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“Degen” Synthesised HF Communications Receiver Review by Ross Tester Elsewhere in this issue we feature “WinRadio”: a very high performance, computer-based radio receiver. As that review was being written, this tiny communications receiver also arrived at SILICON CHIP. It’s very significantly cheaper, covers the complete 100kHz to 30MHz MF/HF band (with 88-108MHz broadcast band into the bargain) and offers a wide range of user controls. We thought it apposite to put this review in the same issue so readers can get make their own comparisons . . . 76  Silicon Chip siliconchip.com.au Unusually for a radio of this size, it sports a line-out socket and, more importantly, a fine tuning control to help resolve SSB signals. Having SSB capability brings it right into the amateur radio market – especially at the price. T he first thing that strikes you about the Degen DE1103 Communications Receiver is that it is too small! “How can something this size deliver on the promised performance . . .” As one who was brought up on the b-i-g communications receivers of yesteryear (an ancient Geloso, if I remember correctly!) then through a Heathkit or two and more recently on the ubiquitous FROGs, it does take a bit of getting your mind around the fact that something this size offers performance far and away better than those and features that weren’t even a glint in the designer’s eye. It’s taken the development of microprocessors – as we saw with WinRadio – to get this sort of performance. So how big is it? Try 165 x 105 x 29mm - not much bigger than a typical personal AM/FM receiver. It weighs in at 300g plus batteries. Of course, there have been quite a few synthesised radios around this size in recent years – but this is one of very few (indeed if any!) we can recall which offers SSB (single sideband) reception. What’s so important about SSB? Ask any amateur operator – it puts more “punch power” into the signal by sacrificing parts which can be synthesised at the receiving end. Hence, more range. SSB on a standard AM receiver sounds like “Donald Duck” talk. Back to the Degen. It’s a dual conversion, PLL (phase-locked-loop) synthesised receiver offering continuous coverage from 100kHz through to 29.999MHz, plus the FM radio band of 88-108MHz (in stereo). And while the jog tuning control gives surprisingly good bandspread, you can also directly enter spot frequencies over the entire range. If that’s not good enough for you, there are also 255 memory channels (with memory scanning along with auto band scanning). It is obviously intended for the avid siliconchip.com.au There are sockets for a long wire antenna, headphones and a plug-pack adapator – and all are included in the box. The batteries included are rechargeable (NiMH) types which the external supply automatically charges.‑ shortwave listener as well as a more general market, as the band switch will progressively step it through the popular shortwave radio bands: 75m, 60m, 49m, 41m, 31m, 25m, 22m, 19m, 16m and 13m, along with the FM and AM broadcast bands. Various combinations of pushbuttons also make it perform other tricks, so a good read of the 28-page instruction manual is a must if you want to get maxium performance/ enjoyment from this radio. There’s a couple of controls included “because they could” such as a local/dx switch and a wide/narrow 2nd IF response switch for AM (wide band, <6kHz, has better tone reception than narrow band [<4kHz] but it is also noisier). It has the obligatory digital clock built in (with two alarms, no less) and a 1-99 minute sleep timer. Volume setting uses the same jog dial as the manual tuner and we must confess that is one feature we didn’t like. Perhaps it’s just a matter of getting used to it but we were continually moving off frequency when we meant to change the volume. And speaking of volume, there is plenty! The specs don’t mention the power output but we found that sub-20 (out of a maximum level of 64) was more than enough for normal listening. And as we mentioned earlier, using the jog dial in conjunction with the fine tuning control is more than good enough to resolve SSB signals. We didn’t try to measure sensitivity but deemed it more than adequate. It’s stated as <10uV on FM, <1mV/m on MW AM and <20uV on SW AM. And we didn’t have the opportunity to string the long-wire antenna to see just how much better it could be – but Avcomm’s Garry Cratt told us that he had done so and the performance was even better, as one would expect. OK, so what’s the verdict? We’ve already mentioned the one thing we didn’t like (again, that’s only a preference) but there’s a lot to like about the Degen DE1103. The one thing we haven’t mentioned is the price – and that was a real pleasant surprise. Avcomm are selling this, complete with NiMH batteries, plugpack, longwire antenna and earphones for just $159.00 (inc GST, plus freight). We’re trying to cast our minds back to other receivers in the genre without all the features of the Degen DE1103 and we can’t remember any that even approached this price! For more information call Avcomm on (02) 9939 4377 or visit their website: www.avcomm.com.au SC WHERE can you buy SILICON CHIP You can get your copy of SILICON CHIP every month from your newsagent: in most it’s on sale on the last Wednesday of the month prior to cover date. You can ask your newsagent to reserve your copy for you. If they do not have SILICON CHIP or it has run out, ask them to contact Network Distribution Company in your state. SILICON CHIP is also on sale in all stores . . . again, you can ask the store manager to reserve a copy for you. Or, to be sure that you never miss an issue and save money into the bargain, why not take out a subscription? The annual cost is just $89.50 within Australia or $96 (by airmail) to New Zealand. Subscribers also get further discounts on books, and other products we sell. January 2007  77