates the basic user file with
- you as the sysop.
-
-
-
- $ create_sysop.pl
-
-
-
-
-
- 1\b1.\b.5\b5.\b. S\bSt\bta\bar\brt\bti\bin\bng\bg u\bup\bp f\bfo\bor\br t\bth\bhe\be f\bfi\bir\brs\bst\bt t\bti\bim\bme\be
-
- We can now bring spider up for the first time and see if all is well
- or not! It should look something like this ...
-
-
-
- $ cluster.pl
- DXSpider DX Cluster Version 1.46
- Copyright (c) 1998 Dirk Koopman G1TLH
- loading prefixes ...
- loading band data ...
- loading user file system ...
- starting listener ...
- reading existing message headers
- reading cron jobs
- orft we jolly well go ...
-
-
-
-
-
- If all is well then login on another term or console as _\bs_\by_\bs_\bo_\bp and cd
- to /spider/perl. Now issue the following command ...
-
-
-
-
- $ client.pl
-
-
-
-
-
- This should log you into the cluster as the sysop under the alias
- callsign we set earlier. In this case the callsign is G0VGS. The
- cluster callsign is set in the DXVars.pm file in /spider/local. In
- this case we will assume that this was set as GB7MBC. You should
- therefore see this when you login ....
-
-
-
- G0VGS de GB7MBC 19-Nov-1999 2150Z >
-
-
-
-
- If you do, congratulations! If not, look over the instructions again,
- you have probably missed something out. You can shut spider down
- again with the command ....
-
-
-
- shutdown
-
-
-
-
-
- and both the cluster and the client should return to Linux prompts.
-
-
- 2\b2.\b. T\bTh\bhe\be C\bCl\bli\bie\ben\bnt\bt p\bpr\bro\bog\bgr\bra\bam\bm
-
- In earlier versions of Spider, all the processes were Perl scripts.
- This was fine but with a lot of users your computer memory would soon
- be used up. To combat this a new client was written in "C". This
- client only works for _\bi_\bn_\bc_\bo_\bm_\bi_\bn_\bg connects at the moment. Before you can
- use it though it has to be "made". CD to /spider/src and type _\bm_\ba_\bk_\be.
- You should see the output on your screen and hopefully now have a
- small C program called _\bc_\bl_\bi_\be_\bn_\bt. Leave it in this directory.
-
-
- 3\b3.\b. C\bCo\bon\bnf\bfi\big\bgu\bur\bra\bat\bti\bio\bon\bn
-
- 3\b3.\b.1\b1.\b. A\bAl\bll\blo\bow\bwi\bin\bng\bg a\bax\bx2\b25\b5 c\bco\bon\bnn\bne\bec\bct\bts\bs f\bfr\bro\bom\bm u\bus\bse\ber\brs\bs
-
- As stated previously, the aim of this document is not to tell you how
- to configure Linux or the ax25 utilities. However, you do need to add
- a line in your ax25d.conf to allow connections to DXSpider for your
- users. For each interface that you wish to allow connections on, use
- the following format ...
-
-
-
- default * * * * * * - sysop /spider/src/client client %u ax25
-
-
-
-
- or, if you wish your users to be able to use SSID's on their callsigns
- ..
-
-
- default * * * * * * - sysop /spider/src/client client %s ax25
-
-
-
-
-
- 3\b3.\b.2\b2.\b. A\bAl\bll\blo\bow\bwi\bin\bng\bg t\bte\bel\bln\bne\bet\bt c\bco\bon\bnn\bne\bec\bct\bts\bs f\bfr\bro\bom\bm u\bus\bse\ber\brs\bs
-
- Allowing telnet connections is quite simple. Firstly you need to add
- a line in /etc/services to allow connections to a port number, like
- this ....
-
-
-
- spdlogin 8000/tcp # spider anonymous login port
-
-
-
-
- Then add a line in /etc/inetd.conf like this ....
