Degen DE1103

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Degen DE1103

Post by RF-Bot » Tue Apr 24, 2018 10:42 pm

Submitted By: Jason.


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Not so long ago, the tag "Made in China" had all sorts of negative connotations to it in the Western world. Cheap, poorly made, not well designed or finished are all qualities that used to come to mind. Well not any more! Chinese manufacturers are starting to realise they can be a dominant player in world markets, but only if they lift their quality control, yet still keep their prices cheaper than the competition. A Chinese radio manufacturer has been selling quite a variety of AM/FM and shortwave receivers under the Degen and Kaito brand names, and they've been making quite a name for themselves, especially with the DE1103 model.

So what is the DE1103 receiver? It's a portable shortwave receiver covering 100 kHz to 30 MHz in AM & SSB modes, and 76 to 108 MHz in wide-FM (i.e. broadcasting) mode. It has digital PLL tuning, digital frequency display and a simulated analogue 'needle' and scale display, 268 memories, as well as a few other useful features thrown in too. Getting your hands on a DE1103 is not as convenient at making a trip to your local K-mart and picking one up from the display shelves. Mail order from either Av-Comm in Sydney or direct from China are about your only options. I chose to buy from a Chinese eBay supplier with the username 'sunslf', mainly because the price was so good and the promise of a fast delivery at a reasonable rate. For AUD $68 plus $26 postage, I was the happy recipient of a Degen DE1103 direct from China in exactly one week. I've heard equally great experiences from another eBay seller "liypn' too.

You will note the colourful packaging once it arrives, in a much smaller package than expected. Inside the package you see the radio itself is also much smaller than you think: 170mm wide, 107mm tall and 30mm deep (includes protruding knobs). Yet this tiny package packs a real receiving punch as we will soon see. Also included as standard is a set of four 1300mAh NimH rechargeable batteries, an 8 metre long wire antenna attachment, a drawstring carry pouch, some stereo headphones, a charger power pack and a small instruction manual. My eBay seller even included an AC adaptor to change the Chinese charger power pack to suit Australian power points.

Now, even though the supplied NimH batteries are of apparently good quality and will power the radio for a good 20 hours when fully charged, the first thing I did was to replace the batteries with higher capacity 2600 mAh rechargable's. Two weeks later, with many all-night 'forgot to turn it off' listening sessions, its still going strong and the built in battery gauge still has not moved off full. The way Degen has implemented an internal battery charging facility is unique – you specify the charging time in hours (up to 23 hours) for charging. The radio will then charge your batteries for that period of time at a fixed rate of 100mA and then shut off. I like this arrangement for several reasons: if you know your batteries are only half discharged, you can set the charging time accordingly so that they will not be over-charged. Its also a nice simple, fool proof system; chargers that automatically detect when a battery is fully charged do not always work quite as they should, especially when batteries are getting old. Besides, this arrangement is in keeping with Degens philosophy of making the radio as affordable as possible.

As you look at the radio, you can see that there is a 8cm speaker, what looks to be an analogue tuning display, a small horizontally laid out keypad, and some function buttons on the front panel. The left side has the charging input socket, a 3.5mm stereo headphone socket, a Local/DX (attenuator) switch, and a 3.5mm audio style socket used as an external antenna input. The top has a telescopic antenna that extends out to a generous 91cm long – this telescopic antenna is not a robust item, perhaps because its made of reasonably thin metal to keep it compact as possible, so you will need to treat it carefully. On the right side panel there is the tuning knob, a BFO fine tuning knob, a wide/narrow bandwidth selector switch, a backlight on/off switch and a 3.5mm stereo line out socket. Even the back panel has a useful device: a little fold out flap that acts as a stand when sitting on a desktop, and some little rubber feet to stop the DE1103 from sliding about. Overall, the build quality of the Degen is excellent too.

Turned off, the Degen DE1103 (sold as the Kaito KA1103 in the USA) displays the time of day in 24 hour format in the top of the display. If you push the VOL button while turned off, you get a little bar graph showing up how much charge is left in the batteries. When you turn on the DE1103, the clock is replaced by a digital frequency display, and beneath it the analogue 'slide rule' type tuning scale also shows up with a simulated tuning 'needle'. Given the digital frequency display, is this simulated analogue tuning display even necessary? Some people like it, others do think its a waste of space. I've no feelings about it one way or the other myself. The current volume setting is also normally displayed as well. One strange quirk is the digital adjustment of the volume: this is done by pressing the VOL button, then using the tuning knob to set the volume to the desired setting, and waiting for a few seconds for the setting to be accepted. The way in which this operates might not be quite as convenient as a dedicated volume control but it does do away with a failure prone analogue volume 'pot' which can age, become 'scratchy' or stop working completely when dust gets into it. In a portable radio like this, that can be an important consideration. There is no 'squelch' or mute function.

As you tune through the bands using the tuning knob, you will find the Degen tunes in 'blocks' – when you reach the edge of one block of frequencies, it starts tuning at the start of the same block again. To change between 'blocks' you use the band- or band+ buttons. There are some 'gaps' between some of these blocks, to tune these you need to use the 'direct frequency entry' method, which is as simple as typing the frequency in kHz and pressing BAND+ for any shortwave frequency, or typing the frequency in MHz and pressing BAND- for any FM broadcast frequency.

