A good turn out resulted in a mixed bag of activities for Sunday. John ZL1OJ, keenly wanting to get going on HF, fitted a length of coax with PL-259’s.
After discovering the 5775 repeater still had a low but annoying beat tone noticeable at low receive levels, Keith ZL1BQE and Harry ZL1BK did some more investigation and hypothesizing. The tone was confirmed on the receive monitor speaker on the repeater. Padding the receive antenna port with an attenuator appears to stop the tone; it doesn’t appear though that there is a local external signal causing the problem, (the problem is reproduceable offsite) so another dimension to the puzzle.
Mark ZL1MRT demonstrating his Text over CW encoding system, that provides a self synchronizing text encoding algorithm utilising a subset of CW (EMITSO letters) to provide the data stream.
David ZL1DRV took to a processor PCB out of the Harris receiver, that had suffered from a leaky old NiCad backup battery. Using a fibreglass bristle brush, the corrosion and ruined solder mask was removed down to shiny copper. All ready for recoating.
Graham ZL1TOF and Martyn ZL3CK worked to further the emergency lighting.
Rob ZL4ROB demonstrated his HF mag loop that is under development. Rob is building a tuning capacitor for it, from scratch. A fascinating design that can work quite effectively inside a building.
