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Both the Baofeng UV-5R handheld UHF/VHF radio and the Sainsonic AP510 APRS tracker come with interface cables with pirated chips. These are clones of Prolific USB/serial chips. Since Prolific has taken measures against this, only old drivers will work with them. That means that one has to stop automatic driver updates as explained on the Miklor site for the Baofeng UV-5R. The same is true for the AP510. This is a nuisance.

I got tired of this and got myself some USB/serial modules from Ebay based on the CP2102 chip instead. The cost was US $1.43 a piece so it should be affordable for anyone. I also got some clear heat shrinkable tube.

It wasn’t too hard to follow the instructions on the Miklor site. I ended up replacing the chip in the original Baofeng serial cable. I’m a hardware guy so I think it is a shame not to see the three LEDs for power, rx, and tx so I used my Dremel to make a 12×12 mm cut-out in the original case, and then I closed it by using transparent shrinkable tube. For a picture, see the top of the first image.

If it doesn’t work the first time, exchange rx and tx and see if that works better. According to this site, the boards can be marked just opposite of what you might think.

The Sainsonic AP510 APRS unit has a cable that on first sight just looks like a standard USB cable, but it also contains such a chip. Here I made a completely new cable without any case.  It is important that 5 Volts also passes through as this is used for charging. The pinout can be found on the site of DJ7OO (use Google translate if needed). I enclosed the board in shrinkable tube which is transparent enough for the LEDs to shine through as seen in the bottom of the first image. The board with the fake chip is found in the middle. 

So now I have interface cables for both units that don’t require me to stop updates of drivers or any other special precautions and it is much easier to program the devices from any PC.

Both the Baofeng UV-5R handheld UHF/VHF radio and the Sainsonic AP510 APRS tracker come with interface cables with pirated chips. These are clones of Prolific USB/serial chips. Since Prolific has taken measures against this, only old drivers will work with them. That means that one has to stop automatic driver updates as explained on the Miklor site for the Baofeng UV-5R. The same is true for the AP510. This is a nuisance.

I got tired of this and got myself some USB/serial modules from Ebay based on the CP2102 chip instead. The cost was US $1.43 a piece so it should be affordable for anyone. I also got some clear heat shrinkable tube.

It wasn’t too hard to follow the instructions on the Miklor site. I ended up replacing the chip in the original Baofeng serial cable. I’m a hardware guy so I think it is a shame not to see the three LEDs for power, rx, and tx so I used my Dremel to make a 12×12 mm cut-out in the original case, and then I closed it by using transparent shrinkable tube. For a picture, see the top of the first image.

If it doesn’t work the first time, exchange the rx and tx connections and see if that works better. According to this site, the boards can be marked just opposite of what you might think.

The Sainsonic AP510 APRS unit has a cable that on first sight just looks like a standard USB cable, but it also contains such a chip. Here I made a completely new cable without any case.  It is important that 5 Volts also passes through as this is used for charging. The pinout can be found on the site of DJ7OO (use Google translate if needed). I enclosed the board in shrinkable tube which is transparent enough for the LEDs to shine through as seen in the bottom of the first image. The board with the fake chip is found in the middle. 

So now I have interface cables for both units that don’t require me to stop updates of drivers or any other special precautions and it is much easier to program the devices from any PC.

The Nagoya VHF/UHF antennas made in China and available from sellers like 409Shop are popular and cheap, but I think they leave a lot to be desired in the quality control department.

A couple of years ago I bought a Nagoya NA-666 with a regular male SMA connector for use with my Kenwood and Yaesu rigs. I was impressed with the performance of this antenna, and with the fact that it achieved a true 1:1 SWR at bang on 145MHz.

So when I ordered another antenna of the same model but with a BNC connector to work with all my HTs (which have now all been fitted, where needed, with SMA to BNC adapters) I was surprised to find that its performance was a disappointment.

I am well aware of the existence of fake antennas on eBay and have bought more than my fair share of them, but this looked to all intents and purposes to be a genuine Nagoya (silver on black label on the base and a serial numbered Nagoya hologram on the pack.) It had been purchased from 409Shop, a reputable seller. However, when tested on my RigExpert AA-200 antenna analyzer the nice sharp SWR curve dipped to a minimum at 135MHz – 10MHz too low. The SWR at 145MHz was off the scale. Ho hum.

As any ham knows, if an antenna tunes too low in frequency the solution is to cut bits off. After a bit of a struggle the rubber end cap came off and I gingerly pruned about a tenth of an inch . The antenna analyzer showed the minimum SWR point had moved up 1MHz. So I carried on with the cycle of cut, test, cut, test until I had achieved a much more reasonable SWR at 145MHz.

