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A new, high performance DSP BCL radio receiver . . . aimed squarely at AM listeners! The Tecsun S-8800 Although it is a multiband receiver, covering shortwave (with SSB), long wave and FM (way down to 64MHz), it’s the long-neglected AM radio listener that this new release from Tecsun Radios Australia is obviously aimed at. W hen we say long-neglected, it’s true: manufacturers seem to have gone out of their way to improve reception for FM listeners and even provided many more “bells and whistles” for short wave and even long wave enthusiasts. But to a large degree, AM reception has been much siliconchip.com.au the same for many years. And that’s a pity, because despite what you might think, AM radio hasn’t lost much (if any) of its popularity and many listeners, particularly in “the By Ross Tester bush” have been crying out for a decent AM radio. They might just have one with the Tecsun S-8800. It’s not a cheap set – with a recommended retail price of $349, you’d expect pretty good performance. Early tests in fringe AM listening areas (eg, July 2017  57 anywhere any distance from a transmitter!) suggest that the S-8800 is right up there, even exceeding many higherpriced sets in its ability to not only resolve distant stations but to maintain them at an enjoyable level. OK, what does it offer? The first thing you’ll notice when you unpack the box is the infrared remote control. What’s that? A radio with a remote control? Unusual – but it’s a bit of luxury for the user. All functions can be controlled via this remote so you don’t have to get up from your favourite armchair to, for example, increase the volume! It will also allow you to turn the receiver on and off, change bands, scan (either memories or the band) and even let you enter frequencies directly via the keypad. Another major departure from most receivers is the inclusion of rechargeable lithium-ion batteries, as distinct from the AA, C or even D cells most use. So you won’t be forever buying new batteries – the two 18650 cells are Tecsun’s own brand and are rated at 2000mAh, so should give you long listening! It draws around 75mA turned on (depending on volume, of course) or about 80uA when turned off. Recharging is achieved by plugging in to any “USB” source (eg, a computer or a USB power supply [not included]) via a mini-D USB socket on the rear. The adaptor cable is included. You can also run the radio from a 5V/300mA external DC adaptor – but be warned, most “switchmode” plug- SPECIFICATIONS FREQUENCY RANGES FM: 87-108 / 87.5-108 / 76-108 / 64-108MHz (Tuning Step 0.01MHz / 0.1MHz) SW: 1711- 29999 kHz (Tuning Step: 1kHz / 5kHz) MW: 522 -1620 kHz (with 1kHz / 9kHz tuning step) 520 -1710 kHz (with 1kHz / 10kHz tuning step) LW: 100 - 519kHz (Tuning Step: 1kHz / 9kHz) SENSITIVITY FM (S / N = 30dB): <3μV MW (S / N = 26dB): <3mV / m LW (S / N = 26dB): <5mV / m SW (S / N = 26dB): <20μV SSB (S / N = 10dB): <3μV SELECTIVITY (Factory default of AM IF bandwidth is Narrow Band) FM: >35 dB (± 200kHz) MW/LW: >40 dB (± 9kHz) SW: >40 dB (± 5kHz) S/N RATIO FM: MW/LW: SW: IFs SSB, AM FM: >5dB >40dB >45dB 1st IF: 55.845MHz 10.7MHz FM STEREO CROSSTALK:    >35 dB OUTPUT POWER (distortion 10%): 450mW pack adaptors will introduce an intolerable amount of noise. If you can find one, choose a linear (ie transformer) supply – or simply charge the batteries regularly. Incidentally, the infrared remote control uses standard “AAA” batteries, not some high-priced button cells. We’ll gloss over the longwave (LW) The display on the S-8800 doesn’t show much . . . but it shows enough! 58  Silicon Chip 2nd IF: 10.7 kHz section of the receiver because there’s not a great deal to listen to down there (unless you’re into aircraft beacons. . .). Longwave is used a lot more overseas, particularly Europe, and because of the characteristics of this band, you might be able to tune into some of those stations from time to time. The shortwave (SW) and FM bands are much more interesting to Australian listeners, with a range of interesting stations on the shortwave bands including amateur operators (you’ll find them around 1.8, 3.5, 7, 10, 14, 18, 21, 24 and 28MHz), older 27MHz CB radio (which often isn’t worth listening to!) along with emergency, business and commercial users. Finding them can be a bit of a “hit and miss” affair but once found, you do have the luxury of being able to store up to 650 stations in memory. The