Year Introduced: 1997
Power: 12 volt DC (mains power included)
Size: 18.5 by 19 by 6.5 cm
Weight: 1800 g
Coverage: 30 kHz - 30 MHz
Value Rating 3/5
The top end of the short-wave receiver market
has slowed in the last twelve months. Sets costing over US$1000 have
been particularly hit, partly because many of the cheaper portable
receivers have introduced a lot of new features which attract more
general users, especially those experimenting with international radio
listening for the first time.
In Britain, one manufacturer has taken a
different approach. AKD, a company based at Stevenage in Hertfordshire
has come on the market with what they call the Target HF3
communications receiver, priced at £160, including VAT.
Bearing in mind that entry level communications receivers such as the
Lowe HF-150 costs £419 in it basic version, or the Yaesu FRG-100
for around £470, the AKD is clearly very much cheaper. Now that
the units are in production, we have been testing one for the last
8 weeks, doing quite a bit of both practical listening as well as usual
standard measuring scheme.
The first thing that strikes you as you unpack
the radio is that it is extremely compact. That's partly because the 12
volt power supply is not inside the set, but comes as a brick-style
power pack which you plug into the wall. You plug the jack into
the back of the radio, connect an external antenna, and the radio
is ready to perform.
The front panel is extremely simple. There's a
large liquid crystal display showing the frequency, four little
pushbuttons, two rotary controls, one marked volume, the other marked
clarify, and a large tuning knob. In fact the tuning system is
extremely simple and handy to operate. The tuning knob has a
weight inside so it has a nice feel to it.
The coverage is from 30 kHz to 30 MHz in one kHz
steps. If you turn the knob slowly then you move in one kHz steps. If
you turn it faster, then the steps get progressively larger -- 10,
100 or even 1000 kHz -- at a time. So if you need to, you can hop
from one end of the band to the other in a very short time. One
kHz steps is fine for most broadcast applications, but if you're
going to use the set for listening to utility stations, then the
"clarifier" control allows you to tune finer than 1 kHz. However, these
slightly changes in frequency are not reflected on the Liquid Crystal
Display. The receiver is dual conversion. The first intermediate
frequency is at 45 MHz, the second at 455 kHz.
You can use the set for listening to broadcast
stations in AM, or switch the mode to either USB or LSB. You'll need
that if you want to monitor traffic on the amateur radio bands.
The HF3 has just one memory channel, which also remembers the
mode. When you switch the set on, this is the channel that is
recalled. If you tune around a bit, you can go back to this channel
again by pressing the recall button. But that's it.
We tested a version which has a built-in board
to allow you to connect up a home computer for decoding
weather-facsimile signals. That's quite neat, but it means that on
this version you have to forfeit the output for a pair of
headphones. It is present on the standard version. That's something you
can live with. But we were surprised that in an effort to keep the
down, AKD has used an ordinary hi-fi phono cinch plug for an aerial
socket. You find this type of plug on the back of audio equipment, but
not on radio receivers.
We don't understand why AKD didn't use a
conventional SO-239 socket which is much stronger. Most ready made
antennas come with a plug that matches, so it's a shame that you
have to solder on a phone plug instead. This is mechanically,
probably the weakest point of the receiver and within a few days
of use it had worked loose on our test example.
AKD does supply a length of 10 metres of wire
with a phono plug already soldered onto one end. But this is not the
best solution for short-wave listening. If you put the antenna up
the average house, it is almost guaranteed to pick up a lot of unwanted
noise from apparatus inside the house, such as fluorescent lights,
thermostats, computers and TV's. We used an external antenna with
a Magnetic Balun, mounted 5 metres away from the building, with a
coaxial cable feeding the signal into the shack. The background noise
was considerably quieter this way. We also experimented with an
active antenna mounted outside, well away from the house.
The radio is very well constructed. If you look
inside the HF3, you'll find that it is logically laid out and built to
last. The PLL synthesiser is shielded inside a separate box to keep the
noise away from the sensitive input circuitry. But the outer casing is
made of durable plastic which is not shielded.