-
-
-
- spdlogin stream tcp nowait root /usr/sbin/tcpd /spider/src/client login telnet
-
-
-
-
-
- This needs to be added above the standard services such as ftp, telnet
- etc. Once this is done, you need to restart inetd like this ....
-
-
-
- killall -HUP inetd
-
-
-
-
-
-
- Now login as _\bs_\by_\bs_\bo_\bp and cd spider/perl. You can test that spider is
- accepting telnet logins by issuing the following command ....
-
-
-
- client.pl login telnet
-
-
-
-
- You should get a login prompt and on issuing a callsign, you will be
- given access to the cluster. Note, you will not get a password login.
- There seems no good reason for a password prompt to be given so it is
- not asked for.
-
-
- Assuming all is well, then try a telnet from your linux console ....
-
-
-
- telnet localhost 8000
-
-
-
-
- You should now get the login prompt and be able to login as before.
-
-
- 3\b3.\b.3\b3.\b. S\bSe\bet\btt\bti\bin\bng\bg u\bup\bp n\bno\bod\bde\be c\bco\bon\bnn\bne\bec\bct\bts\bs
-
- In order to allow cluster node connections, spider needs to know that
- the connecting callsign is a cluster node. This is the case whether
- the connect is incoming or outgoing. In spider this is a simple task
- and can be done in runtime.
-
-
- Later versions of Spider can distinguish different software and treat
- them differently. For example, the WCY beacon cannot be handles by
- AK1A type nodes as AK1A does not know what to do with PC73. There are
- 4 different types of node at present and although they may not have
- any major differences at the moment, it allows for compatibility. The
- 4 types are ...
-
-
-
- set/node (AK1A type)
- set/spider
- set/dxnet
- set/clx
-
-
-
-
-
- For now, we will assume that the cluster we are going to connect to is
- an AK1A type node.
-
-
- Start up the cluster as you did before and login as the sysop with
- client.pl. The cluster node I am wanting to make a connection to is
- GB7BAA but you would obviously use whatever callsign you required. At
- the prompt type ...
-
-
-
- set/node gb7baa
-
-
-
-
-
- The case does not matter as long as you have a version of DXSpider
- later than 1.33. Earlier versions required the callsign to be in
- upper case.
-
-
- That is now set, it is as simple as that. To prove it, login on yet
- another console as sysop and issue the command ...
-
-
-
- client.pl gb7baa (using the callsign you set as a node)
-
-
-
-
-
- You should get an initialisation string from DXSpider like this ...
-
-
-
- client.pl gb7baa
- PC38^GB7MBC^~
-
-
-
-
- If the callsign you just set up as a cluster node is for an incoming
- connect, this is all that needs to be done. If the connection is to
- be outgoing then a connection script needs to be written.
-
-
- 3\b3.\b.4\b4.\b. C\bCo\bon\bnn\bne\bec\bct\bti\bio\bon\bn s\bsc\bcr\bri\bip\bpt\bts\bs
-
- Because DXSpider operates under Linux, connections can be made using
- just about any protocol; AX25, NETRom, tcp/ip, ROSE etc are all
- possible examples. Connect scripts live in the /spider/connect
- directory and are simple ascii files. Writing a script for
- connections is therefore relatively simple.
-
-
- The connect scripts consist of lines which start with the following
- keywords or symbols:-
-
-
-
- # All lines starting with a # are ignored, as are completely
- blank lines.
-
- timeout timeout followed by a number is the number of seconds to wait for a
- command to complete. If there is no timeout specified in the script
- then the default is 60 seconds.
-
- abort abort is a regular expression containing one or more strings to look
- for to abort a connection. This is a perl regular expression and is
- executed ignoring case.
-
- connect connect followed by ax25 or telnet and some type dependent
- information. In the case of a telnet connection, there can be up to
- two parameters.
- The first is the ip address or hostname of the computer you wish to
- connect to and the second is the port number you want to use (this
- can be left out if it is a normal telnet session).
