Hi team,

My company has recently acquired a WiSpy DBx to troubleshoot WiFi problems at a customer of ours, and the other day I had a 'field day' with it, what a great tool!

The customer is truck company, and they were/are having problems in a truck service garage with a wireless network, and with a wireless diagnostic system used for maintance procedures.

The wireless network with problems is the 'internal 1' network on channel 1 in the picture attached. It shares channel 1 with a external WLAN with a hidden SSID. Several stationary source of interference were easily found (including a wireless 'wheel-lining up' device used by the next door tire fitter, this is the spike just before channel 1). However, everything worked in the presence of these sources, so they were not the main cause of the problems.

We ran WiSpy for several days, and used pingplotter to determine when there were connectivity problems. A few days went by without any packetloss, when suddenly there was a half-hour period with very erratic performance on layer 3. Zooming into the Chanalyzer recording at that time showed the picture attached. With this image in mind, I looked at the data recorded earlier, and found the same pattern occuring every day at around the same time, even though it didn't lead to packetloss in our pingplotter probe.

It seems someone in the neighborhood runs a big machine or a transmitter of sorts from around noon until 3-4 pm, causing a very regular interference pattern across the entire spectrum (although not as pronounced in channel 12 and 13). Does anyone have any idea what this could be? There are mainly automotive businesses in the area, a tire-shredder next door (runs his shredders 8 hours a day, so doesn't fit the bill), a tire fitter, an office, a fuel station, a dealership, etc. <div style="text-align: center">[img]/files/images/storing_notes.preview.jpg[/img]

In the meantime we have moved the 'internal 1' WLAN to channel 13, where it so far appears to work without problems. The exact problems with the diagnostic tools aren't clear yet, as the technicians haven't actually tried to use it in a long time, and every time I watched over their shoulder it worked fine.

Any input would be appreciated,

Thanks in advance,

Regards, Anne