Electricity and You
(Most of the following was written by John, K7HB.—Ed.)
Some time ago I visited with a local ham that had a problem with his main radio power supply. As emergency communications folks, we all know that if you have three of something then you really have two, if you have two of something then you have a spare, and if you have only one of something –you really have none. He was at the point that he had none and could have been completely off of the air. However, he was prepared with chargers for some of his hand held radios and was able to keep a low power radio on the air. Under adverse conditions we can only do what we can and we sometimes have to revert to backup equipment.When he and I looked at his station I asked him if he had checked the fuse on the power supply. He said that his brother in law had and that it was good. So, in went a replacement supply and away went the failed unit.When I checked the failed unit’s fuse it was bad, it had been vaporized. Wow! If something vaporizes a fuse then it is a good bet that just sticking another fuse back in will not solve the problem.The Technician class just covered fuses and circuit breakers and the ARRL makes the strong point that a fuse should be replaced with the same current and voltage value as the original. That helps minimize the collateral damage to your house or radio shack if electronic components start melting and a 20 Amp transformer based power supply could do some serious melting.Which brought to mind a couple other electrical experiences over the last several weeks.A local ham had disconnected his antennas and unplugged the radio and lightning still managed to destroy one of his radios. Lightning can do funny things that are not so funny to those of us that receive them.For example, during the brief storm we had last week, the sideways rain, 60 mph + winds and lightening were bad enough that they prevented our hand held radios from reaching the 442 repeater! Usually we can do that easily but not during that storm. Also, despite houses supposedly being wired for safety our land line phone, microwave, and toaster oven stopped working –all at the same time.Lessons: have a spare for everything, use proper fuses and breakers, and if in doubt pull the plug out!(And from KJ4CMY—Ed.) I know personally of someone who had had a similar experience. He was a member of a local club. Lightning struck his house and destroyed a radio that had both the power and antenna unplugged. It is always a good idea to completely disconnect a radio while not in use. If a strong thunderstorm comes your way, it might be advisable to completely remove your equipment from the antenna and power inputs.
73 de
David Harden, KJ4CMY