- In the case of an ax25 session then this would normally be a call to
- ax25_call or netrom_call as in the example above. It is your
- responsibility to get your node and other ax25 parameters to work
- before going down this route!
-
- ' line in a chat type script. The words/phrases normally come in pairs,
- either can be empty. Each line reads input from the connection until
- it sees the string (or perl regular expression) contained in the
- left hand string. If the left hand string is empty then it doesn't
- read or wait for anything. The comparison is done ignoring case.
- When the left hand string has found what it is looking for (if it is)
- then the right hand string is sent to the connection.
- This process is repeated for every line of chat script.
-
- client client starts the connection, put the arguments you would want here
- if you were starting the client program manually. You only need this
- if the script has a different name to the callsign you are trying to
- connect to (i.e. you have a script called other which actually
- connects to GB7DJK-1 [instead of a script called gb7djk-1]).
-
-
-
-
-
- There are many possible ways to configure the script but here are two
- examples, one for a NETRom/AX25 connect and one for tcp/ip.
-
-
-
- timeout 60
- abort (Busy|Sorry|Fail)
- # don't forget to chmod 4775 netrom_call!
- connect ax25 /usr/sbin/netrom_call bbs gb7djk g1tlh
- # you can leave this out if you call the script 'gb7dxm'
- client gb7dxm ax25
-
-
-
-
-
-
-
-
- timeout 15
- connect telnet dirkl.tobit.co.uk
- # tell GB7DJK-1 that it is connected to GB7DJK
- # you can leave this out if you call this script 'gb7djk'
- client gb7djk telnet
-
-
-
-
-
- Both these examples assume that everything is set up properly at the
- other end. You will find other examples in the /spider/examples
- directory.
-
-
- 3\b3.\b.5\b5.\b. S\bSt\bta\bar\brt\bti\bin\bng\bg t\bth\bhe\be c\bco\bon\bnn\bne\bec\bct\bti\bio\bon\bn
-
- You start the connection, from within a sysop enabled cluster login,
- by typing in the word _\bc_\bo_\bn_\bn_\be_\bc_\bt followed by a script name like this ....
-
-
-
- G0VGS de GB7MBC 13-Dec-1998 2041Z >connect gb7djk-1
- connection to GB7DJK-1 started
- G0VGS de GB7MBC 13-Dec-1998 2043Z >
-
-
-
-
- This will start a connection using the script called _\bg_\bb_\b7_\bd_\bj_\bk_\b-_\b1. You
- can follow the connection by watching the term or console from where
- you started _\bc_\bl_\bu_\bs_\bt_\be_\br_\b._\bp_\bl. You should see something like this ...
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
- <- D G1TLH connect gb7djk-1
- -> D G1TLH connection to GB7DJK-1 started
- -> D G1TLH G1TLH de GB7DJK 13-Dec-1998 2046Z >
- timeout set to 15
- CONNECT sort: telnet command: dirkl.tobit.co.uk
- CHAT "login" -> "gb7djk"
- received "
- Red Hat Linux release 5.1 (Manhattan)
- Kernel 2.0.35 on an i586
- "
- received "login: "
- sent "gb7djk"
- CHAT "word" -> "gb7djk"
- received "gb7djk"
- received "Password: "
- sent "gb7djk"
- Connected to GB7DJK-1, starting normal protocol
- <- O GB7DJK-1 telnet
- -> B GB7DJK-1 0
- GB7DJK-1 channel func state 0 -> init
- <- D GB7DJK-1
- <- D GB7DJK-1 Last login: Sun Dec 13 17:59:56 from dirk1
- <- D GB7DJK-1 PC38^GB7DJK-1^~
- <- D GB7DJK-1 PC18^ 1 nodes, 0 local / 1 total users Max users 0 Uptime
- 0 00:00^5447^~
- etc
-
-
-
-
-
- With later versions of Spider there is a set/login command for users.
