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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
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