To assure proper operation of the
reflectors there are certain minimum requirements that connecting
nodes must meet
IRLP - Keeping the Radio
in Amateur Radio
To assure proper operation of the reflectors there are
certain minimum requirements that connecting nodes must meet. These
mandatory requirements are necessary to assure those using the reflector
do not receive unintentional interference from improperly adjusted or
No repeater tail or any other signal that may keep your nodes
COS high when no input signal is present to the node receiver.
This includes attempts to notch or turn down the audio on CW ID that still
results in a COS signal being sent to the IRLP network and thus an un-
modulated carrier on all connected nodes
No Courtesy tones or CW ID to the IRLP other than the occasional
CW ID that is overlaid with
a voice transmission due to someone transmitting over their local ID.
No pulsing of the node. This requirement has ZERO
tolerance for reason listed below
Pulsing is the single most important item we must prevent and is
also the most common reflector issue. Since it is difficult for an
offending node to detect this without being proactive, a node can be pulsing and
not know it.
A pulsing node is one that sends a COS signal to the IRLP network each time
another node stops transmitting. The result is that the pulsing node keys up
all connected nodes to the reflector each time the carrier of other nodes drop. If two pulsing nodes
are connected to a reflector at the same time, it grinds to a halt as the
two pulsing nodes will ping- pong pulse each other making the reflector unusable.
BUT HOW DO I ELIMINATE THE ID AND RPTR
The easiest way to eliminate both of these issues which almost always eliminates
pulsing is as follows:
Add a PL (CTCSS) Encoder to the repeater transmitter
Configure the encoder so it only sends PL when the COS
repeater receiver is a valid signal
Take your COS point on the link radio from a point where the
active state is only present with a valid PL tone
If you use the above interface your repeater courtesy tail and
ID will never be heard on the IRLP and chances are the default 150 mSec pulse
timing will do just fine.
HOW DO I KNOW WHEN MY NODE IS PULSING?
First of all run the PulseCheck utility outlined in the After
Document. After making the settings outlined there you should connect to the
Echo reflector and watch the green COS led on the IRLP board when the echo
transmission drops. If you see the COS led pulse or come on for any
duration you may be pulsing.
If mounting in the Linux box makes it impossible to see the LED
then do the following
Log into the node as user Repeater and then run 'readinput'.
This will monitor all node PTT and COS states as well as log any decoded DTMF
Make a test transmission to the echo reflector
As your node transmitter un-keys your screen should
If your screen displays
when the PTT ends - you are pulsing and need to determine why.
The above is to be considered mandatory requirements for
connecting to a reflector. Some reflector owners may have a more
relaxed position however you need to build to the above requirements to
assure 100% compliance.