- This tells them when a user or node logs in or out. If you do not add
- a line to your scripts after the final line (or before the client line
- which should always be last if needed) then the login/logout
- information will be sent to users _\bb_\be_\bf_\bo_\br_\be the login actually completes.
- This means if a node is unreachable, it will continue sending logins
- and logouts to users even though it is not actually connecting. To
- avoid this use the following line ...
-
-
-
-
-
-
-
-
- In a script, this might look like ...
-
-
-
- timeout 35
- abort (Busy|Sorry|Fail)
- connect telnet mary 3000
-
-
-
-
-
- 3\b3.\b.6\b6.\b. T\bTe\bel\bln\bne\bet\bt e\bec\bch\bho\bo
-
- Cluster links in particular suffer greatly from the presence of telnet
- echo. This is caused by the telnet negotiation itself and can create
- at worst severe loops. At best it creates unnecessary bandwidth and
- large logfiles! There are things that can be done to limit this
- problem but will not always work dependent on the route taken to
- connect.
-
-
- Telnet echo itself should only be a problem if the connection is being
- made to the telnet port (23). This port uses special rules that
- include echo negotiation. If the connection is to a different port,
- such as 8000, this negotiation does not happen and therefore no echo
- should be present.
-
-
- Sometimes it is not possible to make a direct connection to another
- node and this can cause problems. There is a way of trying to
- suppress the telnet echo but this will not always work, unfortunately
- it is difficult to be more specific. Here is an example of what I
- mean ...
-
-
-
- timeout 35
- abort (Busy|Sorry|Fail)
- connect telnet mary.lancs.ac.uk
-
-
-
-
- So, the first connection is made by Spider. This is fine as Spider
- uses the Net_Telnet script from within perl. This actually uses TCP
- rather than TELNET so no negotiation will be done on the first
- connection. Once connected to mary.lancs.ac.uk, the command is sent
- to suppress echo. Now a telnet is made to a cluster node that is
- accepting connections on port 23. The problem with this link is that
- the negotiation is made by the remote machine, therefore you have no
- control over it. The chances are that this link will create echo and
- there will be no way you can stop it.
-
-
-
- 4\b4.\b. A\bAu\but\bto\bom\bma\bat\bti\bin\bng\bg t\bth\bhi\bin\bng\bgs\bs
-
- Ok, you should now have DXSpider running nicely and allowing connects
- by cluster nodes or users. However, it has to be shutdown and
- restarted manually and if connection scripts fail they have to be
- started again manually too, not much use if you are not at the
- console! So, in this section we will automate both. Firstly starting
- the cluster.
-
-
- 4\b4.\b.1\b1.\b. A\bAu\but\bto\bos\bst\bta\bar\brt\bti\bin\bng\bg t\bth\bhe\be c\bcl\blu\bus\bst\bte\ber\br
-
- This is not only a way to start the cluster automatically, it also
- works as a watchdog, checking the sanity of DXSpider and respawning it
- should it crash for any reason. Before doing the following, shutdown
- the cluster as you did earlier.
-
-
- Login as root and bring up the /etc/inittab file in your favourite
- editor. Add the following lines to the file near the end ...
-
-
-
- ##Start DXSpider on bootup and respawn it should it crash
- DX:3:respawn:/bin/su -c "/usr/bin/perl -w /spider/perl/cluster.pl" sysop >/dev/tty7
-
-
-
-
- This line works fine for RedHat and SuSE distributions. The line
- required for Slackware distributions is slightly different. My thanks
- to Aurelio, PA3EZL for this information.
-
-
-
- DX:23:respawn:/bin/su - sysop -c "/usr/bin/perl -w /spider/perl/cluster.pl" >/dev/tty7
-
-
-
-
-
- This will automatically start DXSpider on tty7 (ALT-F7) on bootup and
- restart it should it crash for any reason.
-
-
- As root type the command _\bt_\be_\bl_\bi_\bn_\bi_\bt _\bq. DXSpider should start up
- immediately. You will see the output on tty7 and if you login as
- _\bs_\by_\bs_\bo_\bp you should find everything running nicely.
