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Victoria University Antarctic Research Expedition Science and Logistics Reports 1994-95: VUWAE 39

12 Radio Communications

12 Radio Communications

i)

Some of the radio equipment was ineffective under our field conditions. Communications on VHF via any of the repeaters was either marginal or impossible at our field camps.

The hand held booster antenna with which wo were provided would have helped at some sites (see below), except it very soon became inoperative. At the low temperatures, the coaxial cable became stiff and pulled out of the connector, where there is no satisfactory mechanical anchoring system to prevent this. Polyethylene coaxial cable which remains flexible to low temperatures is readily available and should be used for these applications.

Communications with our HF transceivers was necessary at three of our four field sites. However, communication with Scott Base was almost always poor or non-existent. We suspect that some of this was due to inadequacies at the Scott Base end since on most occasions we had good communications with other distant field page 12 stations (eg K061 and K044). However, the equipment was old (not a criticism in itself) and the battery lives were short. Most of the rechargeable batteries were clearly nearing their end.

The solar panels for recharging the batteries did not work efficiently at our sites. We either had frequent misty conditions or blown snow which covered the panels. Also the wiring and connectors were unsuitable for field conditions. Firstly, sufficient cabling should be provided so that the batteries can be left inside in the warmth. Secondly, the plugs and sockets should be such that they can be connected with gloved hands and there is only one way that they can be connected.

On the HF antenna, one lead was broken at a connector, and we had to repair it in the field.

ii)

Reception/transmission: Our sched times were at 0730 and 2000. They were generally satisfactory, except that at 0730, Alan would not have returned from McMurdo with the flight sched and we often had to arrange an alternative time.

At Table Mountain: From our campsite, we could not communicate with the hand held VHF sets. Communication on Channel 3 with the booster antenna was marginal. However the coax lead very soon pulled away from the connector (see above). Despite many attempts to repair this, no repair lasted very long. HF communication with Scott Base was also inadequate. Despite our taking care to optimise our antenna configuration, two - way communication was seldom satisfactory. In contrast, communication with K061, at the Renwick Gl was excellent.

By going 50 m up the hill, we could get reasonable communication with the hand-held VHF set. However, this was not very convenient, as at our 0730 and 2000 scheds, weather conditions were often very unpleasant.

At the low temperatures we experienced, battery life was short. Spare batteries were kept in our sleeping bags, but this was impractical for the bulky HF batteries. These 12V batteries, which were old, had very little capacity. The solar panels were ineffective, as for most of the time they were either covered in snow or we were in mist.

At Mt Feather: Here, at an altitude of 2500 m, looking down the Ferrar Gl. we could see Ml Erebus and could communicate on both channels 3 and 5. Our main problem here was with batteries running down. The solar panels were plastered with snow most of the time. By the end of our stay almost all our batteries were flat.

At Mt Crean: Here, we could communicate only with the HF sets. Communication with Scott Base was always poor, we had excellent reception with K044. Very often they had to relay our messages for us. Despite having another set of 12V batteries, They soon discharged and again the solar panels were ineffective. We discovered a site on a rise about 300 m away where we could communicate by VHF through channel 3. Without this discovery, we would probably have lost communications with Scott Base.

page 13

At Mt Lashly: Communications were possible only with HF. Transmissions to and from Scott Base were poorly received. We often had to rely on K044 to relay our messages. The most obvious shortcomings of the system were shown up on Thurs 8 December, when Gentle 11 landed with mechanical trouble. None of their on board transceivers could communicate with McMurdo. Communications with Scott Base via Our HF set were almost unreadable. Finally, by deploying their emergency HF set, Gentle 11 were able to get McMurdo, on a similar frequency.

Summary. For communications in the far field, the situation has deteriorated. In our previous Events at similar sites in 1978 and 1981, we used the same type of HF equipment as we were supplied for this Event. Communications then were generally better. The differences were that then we had two HF transceivers and the same batteries, but they were younger and we were provided with more of them. In these regions, solar panels cannot always be relied on for recharging the batteries. The HF communication system urgently needs updating.

iii)The efficiency of the operators was good. All our problems arose from inadequate reception.