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Author Topic: Attic Antennas...  (Read 2137 times)
KT0DD
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Posts: 284




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« on: November 15, 2011, 08:42:31 AM »

I am in an hoa situation. I read alot about attic stealth antennas for these situations. However, I was reading this warning on the TAK-tenna site:

Do not use or install TAK-tenna LLC products - or any antenna for that matter - indoor or inside ANY structure with RF energy ( transmitter ) applied to it due to HIGH VOLTAGE being on it - it's "NOT the watts" - and therefore a POTENTIAL FIRE HAZARD from SPARK!

Just how dangerous is this?

Todd - KT0DD
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K0YQ
Member

Posts: 533




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« Reply #1 on: November 16, 2011, 12:42:28 PM »

Hi Todd,

Check out Jeff AC0C on qrz.com, and his webpage.  Simply amazing attic setup.

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AE4RV
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Posts: 963


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« Reply #2 on: November 16, 2011, 01:01:40 PM »

Wow, AC0C's attic set up is mind blowing, very nice.

To the OP I'd suggest a simple fan dipole. They can be easily built, but I chose a commercial one. The Alpha Delta DX-EE requires only about 40 feet of space (less if you're creative) and gives you four bands: 10, 15, 20 and 40 meters. I have one in my backyard and like it.
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AF6AU
Member

Posts: 40




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« Reply #3 on: November 18, 2011, 02:05:34 PM »

A dipole is an impedance transforming device, low voltage, high amperage in the middle, high voltage and low current on the ends. If the end insualtors are too short and near metal, or the antenna wire is close to a metal object, you could create an rf arc, and with attic dust, insulation metallized foil etc. this is where the fire hazard is. Use decent insulated wire, and/or keep it away from metal (detunes it as well).

A loop antenna can work well too, and is less prone to arc, if you read the history of the cube quad, you will see why.

Also if you have a tile roof, a lot of tile has bit of iron wire and iron oxide as colorant in it. Mine does, and it makes a attic antenna attenuate signals so bad, it's terrible. I tried one, but the antenna(s) picked up every clock, catv box, and appliance oscillator in the house, but was lousy on HF 30m and up. Did a wondeful job triggering solid state light dimmers with CW. The whole house would flash with with the code.

Think of using a stealth outdoor antenna, a long wire antenna of 30 gauge wire is hard to see, and works if used with a tuner and a decent ground and/or a radial wire for each band connected to the tuner.  Making a night time tip up verticle that lays flat on the roof when unused, works too. Flag poles antennas work well too.

73's
AF6AU
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