Simple radial wire = new radio

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nanZor

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I can't believe it. For years I have purposely built all sorts of antennas for my radios, but when it came to portables, I got tunnel vision and just ignored some basics. My Grundig G3 is a new radio now.

Yes, I have built specialized antennas for the external antenna jack, but I often don't bring it with me, nor have the vertical supports, so when I'm out and about I'll just use it on battery-only and the built in whip. Results are just ok.

What I recently woke up to, and what the old-timers already know, is that when operating portable like this, half of your antenna is missing - that is, there is no rf-ground other than maybe 6 inches of circuit board. I'm also not carrying stakes around to pound into the ground when out in the park. :)

At home I don't have much of an rf-ground either since my ac lines are so noisy my wall warts are choked off with ferrites. Guess what? I just choked off the other half of my antenna as far as rf is concerned when using just the built in whip.

To get to the point, all I did for my G3 was to attach about 14 feet of thin #24 gauge speaker wire to the ground of the external antenna jack while still using the whip. Signals are up and the amplifier noise is down! Win-Win. Not to mention the fact that this amount of wire is easily just thrown on the ground or rolled up in the pocket. No magic length, just enough to get an improvement in the ground as far as RF is concerned.

I'm not using a mini-jack either, as that would disconnect the whip leaving me with nothing but the ground wire. I just folded over the ends of the 14 foot wire a few times to make a pressure fit just *BARELY* into the external antenna jack. I don't want to push it too far in so that it connects to the center conductor of the antenna jack - otherwise that would turn my wire on the ground into the radiating (receiving) element. I just want a ground connection and leave the whip active.

CAUTION!! DO NOT JUST START STICKING WIRES INTO YOUR ANTENNA JACKS! This could be a SAFETY HAZARD especially if you are running from AC. SERIOUSLY, DO NOT DO THIS if you are not familiar with your radio.

SAFETY FIRST. I can't over-emphasize this enough. Like sticking a Q-tip too far into your ear, you DON'T want to do this if it presents an electrical hazard or TRIPPING WIRE. Be thoughtful and safe about it. Pets, Children, the public, etc and yes YOU, come FIRST!

That being said, having just a little bit folded over for a slight pressure-fit into the ground of the external antenna jack allows it to be easily disconnected if you step on it so it doesn't crash the radio to the floor or trip others. Other than the electrical hazard if not done in a safe manner, you don't want to be a public nuisance with a TRIPPING HAZARD for the public or even animals that might come along and want to chew on it. Again, be SAFE.

This morning I was quite the radial-cowboy out in the park just throwing that 14 foot wire around on the ground with different positions for different directionality. For the most part I kept the whip in the vertical position. It was a lot of fun, and was an eye opener when I realized that although the whip on the G3 was small, it is still a vertical that needed a ground to complete the other half of the rf circuit.
 
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CLynch7

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Apr 13, 2009
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I've had very good luck using a tv balun, 300ohm terminals to a mono plug See:3.5mm Balun to Screw Terminal Transformer about halfway down the page. It is a standard 300 to 75 balun, one of the screw terminals is to the tip, the other is to the sleeve. Longwire is attached to the tip terminal, the ground to the sleeve. My ground is to a cold water pipe, I'm stuck on the 2nd floor. Works wonders.
 

nanZor

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Wow, that's the first one I've seen with a mini-jack on it. Neat!

I use the TV baluns for a number of things, but I do know that there is quite a bit of insertion loss below about 10 mhz or so depending on the build. Then again, if it allows one to make a better antenna than what you already have, right on!

Cold water pipe grounds are kind of iffy for me - when I was on the second floor here, the place was so new that the plumbing was mostly pvc inside the walls, so that didn't work out too well for me. Plus you've got plumbers tape and whatnot insulating the pipe elements from each other.

Still, it has worked for me in the past in older buildings, so good tip(s)!
 

CLynch7

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I'd been using it without the ground for a while, and it was ok, it started to lose sensitivity below 4mhz, and completely went out around 1200khz. With the ground, it works all the way down to 150khz. This house was built in the mid 60's, so it is all copper pipe, and the piece I'm grounding to goes pretty much strait down to the ground. FYI, my antenna is a 100 ft 'long'wire, oriented E-W, sloping from about 35 feet down to a 5 foot rod, with about a foot and a half strait down. I'm pleased with the results with my G3 (finally found a good one!) and G5, really wakes up my G6.
 
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