Weather Station Hardware > Weather Radios

Mono to stereo converter.

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You can try this to see if you can isolate the problem.

Unplug the radio cable from the computer and stream dead air. Then listen to the stream and see if the buzz goes away.

And for the hum, Google on Oddcast DSP plugins. Look for an equalizer (the more bands the better) or or maybe a notch filter. If your feeling lucky, try searching for Oddcast hum filter. Maybe you'll hit the jackpot.

What kind of antenna did you add to it?


--- Quote from: "SLOweather" ---What kind of antenna did you add to it?
--- End quote ---

I designed my own, replacing the monopole that comes with the radio.

According to my math, the optimal antenna length for 162.4 mzh is 1.846 meters. Since I can't put an antenna in the house that's 6 feet long, I opted for 1/4 the wavelength or 46 centimeters... that equals almost exactly 18 inches. So I got out the 10 gauge wire and made a loop antenna in the shape of an elongated recetangle, with the top and bottom lengths of 18 inches. I also made the length of the pole from the loop to radio 9 inches (or 1/8th the wavelength).

I'm certainly open to suggestions though... in fact, now that I have to working well, I might have to just brave the wife's temper and get a weather radio with a digital tuner.

You are correct that 1/4 wavelength is the correct length to use.

There are a couple of  easy, effective, inexpensive antennas you can build.

One suitable for outdoor use is to get an SO-239 connector from Rat Shack,
and 5 lengths of stiff wire cut to your 1/4 wavelength. Brazing rod works well, but even 12-14 ga solid house wire might work. Copper-coated welding rod will work for a while.

Also, 4 ring terminals and 4 screws and nuts that will fit through the holes in the terminals and those in the corners of the connector.

Solder one wire to the center pin of the SO-239. Crimp or solder the ring terminals on one end of each of the remaining 4 wires. Screw one to each corner of the connector, pointing out at right angles from each other. With the center element pointed up, bend the 4 down at about a 45 degree angle.

Then use a PL-239 cable to connect to the antenna, weatherproof it unless you're mounting in the attic, and figurre out how to mount it. One way would be to run the cable through a piece of thinwall conduit into which the PL-259 just fits.

That's called a ground plane antenna, and is great for a single freq application like a weather radio. Use care around those rod ends. In the past I've glued beads from the hoppby store onto them.

The second antenna is a collinear. Get a length pf coaxial cable like for a CB antenna. Strip off the outer jacket maybe an inch longer than your 1/4 wave. Be careful not to nick the braid.

Carefully pull the braid inside out back over itself down the cable until the insulated center conductor is fully exposed. Then you can put a layer of electrical tape or heat shrink over the braid. Form a small loop or eye in the end of the center cable for hanging. Yo could leave the insulation on and use a small double-wrapped zip tie to do it.

This antenna is harder to waterproof unless maybe you dunk the whole top in Plasti-Dip or something. It does roll up and become very portable, and again, is well suited for a single frequency.

Interesting read...

By the way, I went back to my original home-made antenna (just a simple loop, no measuring or optimization)... seems to work best of all.  :shock:


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