Final SWR curve of the shortened antenna

As I approached 145MHz the antenna was now quite noticeably shorter and I was concerned that I may have passed the point at which the improvement due to a better match was counteracted by the reduced size of the radiating element. I may have passed that point but it is very difficult to make reliable and repeatable field strength measurements. Therefore I didn’t make the final cut which would have brought the SWR (shown above) to 1.0:1 at exactly 145MHz.

Field strength measurements and on-air tests led me to the conclusion that the 7-inch shortened NA-666 performed 2-3dB better than my 8.5 inch long NA-701. It beat all the stock rubber ducks by another 2 or 3 dB. The only antennas that outperformed it were a quarter wave telescopic (19 in long) an even longer Nagoya NA-767, a nicely made but unbranded “RH-770” and a “Diamond” RH-205 5/8 wave telescopic, all of which are really too long and cumbersome to use with a small radio like the Baofeng.

Using the shortened NA-666 I have had solid simplex contacts with 5 and 9 reports over distances of several miles and can even access a repeater 50 miles away from inside the shack. So I’m pretty pleased with the result.

The $3.79 antenna

Among users of the Baofeng dual band UV-5R HT a popular topic of discussion is what antenna to buy for improved performance. The general consensus sees to be that the stock Baofeng antenna is not much good. But no-one wants to spend $30 on a $40 radio to buy an antenna made by Diamond or Comet. The trouble is that half the antennas sold on eBay seem to be fakes that are about as much use as a piece of wet string.

A popular choice recently is known as the “$3.79 antenna.” This antenna – which also goes by the name “$3.42 antenna” after a recent price cut by one eBay vendor, has an SMA-F connector and a very flexible 6.5″ whip. It’s very similar to the Nagoya NA-666 but with a different base. You can find sellers by searching eBay for “female universal antenna for Kenwood”.

Both the Baofeng stock antenna and the $3.79 jobbie appear to be made by the same manufacturer. Printed round the SMA connector of the Baofeng antenna is the words “FM/136-174/400-480MHz”. The $3.79 antenna has the wording “FM/136-174/400-470MHz” in identical print but on a red not a black background.

UV-5R stock antenna

Despite the aspersions cast on the effectiveness of the UV-5R stock antenna, I found that it isn’t half bad. In fact, it is one of the most accurately tuned rubber duck antennas I have come across and performs remarkably well for a 12cm (4.5in.) long antenna. As the SWR plot shows, the VHF resonant point is exactly at 145MHz. I am unable to plot SWR at UHF but I can measure it at a fixed frequency and it was 2:1 at both 145MHz and 433MHz.

$3.79 antenna

The $3.79 antenna appeared to be tuned to 154MHz. The tuning is not as sharp as the Baofeng antenna and the SWR at 145MHz was just over 3:1. I measured a similar SWR at 433MHz. The actual SWR of handheld antennas will vary depending on whether the radio is standing on a desk, being held in the hand or worn on your belt so an SWR of 3:1 is nothing to be alarmed about. Even the best HT antenna will exhibit a poor match in some situations.

Measuring SWR can tell you whether an antenna is working as well as it should but it is no guide to on-air performance. After all, a dummy load will have a perfect 1:1 SWR and yet radiate nothing.

I measured the field strength of the signal radiated by the UV-5R at a distance of 1m using both antennas. I also tried a known genuine Nagoya NA-701 which is about the same length as the $3.79 antenna. There was nothing to choose between any of the three antennas at UHF. On 2m the $3.79 antenna was possibly marginally worse than the Baofeng UV-5R standard antenna. The Nagoya NA-701 was 3dB better, equivalent to doubling the transmitter power.

My conclusion after performing these tests is that buyers of the UV-5R (and the UV-3R which comes with an identical stock antenna) should save their money and use the antenna that came with the radio. To try to improve on this involves dabbling in the shark-infested waters of eBay and risking ending up with a worthless fake antenna that will need to be larger to give any improvement in performance. The $3.79 antenna is easily worth its price but it is 3 inches longer than the stock antenna and offers no significant improvement.

If you are a UK amateur and you like Chinese radios you’d probably never think of buying them from anywhere other than direct from China or Hong Kong, most likely using eBay. Ham radio dealers in Britain are widely regarded (rightly or wrongly) as rip-off merchants who work out the price by replacing the dollar with a pound sign and then adding on a bit more for good measure. Their pleas that the UK price includes VAT and the cost of providing a warranty usually fall on deaf ears.

