Dissecting a Baofeng FM-V-U rubber duck antenna

I own a Baofeng UV-5R for more than a year now, it's a wonderful radio for the price and features, but of course it has it's pro and cons; but something that always puzzle me was the rubber duck that come from the factory with it.

In the Internet I read that the antenna it's a waste of time that you have to replace it with some other model, then you read else where that it works but get hot on TX, etc.

My personal experience was the first one: it won't work; it does but with marginal performance and only on FM commercial station receiving ;-), in 2m VHF I can't receive a friend in direct at less then 1 Km nor the local city repeater 4 Km away, I down have a UHF repeater or other signal to test with on 70cm.

But my Feidaxin FD-268A works happily with a modified Kenwood rubber duck (marked as 146-174 Mhz), also does the ancient Yaesu FT-23R with a BNC Alinco extra short rubber duck for VHF. The Baofeng  UV-5R works ok with either of the mentioned antenna (the BNC one, via a SMA to BNC adapter)

I'm on vacations and having nothing better to do,  knife on hand I get prepared to dissect the “subject”... done: in the following picture you have the results.

Subject antenna dissected, I removed a heat-shrink from the condenser to show it.

Let's talk about construction: it's a kind of shorted rubber duck!

Yes, the spring is at ground on the base of the SMA connector, and hot (center) part is brought to short via a 3pF condenser  with a extra long leg of about 1.5 cm counting the center part of the connector, then the other short part of the condenser is tin soldered to the 12th turn on the spring helix, that all.

But in my case the solder joint in the short leg of the condenser and the 12th turn  was broken, maybe that's why it won't work; let's fix that.

I have to say that this fault may be rather common because the 12th turn of the spring helix is about 4 cm from the base of the antenna, so there is a high chance that with the wear an tear it will fail, add that the condenser is a cheap ceramic one with 0.4 mm legs. The estrange fact was that mine was broken from the factory.

After fixing the solder joint I tested the antenna without the plastic cover, the results are ok, it works as expected and I can easily activate a distant (~50 Km) 2m repeater from my roof top with similar results as the other mentioned radios, so the antenna works with no apparent difference from the others.

And then, if you antenna work as expected it will get warm-hot to touch depending on the time you get with your finger on the PTT, the hot part of course is the base to 12th turns, aka the lower part of the antenna.

Ok, antenna fixed let's put back on the plastic cover... no joy.

The difference from the antenna at the air (no plastic cover) to the antenna with the plastic cover on is remarkably noticeable.

With the original plastic cover on, it's hard to activate the local repeater and I can't activate the distant one. Once I remove the plastic cover it works comparatively equal to the other tested antennas.

There is something wrong with the plastic cover of this antenna.

The conclusions to this is the same, if any of your Baofeng handhelds came with this type of antenna  replace it ride away to get trouble free operation; just I (and you) know now why this antennas are so troublesome.

Just google it and you will find a variety of antennas tested for the Baofeng UV-5R and others.

If you like to see a video of this procedure, see this by Remingtoncountry1100

Cheers and happy holidays.