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A first look at the “last” Tecsun radio receiver? Tecsun’s PL-990: SW/SSB, AM, FM, and LW Synthesised DSP Powerhouse T ecsun Radios Australia recently submitted the latest iteration of Tecsun’s “flagship”, the PL-990 multiband portable for review. It is a most worthy successor to the PL-880 which has received many excellent reviews since its introduction almost a decade ago, and which we looked at in the December 2014 issue (siliconchip.com.au/Article/8203). We have noted some comment on the net that the PL-990 will be the last high performance multiband portable that Tecsun engineers will produce. Indeed, this is even alluded to on Tecsun Radios Australia’s own website. by Ross Why? We cannot find any explanation. siliconchip.com.au Is it because they believe they have extracted every last ounce of performance of this type of design with the PL-990? Looking at the specs and spending some time “hands on” you could easily be led to believe this is the case. There are other indicators that Tecsun have produced something pretty significant when it receives very favourable technical comparison reviews when put up against some of the world’s best brands. But when you compare them dollar for dollar, the Tecsun doesn’t just win, it wins hands down! But we’re getting ahead of ourselves – and Tester the only way that you would really be able to Australia’s electronics magazine July 2021  73 Tecsun-PL990 Specifications Frequency range and tuning step: Long wave (LW): 100-519kHz 9kHz steps (1kHz fine tuning) Medium wave (MW): 520-1710kHz 10kHz steps (1kHz fine tuning)         or   522-1620kHz 9kHz steps (1kHz fine tuning) Short wave (SW): 1711-29999kHz 5kHz steps (1kHz fine tuning) FM: Selectable – 64-108Mhz, 76-108MHz, 87-108MHz, 87.5-108MHz, FM tuning step 100kHz/10kHz Intermediate frequency: AM first IF, 55.845MHz, second IF 10.7MHz, third IF (DSP) 45kHz FM 128kHz Sensitivity/Selectivity: LW MW SW FM: 3mV/m 1mV/m <20µV <3µV 40dB 40dB 45dB 60dB Audio format: Supports 16bit / 44.1kHz WAV, FLAC, APE, WMA, and MP3 formats MicroSD (TF) Card up to 128G (not included) Can also pair to mobile phone (Bluetooth) Speaker: 4, 3W Power: Internal:      External: 3.7V (18650 rechargeable lithium battery) DC power supply: USB 5V current >1A judge for yourself would be to do your own A:B comparison. For many, that won’t be easy, so let’s see if we can help you out somewhat. The PL-990 It’s described as a “high performance shortwave radio”. Talk about damning with faint praise – it is so much more than that. For a start, it covers much more than shortwave, though that covers from 1711-29999kHz in 5kHz steps and fine tuning steps of 1kHz. Even with shortwave radio broadcasts not the force or quantity they once were (witness Radio Australia!) if it’s on the shortwave bands, the PL-990 will give you the best chance of finding it. Looking at the AM band, it covers 522 to 1620kHz in 1kHz fine tuning steps when set to the standard Australian 9kHz channel spacing. If you change it to 10kHz spacing (which is just a couple of button presses) that upper limit increases to 1720kHz. If you’re more into FM broadcasts, you’ve got a much greater range than the “normal” 88-108MHz. You can switch the lower limit to 64MHz, 76MHz, 87MHz or 87.5MHz, with a selectable tuning step of 100kHz or 10kHz. Admittedly, there’s not a great deal of interest below our 88-108MHz band – it’s mainly allocated to fixed and mobile radio, especially business and industry. But a lot of listeners get a kick out of . . . listening! And we believe some footy enthusiasts like to eavesdrop on the referee’s two way radio comms in this band. And for the masochists out there (oooh – wait for the screams!) it also covers the long wave (LW) band of 100519kHz, in 9kHz steps or 1kHz fine tuning steps. Especially 74 Silicon Chip here in Australia, there’s not a great deal to listen to down there – but you could have fun trying. OK, there are a few aircraft nav beacons “down there” and even an amateur radio allocation for CW enthusiasts. As you can see, it really does cover a huge slice of the electromagnetic spectrum. But wait, there’s more! If you find there really is nothing worth listening to, you can always listen to your favourite music saved to a micro SD (TF) card – up to 128GB – in 16-bit/44.1kHz WAV, FLAC, APE, WMA or MP3 formats. You can also plug the PL-990’s digital audio input socket into your computer via a USB-C lead (not included) and play music stored on your PC. Audio quality And that brings us to another of the PL-990’s strong points: its audio quality. Read any review or comparison and that’s one thing that’s always commented on: it just sounds great – much better than you might expect an off-air signal (or even recorded music) to sound. It’s hard to be objective about this – but subjectively, we were impressed. It doesn’t sound anything like your typical portable radio – the Tecsun engineers have really excelled themselves here! The audio amplifier is coupled to a wide-range speaker. It’s not stereo (why would you bother listening to mono radio?) but the combination works very well. If you DO want stereo sound, say from your micro SD card or perhaps FM stereo broadcasts, you have the choice of stereo headphones or line out for an external amplifier. Size All this is packed into 198 x 120 x 38mm – much smaller than most competitors. There’s nothing remarkable about the case – it’s functional and puts all the controls at your