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Equipment - Antennas My antennas are pretty simple, random wires and a discone for VHF/UHF listening. Our building's power is supplied via poles coming from the north side of the building (opposite where I am located luckily). Of course I do get plenty of the frying egg sound but I suppose it could be worse. Most of the noise I hear in the 10 - 15Mhz range, other than the usual background stuff, is some sort of (static?) buildup which gets louder and louder over a period of anywhere from 1 or ten minutes, then stays at that peak level anywhere between zero and 1 hour or more, then tapers off until gone again. The coax fed antenna doesn't suffer from this as much as the wire fed one. The random wires do perform well though, the furthest station I've heard was in Dakar, Senegal at the southern most tip of Africa, it's a French Navy station sending RTTY. I also occasionally hear Elmendorf AFB, Alaska and Hickam HF-GCS in Hawaii. Here is an image of my apartment and how the antennas are laid out: Random wire A is a 35 foot long piece of wire from Radio Shack's shortwave antenna kit, strung close to the ceiling against the wall. This one is using an impedance matching device I made from plans found on the web available here (PDF, 61Kb). The antenna is plugged into it through a banana type connector soldered to the west side of the antenna. On the other end of the box is a PL-239 connector which gets the coax feed line to the radio. I had to go with the less than optimal wiring path which takes both ground sides of the windings into the coax shield and the radio itself. Not much possibility of using grounding rods here. The author of the plans has tried this technique apparently and says it's not so bad, but I have a feeling it would be much better with a full grounding setup. I used the following items to construct the impedance matcher: #F-114-43 ferrite toroid (available from www.bytemark.com) 30 gauge wire PL-239 female panel mount connector Banana plug RS project case Some screws and plastic card stock (for toroid mount) Future floor polish (to seal toroid wire wrapping) Random wire B is a 43 foot long piece of wire from another Radio Shack shortwave antenna kit, strung along the ceiling. This one simply uses the feed wire from the kit to get the signal to the radio, soldered to the west end of the antenna and snaking around the walls to the radios. Currenty I have this one hooked up to the VR-5000. I'm still trying to figure out if I like the impedance box/coax combo, it kills some of the noise I hear on the other antenna, but it looses some signal strength at night for some reason. The wire fed VR-5000 generally hears more at night, however the R75 with this setup beats it by a mile on 11175khz during the daytime hours. Haven't quite figured out why... The discone is in use with the BC780XLT, and is of course fed through coax which was snaked through a hole in the wall. Not the best performance having it indoors, but for now I'll have to live with it. At least it's on the second floor which probably helps a lot. It is the older Radio Shack model bought in 1993, #23-5123 without the extra vertical element. With the discone I use a military surplus hi-pass filter with a 250Mhz cutoff which had been removed from some sort of equipment. It was a $20 eBay find. I should change the connectors on it so that I can have it at the antenna rather than at the radio. Currently the antenna coax gets to it through a PL239 to BNC adapter. On the other side of the unit is a tiny SMA connector going to a thin and short bit of coax (the kind used more for interconnects within equipment) which terminates into a rather loose fitting BNC connector to the scanner. Probably some signal loss there!

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