In one of the discussion groups someone mentioned buying a radio from a British firm called Sinotel UK. I went to their web site and saw that they carried several models of hand-helds from China, including a new one I hadn’t seen before: a TYT UVF9 (pictured right.) But what particularly caught my attention was their prices, which were little more than what I have been paying buying on eBay. Their cheapest model, the Vero Telecom UV-X4 (similar to the Baofeng UV-3R) was just £29.99 (yes, a brand new dual band radio for 30 quid.) A UV-5R eas £34.99. The radio that had caught my eye, the TYT UVF9, was £47.99. It would cost me $68.50 from 409shop and I’d have to wait a couple of weeks for it.

I am not associated with Sinotel UK and have not even bought anything from them but if I want yet another Chinese handy to add to my collection I probably will.

I like my cute little Baofeng UV-3R+ though I find myself using its slightly bigger brother the UV-5R more often. Unfortunately the UV-3R+ has begun acting up with a fault that is difficult to fathom.

Quite often the UV-3R refuses to switch on. At first I thought that I had accidentally left the radio on and had depleted the battery, because I often do things like that. But the radio comes back to life if you remove and replace the battery or if you drop it into the charger for a few seconds. When I did this today the screen immediately showed a battery voltage of 4.0V which was expected given that it had been charged only a day earlier.

So the radio is failing to turn on even though there is plenty of juice in the battery. Like most HTs it has a “live” power switch and should turn on at the press of a button. The UV-5R on the other hand has a good old-fashioned rotary on/off volume control. Which, I now recall, was the thing that failed on my old Jingtong radio. Ho hum.

Back in February I bought a Baofeng UV-3R+. It came after an unusually long wait for products from China, in March. In that time, eBay vendors had begun advertising the new Baofeng UV-5R which had double the output power and a key-pad that could be used for DTMF. To add insult to injury the price of the 5R was less than I paid for the 3R+.

As the months passed the knowledge that the UV-5R could still be bought for an absurdly low price niggled away at me, until eventually I gave in and ordered one. Unlike its little brother the 5R got here in little more than a week. So now I have two Baofeng HTs. A ham can never have too many radios, especially at this price!

Baofeng UV-3R+ and UV-5R

After I sold my original UV-3R to make way for the Plus I had a few regrets. The original had the advantage of being lightweight and tiny. Although the Plus was only a few millimetres larger and a few grams heavier the difference felt more marked. It lacked the cuteness of the earlier model. But the drop-in desk charger was a nice standard accessory. The accessory port was the same as used by Kenwood and Wouxun, enabling some standardization. It is a nice little radio but functionally almost identical to the original 3R.

Baofeng UV-5R unboxed

The UV-5R is quite a big improvement over its little brother. It isn’t a lot bigger or heavier than the 3R+ but the extra size and weight gains you double the output power (4W compared with 2W) and a keypad which supports both frequency entry and DTMF. The latter makes the radio much more useful on Echolink.

The 5R feels solid and well built like the 3R+. In fact it feels like a radio that cost three times the price. I think Baofeng has hurt sales of the basic handhelds made by the Japanese “big 3.” Only rigs with ham radio specific extras like supporting D-Star or APRS will be able to justify a higher price. As neither of those things are useful for the typical Chinese business buyer of these radios I can’t see Baofeng starting to compete in that area. So Yaesu, Icom and Kenwood can breathe a sigh of relief.

Other things I like about the UV-5R are:

• 4W maximum power out
• Alphanumeric names for memory channels
• Backlit keypad – a classy touch
• DTMF – ideal for Echolink
• Analogue volume control with proper on-off switch .

I like the way the display (and keypad) lights up when a signal breaks the squelch and stays lit for a few seconds after the signal has finished. If you have more than one handie in use this feature lets you know which radio received the call. My Wouxun also does that.

There are a lot of other things to like, such as the voice announcement (my ham rigs don’t have that) and the fact that accessories and spare parts being really cheap. The same computer interface cable works with both Baofengs and the Wouxun. Headsets and speaker-mics work with two Kenwood radios as well.

Judging by the comments of some buyers in the user groups, “Baofeng quality” is still an oxymoron. You are taking a chance that the radio you receive will not have any faults. Sending the set back to Hong Kong But if you are prepared to take that risk (or pay a bit more and buy from a local dealer) then the Baofeng UV-5R is worth a lot more than you pay for it.