fingertips. Information is imparted by means of a relatively large (65 x 25mm) LCD readout. Weight, by the way, is about 620g. It’s powered by a single 18650 Tecsun-branded li-ion cell. Like all li-ions, it’s rated at 3.7V and this one is rated at 2000mAh. We’re delighted to see it’s not one of those ten thousand mAh cells you find on ebay and the like! (You know the ones – they don’t exist...) Price As you might expect, a premium product like the PL-990 doesn’t come cheap. It retails for $550, and that includes the radio itself, a faux leather carry pouch, 18650 battery, 230V “USB” charger and lead (of course, you can use the lead to charge it from your PC, car USB supply, etc etc), a long-wire “wind up” antenna and a pair of stereo ear buds. Naturally, instructions are also included but it’s just as easy to download a copy from the Tecsun Radios Australia website (www.tecsunradios.com.au) – that way you can search for what you want. For those who want to protect their investment, a deluxe version is available which includes the hard clamshell case shown opposite – this fits the radio inside its carry pouch. Performance The PL-990 has been receiving high praise for its SSB performance. When resolving SSB signals, especially those way down in the mud, it’s very important that the radio is Australia’s electronics magazine siliconchip.com.au Two versions of the PL-990 are available from Tecsun Radios Australia: the radio itself, a rechargeable 18650 lithium battery with charger/supply and USB charging cable, a wind-up external antenna and a stereo earbud set. This retails for $550. For those who want to protect their investment, the deluxe version includes all the above plus includes the hard clamshell case shown here for $635. able to not only receive, but allow you to understand what is being received! On the PL-990, the noise floor is very low and the SSB is very stable. Along with the choice of direct entry (pushbutton) or rotary tuning, the radio has a fine tuning control to assist you in resolving SSB (upper or lower sidebands). DSP (digital signal processing) of course is responsible for a lot of the performance. It does things the old analog circuitry didn’t have a chance of handling. FM performance is also very good, especially with that fine audio quality we mentioned earlier. AM, similarly, is right up there. Sensitivity on the FM setting is quoted as <3µV, while MW (AM broadcast) is 1mV/m. Unfortunately, even with its widest tuning range set, the PL-990 cannot get as far as the 6m or 2m amateur bands. LW is problematic: finding a signal worth listening to (especially in this part of the world) is not real easy – we’re not real sure why long wave is included in many radios these days! Longwave sensitivity is 3mV/m. As we mentioned earlier, shortwave (SW) signals are also much more sparse than they were a couple of decades ago. There are amateur operators, of course (the PL-990 can tune into all amateur bands between 160m and 10m), and despite the comments above, there are still many countries (did someone mention China) pumping out signals on the shortwave bands. You should find some signals around the 16m, 31m and 49m bands, although broadcasts can occasionally be heard in the 22m, 19m and 41m bands. Shortwave band sensitivity is 45dB. Selectivity is quoted as >40dB on the medium wave and long wave bands, >45dB on shortwave and >60dB on FM. We haven’t mentioned the PL-990’s IFs. It is a triple conversion receiver, with IFs at 55.845MHz, 10.7MHz and the third IF (DSP) at 45kHz. The FM IF is 128kHz. Undocumented features The PL-990 instruction manual is very comprehensive in the steps required to achieve a myriad of functions. But the radio has several features which are not documented in the instruction manual. Some of these, such siliconchip.com.au as the ability to turn dynamic noise reduction on and off, ability to change the muting threshold, ability to change the FM de-emphasis and even the ability to adjust the line output level to suit your amplifier, are detailed on www. tecsunradios.com.au We’ve seen other references to the same things on the net and we’re sure as more and more users discover more and more features, they’ll be promulgated in the usual ways. Conclusion We started out by saying this is a very worthy successor to the popular PL-880 receiver. Apart from the noticeable improvements, such as better stability on SSB, better synchronous detection, (arguably!) better audio quality (though this was/is one of the PL-880’s strong points), the PL-990 just seems to do everything a little better (yes, that’s subjective but that’s the way we see it). Add to that little things like switchable antennas (the external antenna socket, so essential for “proper” listening, now works on long wave, medium wave and short wave). Of course, it has the features you’d expect in a good receiver – a clock with twin timers and alarms (never miss that transmission you wanted to listen to! We’re pretty impressed by this radio. If you own an earlier model it might be time to update to this, the latest . . . and possibly the last! A bonus! For Australian and New Zealand customers, whichever version you order, Tecsun Radios Australia will also include a stylish Tecsun polo shirt to show your jealous friends you’re part of the “in” crowd – those who own a Tecsun! (limited sizes available) Contact: Tecsun Radios Australia Address: 24/9 Powells Road, Brookvale, NSW 2100 Web: www.tecsunradios.com.au SC Australia’s electronics magazine July 2021  75