TNC-X – channel access behaviour

I have been investigating ‘lost APRS packets’, a result of many root causes.

One is a perception that when I drive in the local area, I often do not hear my own digi ‘echo’ yet I find that it did receive a packet and submit it to APRS-IS. This problem is much more apparent using a TNC-X that with any other KISS TNC in its place. Continue reading TNC-X – channel access behaviour

Does anyone assess to their digi / iGate performance?

During recent evaluation of a range of APRS servers and TNCs, I have inspected APRS-IS records and my own server logs to identify possible anomalies caused by the equipment under test.

In that time I have found defective records caused by digi / iGates: VK2JMA-5, Vk2YGV-5, VKWUWP-2, VK2UWP-1, VK2MPJ-1,VK2ZEN-5, VK2AMW-1, VK2RHR-1, VK2LKH-1, VK2MB-1, VK2BEN-1. Continue reading Does anyone assess to their digi / iGate performance?

The mobile APRS W2 digi left town this morning

APRS is characterised by a lack of standards or guidance, but mostly by a lack of compliance with those standards and a lack of understanding and common sense.

VK2UWP is travelling around the countryside and from the look of it, setting up a WIDE2 digipeater in the local caravan parks without regard to its dysfunction. Continue reading The mobile APRS W2 digi left town this morning

TNC-X – DCD behaviour

I have been investigating ‘lost APRS packets’, a result of many root causes.

One is a perception that when I drive in the local area, I often do not hear my own digi ‘echo’ yet I find that it did receive a packet and submit it to APRS-IS. This problem is much more apparent using a TNC-X that with any other KISS TNC in its place.

A possible explanation is that it did echo but I did not hear it due to collision with another digi.

So that led me to explore whether TNC-X fails to quickly detect the other digi already transmitting. Continue reading TNC-X – DCD behaviour