-
-
- So far so good, now to automate script connections...
-
-
- 4\b4.\b.2\b2.\b. T\bTh\bhe\be c\bcr\bro\bon\bnt\bta\bab\bb f\bfi\bil\ble\be
-
- Login as _\bs_\by_\bs_\bo_\bp and create a file in /spider/local_cmd called crontab.
- Edit it with your favourite editor and add a line like this (I have
- included a comment)
-
-
-
- # check every 10 minutes to see if gb7xxx is connected and if not
- # start a connect job going
-
- 0,10,20,30,40,50 * * * * start_connect('gb7xxx') if !connected('gb7xxx')
-
-
-
-
-
- The callsign involved will be the callsign of the cluster node you are
- going to connect to. This will now check every 10 minutes to see if
- gb7xxx is connected, if it is then nothing will be done. If it is
- not, then a connect attempt will be started.
-
-
- There are probably lots of other things you could use this crontab
- file for. If you want to know more about it, look at the DXSpider
- website at the cron page where it is explained more fully.
-
-
- 5\b5.\b. H\bHo\bop\bp c\bco\bon\bnt\btr\bro\bol\bl
-
- Starting with version 1.13 there is simple hop control available on a
- per node basis. Also it is possible to isolate a network completely so
- that you get all the benefits of being on that network, but can't pass
- on information from it to any other networks you may be connected to
- (or vice versa).
-
-
- 5\b5.\b.1\b1.\b. B\bBa\bas\bsi\bic\bc h\bho\bop\bp c\bco\bon\bnt\btr\bro\bol\bl
-
- In /spider/data you will find a file called hop_table.pl. This is the
- file that controls your hop count settings. It has a set of default
- hops on the various PC frames and also a set for each node you want to
- alter the hops for. You may be happy with the default settings of
- course, but this powerful tool can help to protect and improve the
- network. The file will look something like this ...
-
-
-
- #
- # hop table construction
- #
-
- package DXProt;
-
- # default hopcount to use
- $def_hopcount = 5;
-
- # some variable hop counts based on message type
- %hopcount =
- (
- 11 => 10,
- 16 => 10,
- 17 => 10,
- 19 => 10,
- 21 => 10,
- );
-
-
- # the per node hop control thingy
-
-
- %nodehops =
-
- GB7ADX => { 11 => 8,
- 12 => 8,
- 16 => 8,
- 17 => 8,
- 19 => 8,
- 21 => 8,
- },
-
- GB7UDX => { 11 => 8,
- 12 => 8,
- 16 => 8,
- 17 => 8,
- 19 => 8,
- 21 => 8,
- },
- GB7BAA => {
- 11 => 5,
- 12 => 8,
- 16 => 8,
- 17 => 8,
- 19 => 8,
- 21 => 8,
- },
- };
-
-
-
-
-
- Each set of hops is contained within a pair of curly braces and
- contains a series of PC frame types. PC11 for example is a DX spot.
- The figures here are not exhaustive but should give you a good idea of
- how the file works.
-
-
- You can alter this file at any time, including whilst the cluster is
- running. If you alter the file during runtime, the command _\bl_\bo_\ba_\bd_\b/_\bh_\bo_\bp_\bs
- will bring your changes into effect.
-
-
- 5\b5.\b.2\b2.\b. I\bIs\bso\bol\bla\bat\bti\bin\bng\bg n\bne\bet\btw\bwo\bor\brk\bks\bs
-
- It is possible to isolate networks from each other on a "gateway" node
- using the _\bs_\be_\bt_\b/_\bi_\bs_\bo_\bl_\ba_\bt_\be _\b<_\bn_\bo_\bd_\be_\b__\bc_\ba_\bl_\bl_\b> command.
