Maurice ZL1MPU and Dave ZL1DL were having a conversation on the 5775 repeater on Thursday afternoon when the repeater remained triggered from around 13:40. It appeared that the problem was a transmission on the input frequency as there was some apparent low level audio detectable: fan noise, hum and some sort of background activity appeared to be present. The repeater then went off the air. Maurice and Dave proceeded to MP to investigate the issue.
After determining there was no problem with the repeater – it had simply timed out on transmit overtime. As the interfering signal was still holding the squelch open, the transmitter remained “timed out”. The repeater was then turned off, to aid in finding the offending signal.
So attention turned to tracking down the source of the triggering signal. The signal level on the repeater input frequency was indicated as full scale on the club FT-7800. Other signal levels from assisting parties across Auckland and Waiheke, were reporting the signal strength as relatively lower. A scan of the MP building showed no local source of the interference, so an attempt to pinpoint the direction of the said signal was made. A Baofeng with its standard rubber ducky was the only portable radio equipment immediately available. With no directional antenna available, Dave held the radio, with squelch disabled, close to his chest while turning 360°, at the same time listening for a change in signal / noise level. From two locations; top of the tower and the west deck, there was a definite signal peak to the West.
At a point in time, some background utterances in the form of “unrepeatable flowery language” were heard, multiple times as well as children’s voices announcing they “had arrived home”. This suggests the transmission may have been unintentional. The transmission ended more than two hours after it started. The 5775 repeater was then brought back online.
Thanks to everyone who pitched in to help track down the source of the signal, Who says fox hunting isn’t fun?