Noise. While on St. John we had an exceptionally quiet location. I was able to hear signals that didn't move the meter and that was very nice indeed. This was not the case on Montserrat. I'm not sure if the problem was extant that first night but certainly by the second day there was this buzzing noise that would walk through the bands occasionally. My guess: one of us had some device, a battery charger, charger for our shaver, clock radio, something, that was generating this noise. I never figured it out but it vexed me for most of the time I operated at the villa.
When I first noticed this irritating S9+ signal through my headphones I started looking for suspects. My first thought was the fancy battery chargers used to charge the packs used by Budd, Chris, and the other fellows during their portable operation. These units were set up on the table next to our operating position and, well, it seemed like a good bet that they were making some noise. We unplugged them. The noise remained.
We should have had a plan for noise location and abatement. We didn't. Again, we had a hole in our planning process. Here are some guidelines I have for next time:
- Check gizmos for noise before you leave - This probably sounds obvious, but I'll list it anyway. If you are planning on taking something on a trip, check it out before you leave. Don't just make sure it works. Make sure it works without generating all sorts of HF hash. Put a receiver next to the device and power it. Does it buzz? Make sure, if the device has different "modes", that each mode is quiet. Perhaps a two-stage SLA charger will be quiet during the main charging cycle but noisy during the trickle charge, for example.
- Unpack and deploy electric devices systematically - I can't be sure if the noise problem on Montserrat was something preexisting in the villa or if it was something we brought with us. Seven guys unpacked and started plugging in every manner of device imaginable: battery chargers for radios, cameras, camcorders, iPods, cell phones, and who knows what else. I tried to organize an "unplug this thing and see if the problem goes away" search, but it was only half-heartedly executed. It is better to narrow your list of suspects by plugging in a few items then seeing if you have a problem rather than plugging in everything and hunting for the problem afterwards.
- Ferrite - If you do manage to discover, for example, that a particular wall wart is the culprit, it would be nice to be able to do something about it! I brought a small bag of snap-on ferrite for that purpose. Even on a 100 pound DXpedition, the benefits of having these things outweighs the costs in, well, weight. They are worth bringing.
- Time shift - If you have some device that generates RF hash that you can't live without, see if you can use it when you are not operating. If this is for you, the ham, then that's probably easy. If this is something near-and-dear to somebody else on your excursion (such as your XYL), you'll need to be diplomatic and negotiate something. Hopefully, you can minimize the time overlap between the hash generator and your DXing.
Sometimes the noise is outside your area of control. Dave sent me a pointer to this article discussion noise problems with overhead lines on St. Kitts. I certainly hope this sort of things won't affect me this fall!