-
-
- The effect of this is to partition an isolated network completely from
- another nodes connected to your node. Your node will appear on and
- otherwise behave normally on every network to which you are connected,
- but data from an isolated network will not cross onto any other
- network or vice versa. However all the spot, announce and WWV traffic
- and personal messages will still be handled locally (because you are a
- real node on all connected networks), that is locally connected users
- will appear on all networks and will be able to access and receive
- information from all networks transparently. All routed messages will
- be sent as normal, so if a user on one network knows that you are a
- gateway for another network, he can still still send a talk/announce
- etc message via your node and it will be routed across.
-
-
- The only limitation currently is that non-private messages cannot be
- passed down isolated links regardless of whether they are generated
- locally. This will change when the bulletin routing facility is added.
-
-
- If you use isolate on a node connection you will continue to receive
- all information from the isolated partner, however you will not pass
- any information back to the isolated node. There are times when you
- would like to forward only spots across a link (maybe during a contest
- for example). To do this, isolate the node in the normal way and put
- in a filter in the /spider/filter/spots directory to override the
- isolate. This filter can be very simple and consists of just one line
- ....
-
-
-
- $in = [
- [ 1, 0, 'd', 0, 3] # The last figure (3) is the hop count
- ];
-
-
-
-
-
- There is a lot more on filtering in the next section.
-
-
- 6\b6.\b. F\bFi\bil\blt\bte\ber\bri\bin\bng\bg (\b(O\bOl\bld\bd S\bSt\bty\byl\ble\be u\bup\bpt\bto\bo v\bv1\b1.\b.4\b44\b4)\b)
-
- Filters can be set for spots, announcements and WWV. You will find
- the directories for these under /spider/filter. You will find some
- examples in the directories with the suffix _\b._\bi_\bs_\bs_\bu_\be. There are two
- types of filter, one for incoming information and one for outgoing
- information. Outgoing filters are in the form _\bC_\bA_\bL_\bL_\bS_\bI_\bG_\bN_\b._\bp_\bl and
- incoming filters are in the form _\bi_\bn_\b__\bC_\bA_\bL_\bL_\bS_\bI_\bG_\bN_\b._\bp_\bl. Filters can be set
- for both nodes and users.
-
-
- All filters work in basically the same way. There are several
- elements delimited by commas. There can be many lines in the filter
- and they are read from the top by the program. When writing a filter
- you need to think carefully about just what you want to achieve. You
- are either going to write a filter to _\ba_\bc_\bc_\be_\bp_\bt or to _\br_\be_\bj_\be_\bc_\bt. Think of a
- filter as having 2 main elements. For a reject filter, you would have
- a line or multiple lines rejecting the things you do not wish to
- receive and then a default line accepting everything else that is not
- included in the filter. Likewise, for an accept filter, you would
- have a line or multiple lines accepting the things you wish to receive
- and a default line rejecting everthing else.
-
-
- In the example below, a user requires a filter that would only return
- SSB spots posted in Europe on the HF bands. This is achieved by first
- rejecting the CW section of each HF band and rejecting all of VHF, UHF
- etc based on frequency. Secondly, a filter rule is set based on CQ
- zones to only accept spots posted in Europe. Lastly, a default filter
- rule is set to reject anything outside the filter.
-
-
-
- $in = [
- [ 0, 0, 'r', # reject all CW spots
- [
- 1800.0, 1850.0,
- 3500.0, 3600.0,
- 7000.0, 7040.0,
- 14000.0, 14100.0,
- 18068.0, 18110.0,
- 21000.0, 21150.0,
- 24890.0, 24930.0,
- 28000.0, 28180.0,
- 30000.0, 49000000000.0,
- ] ,1 ],
- [ 1, 11, 'n', [ 14, 15, 16, 20, 33, ], 15 ], #accept EU
- [ 0, 0, 'd', 0, 1 ], # 1 = want, 'd' = everything else
- ];
-
-
-
-
-
- The actual elements of each filter are described more fully in the
- following sections.
-
-
- 6\b6.\b.1\b1.\b. S\bSp\bpo\bot\bts\bs
-
- The elements of the Spot filter are ....
-