So now to some of the receivers specifications,
starting with sensitivity across the range between 30 and 30,000 kHz.
were measuring the point for 10 dB signal to noise at 60% modulation,
which is equivalent to an AM station that is just intelligible. In
practice, 20 dB signal to noise was needed for acceptable
listening, using the 6 kHz filter. Between 50 kHz and 15 MHz, the
sensitivity is quite constant, hovering around 2.5 microVolts. Above 15
MHz, the sensitivity drops, so that you need between 3.5 - 4.5
microVolts to get the same level of intelligibility. In the SSB modes,
the receiver is roughly three times more sensitive, which is to be
Those figures for sensitivity are only fair, but
remember that below 10 MHz, a receiver doesn't have to be too
In this region, the antenna will provide more than sufficient signal to
drive the radio. Above 15 MHz, the fair sensitivity of the set is
noticeable, especially if you live in low signal strength areas like
West Coast of North America or in the Pacific
The designers of the HF3 have done this to
reduce the problems of overloading. Remember that a huge number of
signals are presented to the front end of the receiver, and the
task of any radio is to pick out the wanted signal and reject the
rest. The more sensitive you make a radio, the more you have to
invest in circuitry to ensure that strong signals don't overload the
front end of the radio. Once this happens, weak stations disappear into
the background noise, suppressed by local powerhouse broadcasters using
500 kW or more.
difficult to access
There is a two-position attenuator on the back
of the radio. If you switch it on, signals are attenuated by a factor
4, in other words by 12 dB. That's quite coarse, and operation is
complicated by the fact that the attenuator is on the back of the
If you can pick up a fine step attenuator at a ham radio store, you'll
find that being able to try something like 6, 12, or 18 dB of
attenuation is quite handy. In practice, you're trying to find the
balance between letting too little signal into the receiver and
The signal strength metre is in the form of a
bar graph on the liquid crystal display and in fact is only a rough
guide to signal strength. There are 10 segments, one of which is
always lit. We found it was easier to use your ears than use the
tuning metre as a guide.
The receiver has two bandwidth filters
installed. For AM broadcast use, the best results are obtained with the
6 kHz filter. We would have chosen a slightly narrower filter for AM
use, since shortwave stations are spaced 5 kHz apart in practice.
This results in sideband splatter if you´re listening to a
weak station that is 5 kHz away from a strong station. For SSB and
facsimile, a 3.8 kHz filter is installed, but you cannot use this for
the AM mode. The selectivity of both filters turns out to be quite
especially for a set of this price category.
The selectivity of the HF3 is contrasted by the
limited dynamic range of the receiver. The budget design of the HF3
shows through here. In single sideband, two signals, each of 1.3
milliVolts and spaced 50 kHz apart, produce a 1 microVolt
intermodulation spurious product. This unwanted signal gives 10 dB
signal to noise ratio and can thus disturb reception of a desired
signal. These figures are equivalent to a third order intercept point
The limited dynamic range is also a problem with
AM broadcast reception. To give an example. The receiver is tuned to a
station of moderate strength (6 Signals stronger than 50 dB than the
desired signal start to overload the receiver. So in practical
terms the dynamic range of the HF3 is only 55 dB, 72 dB in SSB.
Any reasonable antenna is capable of providing sufficient signal
to overload the radio, especially here in Europe, after dark, on
bands below 10 MHz. In AM, we measured a third order intercept point of
around. That's about the same sort of results we measured on the
R-600 ten years ago.
AKD have put a decent audio amplifier inside the
HF3. It sounds quite pleasant. It delivers half a watt RMS into a
loudspeaker, with less than 1% distortion, which is more than
for more listening purposes. Remember that only the standard model
has an output for headphones.
If you plan to use to set for unattended
monitoring, try to pick a place with a fairly constant temperature. We
found that at a stable room temperature our example wandered about
plus or minus 30 Hz during a listening period of a few hours.
That's not a problem with AM reception, but it's a bit more critical
telex reception. If you use the set in an outside shack where
temperatures are more variable, then the receiver wanders by as much as
200/300 Hz over a period of few hours.
In conclusion, we did quite a bit of listening
with this receiver. During the day, using a good 15 metre long external
antenna**, we found the set pleasant to use. It was great for general
broadcast reception and was able to decipher at least some of the
stronger amateur radio transmissions on 40 and 20 metres. In the
evening though, listening around 14 MHz, we had severe problems
with broadcast interference from 15 and 11 MHz. Attenuation helped
a bit, but not that much.
The bottom line is that this set is a great
entry-level receiver for the shortwave broadcast listener. You get what
you pay for. If you pay three times the price for a communications
receiver, you will get noticeably better results. Remember too that
of the portable sets like the Grundig Satelliet 700 will give similar,
if not better short-wave performance and they have FM reception and
memories. On the other hand, the HF3 from AKD in the UK is easier to
tune, well built and sounds better than many portables. It fulfils
a need in the European market place.
In the UK, the set costs £160 including
VAT. Outside the UK, the set is more expensive, costing around
€250 here in The Netherlands. That's of course because of import
duty and transportation costs. The HF3 is made by AKD, Unit 5,
Parsons Green Estate, Boulton Road, Stevenage, Hertfordshire, SG1 4QG,
UK. AKD can also be contacted by fax. The number is 44 for the UK, then
The Lowe-badged version - the SRX-100 - is sold
in overseas markets where AKD does not have any presence.