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Author Topic: Tecsun PL-680 Sensitivity Tests  (Read 1412 times)

Offline VK3BVW

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Tecsun PL-680 Sensitivity Tests
« on: November 17, 2016, 2141 UTC »
I've had the PL-680 for a few months now. It has gone travelling with me and used in a variety of situations. This week I lined it up against a top HF transceiver - the Yaesu FTDX3000 - just to see how good this little radio really is in the sensitivity stakes! And I'm still impressed!! I've prepared a YouTube video which may be of interest, showing some side-by-side comparisons. You'll find it at:

http://medxr.blogspot.com.au/2016/11/tecsun-pl-680-sensitivity-tests.html

73 and good DX to you all,  Rob VK3BVW

Rob Wagner VK3BVW
www.medxr.blogspot.com
Yaesu FTDX3000, Kenwood TS2000, Yaesu FRG100, horizontal loop,dipoles for 80, 40 & 20m, Par EF-SWL Antenna,
BHI NEIM1031 Digi Noise Eliminating Module,
MFJ-1026 Noise Cancelling Module, MFJ and Tokyo Hi-Power ATU

Offline Token

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Re: Tecsun PL-680 Sensitivity Tests
« Reply #1 on: November 19, 2016, 0453 UTC »
Don't take this as a slam on your post and video, it certainly is not.  I thought the comparison was interesting and well done.  Also you specifically mentioned the ability of the FTdx-3000 to pull out signals in interference situations.  However sometimes new listeners, or people looking for guidance on receiver purchases, misunderstand such comparisons.

So a few comments for people new to the hobby.  This is not to be taken as disparaging of the Tecsun, several of their portables, including the 680, are exceptionally good for the price point.  If what you want is a portable with about as good performance as you can get for that price the 660, 680, and 880 are very good.

Raw sensitivity is seldom a problem these days, for any radio.  From the cheapest to the best, they will mostly have sensitivity within a few dB of each other.  What sets apart a good receiver from a so-so receiver are other features, such as dynamic range, close and far filter blocking, image rejection, etc.

That, unfortunately, can mislead new or inexperienced users.  They see tested or published sensitivities and filter widths (without understanding the need for more than one number to define filter performance) and assume that anything with the same filter width and sensitivity must perform about the same.

I had a new user tell me one time that he tried a specific portable against a top of the line contest rig, and that the portable could hear easily 90+% of the broadcast stations that the contest rig could.  And the portable was 1/100 the cost of the contest rig, so people would be stupid to buy the contest rig over the portable.  He did not understand that it is not the performance with the 90% of the strongest / clearest stations that defines a good radio, but rather the performance against the 10% of the weakest / most interfered with stations that shows how good a radio is.

As a general statement, if what you want is a receiver to pick up shortwave broadcast stations, several of the better portables out there will serve almost as well as a high end desktop radio.  It is only when you get into more exotic signals, or some of the really hard to catch broadcasters, that the desktops shine.

T!
T!
Mojave Desert, California USA

Offline VK3BVW

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Re: Tecsun PL-680 Sensitivity Tests
« Reply #2 on: November 19, 2016, 2158 UTC »
Thanks for your astute comments and advice to newcomers, Token. I largely agree with everything you have said. Just a couple of points:

  • The video was not aimed at new listeners, experienced listeners, or anyone in particular. It was just a series of observations relating to one particular receiver benchmark. And, given that the FTDX3000 has many advanced features not demonstrated in the video, it would probably be unfair to compare the two rigs on many other levels - the Yaesu would squash the poor little Tecsun in more sophisticated receiving tests!
  • I agree (....up to a point) that sensitivity is not so much of an issue these days. There are a few cheaper portable radios on the market that are as deaf as a post! With a few other Chinese rigs it can sometimes be hard to tell if this is because of poor receiver design or just uneven quality control. Some Etons, Degens, Grundigs, Kaitos, etc have had a mixed response from users. But, of course, some of these criticisms are based on either a) not understanding how to use the radio correctly, b) not understanding that an inbuilt whip antenna is a compromise antenna...at best, c) their expectations are not in line with the money they shelled out for the radio, or d) to a degree, it's all subjective anyway - the "beauty is in the eye (or ear) of the beholder" syndrome.
  • We know that some portables are just no good with an external antenna. A friend of mine has another Tecsun model (the model number escapes my memory for now). When we tested it with an external antenna, it was terrible....I mean REALLY BAD. It overloaded something chronic, with images everywhere, etc. It could only work on its internal antenna. We were surprised.

I agree with all your other comments. You don't need to spend big bucks to get a great radio (which, I guess was the main purpose of the video). BUT a customer DOES need to do research before venturing out into the marketplace with their wallet. And they need to know what to look for (part of the research bit).

Thanks for taking the time to watch the video and raising some very good discussion points.

Rob VK3BVW
Rob Wagner VK3BVW
www.medxr.blogspot.com
Yaesu FTDX3000, Kenwood TS2000, Yaesu FRG100, horizontal loop,dipoles for 80, 40 & 20m, Par EF-SWL Antenna,
BHI NEIM1031 Digi Noise Eliminating Module,
MFJ-1026 Noise Cancelling Module, MFJ and Tokyo Hi-Power ATU