shortwave section covers just above the broadcast band (1.711MHz) through to almost 30MHz (actually 29.999MHz and with its single sideband plus AM reception, along with fine tuning, you’ll be pulling in stations that you didn’t know existed! FM is quite different to what you might expect. As well as the FM broadsiliconchip.com.au Rear and side views show there aren’t a huge number of controls – most of the work is done by the receiver itself. On the back you have connectors for antennas and a mini-USB charging socket, while the side has switches for internal and external antennas, DX and local reception plus stereo (on FM) headphone socket and line outs. cast band (88-108MHz) you can also tune in as low as 64MHz. In this 6488MHz “slot” there’s quite a lot of twoway radio used by all sorts of businesses and organisations. Both the FM and SW bands can be significantly enhanced by the connection of an external antenna; provision is made for this on the back panel via a BNC socket. AM reception As we noted at the start of this review, AM (amplitude modulation) is where the Tecsun really shines. There are two major features required of a good AM receiver – excellent sensistivity and excellent selectivity. The first mainly refers to the radio’s ability to pick up very weak stations. Selectivity refers to the radio’s ability to differentiate those weak signals from those (perhaps stronger) on adjacent channels. Another important characteristic is frequency stability – it’s one thing tuning in that elusive, faint station – the last thing you want is the receiver “drifting” so you lose it. Overlaying all this is the fact that the Tecsun offers Digital Signal Processing on the HF band so you virtually have the power of a computer to help you enjoy listening. In deep fringe areas, far outside the “normal” range of AM radio stations, the P-8800 consistently outperforms other receivers, even those costing siliconchip.com.au considerably more. One feature which long-distance (or “DX”) listeners will enjoy is the AM bandwidth switching. When an AM signal is noisy, being able to adjust the bandwidth from 6kHz down to 3kHz, or even 2.3kHz, can mean the difference between annoying noise and an intelligible signal. Reduced bandwidth does have a cost, of course, and that is reduced fidelity. But if there’s a choice between receiving a station or not, it doesn’t really matter! You also have the choice of channel spacing. Here in Australia, AM stations are 9kHz apart, so that is where you’d normally have the switch set. But if you’re listening to some overseas DX, you might want to change to 10kHz spacing. This has another benefit: you’ll extend the normal range of 520-1620kHz up to 520-1710kHz. You can step through the dial in 1kHz steps, if you wish. Like the FM and SW bands, the AM band can be rather siginificantly enhanced by connection of an external antenna (again, connections on the back). The difference is that the AM external antenna input is high impedance, so a “long wire” antenna is ideal. While (theoretically) an AM antenna should reflect the frequency you want to listen to, there’s an old bushie rule of thumb: as high and as long as you can make it! If you do get into trouble with too much signal (maybe from a local radio station), there is a local/DX switch to attenuate it. While we’re talking about sound quality, the Tecsun S-8800 offers 2W of audio output, driving a relatively large – for a radio – speaker (40mm). You won’t suffer for lack of volume – and there are bass and treble controls to tailor the sound the way you want it. And remember, all these functions are available on the remote control. One thing we haven’t mentioned is its size. It’s no hand-held, at 192(W) x 113(H) x 33mm (D), and weighs just over half a kilogram without batteries. And we almost forgot – the Tecsun also sports a clock with various alarm functions on its large, easy-toread LCD display. So there it is: a great performer on LW (for what it’s worth), SW and an extended FM band. But an outstanding performer on AM with a range of user controls and functions to make listening a pleasure, rather than a chore. If you live in, or go “bush” and want a radio that will let you keep listening where other radios have given up, or if you’re a city resident who wants to give DX listening a go, try the Tecsun S-8800. Where from: Tecsun Radios Australia Unit 24, 9 Powells Road, Brookvale, NSW 2100 www.tecsunradios.com.au SC July 2017  59