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Once you've found a good frequency to listen to, you might want to save it to one of the 268 memories available. The first 99 memories are designated channels 0 to 99 as you would expect, but rather than continuing on to channel 100, the DE1103 begins to designate the channels in a hexadecimal format. If you do not like the hexadecimal system, then just use the first 99 memories, and consider the remaining 168 memories as bonuses that you do not have to use. In case you were wondering, there is no 'scanning' of any memories like you might find on a scanner. Despite there being no memory scanning feature, there is a frequency searching facility. Many will be happy to hear that there is a signal strength meter – it looks as if it's a 9 segment bar graph, but in reality it is only the equivalent to a four segment meter. Even so, it still works well. It doesn't function at all on the FM band however.

What other creature comforts are there on the DE1103? There is a line out socket, quite unusual for a portable receiver of this size or price bracket. The headphone socket is a standard 3.5mm stereo type, and yes, you do get stereo out on FM broadcasts. The red LED below the SSB button will illuminate during reception of FM stereo broadcasts. The same red LED is lit when SSB reception is selected for shortwave receiving. The backlight switch when turned on will backlight in a soft orange light both the frequency & dial display, and also the keys as well, making night time operation very easy. If you have an external power supply plugged in, the backlight is permanently on when the backlight switch is selected on, otherwise when running on battery power only the backlight will operate for a period of 10 seconds with each key press. Pressing the TIME button will show you the current time-of-day display, and there is also a keylock function to prevent accidental key operation – this can also work in the power off mode to stop the radio from being accidentally turned on. If you find you cannot turn on the Degen, try pressing the HOLD button for a second to disengage the keylock first. There is also a recessed reset button, which will not erase any memories, but will reset the time of day clock, and restore normal operation if something should go wrong and lock up the Degen – not that I've had that happen to me at all. There are also two wake up alarms that will turn the radio on to a programmed memory channel at your nominated time, and a sleep timer to turn the radio off – making the Degen DE1103 an ideal travel companion.

OK, so we have seen the Degen is a nice small radio and has some features that you would definitely not expect to find on a receiver of this size or price previously. But how well does it actually receive signals? This radio has astonishing performance, certainly much more than it has any right to given the price and its diminutive size.

Let's start with the shortwave performance. I think Degen have hit the right mix of high sensitivity and good selectivity. The sensitivity is boosted when using the attached telescopic whip with a FET front end, but this FET is disconnected if you connect an external antenna via the 3.5mm antenna socket; this is a desirable design feature, as a large external antenna could easily overload the high sensitivity front end. And then if you still have potential problems, you could use the attenuator which works very effectively. However, here in Australia and New Zealand, shortwave signals are generally not as strong as other locations and having high sensitivity is a plus. The DE1103 scores well here. You could be forgiven for thinking that all this is too good to be true – there must be a down side. And you would be right too: the Degen has some image problems, despite having an up-conversion scheme to about 55 MHz for the 1st IF stage.

Importantly the DE1103 has a relatively low noise receiver – other receivers of this size are quite noisy and this noise 'inside' the radio can mask weak signals, and make strong signals not as pleasant to listen to as they could be.

To many, the Degen will appeal due to its SSB reception capabilities, opening up the ability to receive many utility type transmissions such as trans-oceanic aircraft, shipping, military and a myriad of other such users. The Degen uses a BFO for SSB reception, and it's dead simple to use. Tune in the frequency, adjust the BFO thumbwheel on the side of the radio for natural sounding resolved audio and you will be set. Listening to 5643 kHz, a favourite aircraft frequency of mine, even after leaving the radio on all night, after waking up in the early hours of the morning I found the tuning to be still spot on needing no adjustment of the BFO. It's a credit to Degen's designers that this radio can quite happily listen to amateur radio transmissions from literally the other side of the earth (to be precise, England and Hawaii) on 14-odd MHz with just its own telescopic whip while leisurely sitting down in the back yard one afternoon. These already weak signals in this part of the world are made even weaker by the current sunspot minima, so the Degen is really acquitting itself very well indeed to be able to hear these on a 90cm long whip. When you do attach a decent HF antenna to the DE1103 via the external antenna jack, the results are just as impressive – little overload, good quality recovered audio, and surprisingly no real problems, which is amazing considering my experiences with other receivers of similar size or cost. An MTA HF receiving antenna works really well with the DE1103, the quiet noise floor of the radio being well suited to the low noise MTA antenna. Using a 3.5 MHz dipole also gave very acceptable results too.

In both AM and SSB modes, the bandwidth selector switch works very well – for SSB you will probably be using the 'narrow' position all the time. This selector switch is not just an audio bandwidth selection either, it selects between two sharp 450kHz ceramic filters. On the MW broadcast band, the DE1103 definitely doesn't disappoint. Its certainly not the most sensitive radio I've ever used in that part of the band (a high quality car radio will hear weaker signals a bit better) but its selectivity certainly makes up for that. Unfortunately the external antenna connector is disconnected and is of no use on the MW and LW bands. Also, image problems from MW stations do show up when receiving LW frequencies.

This only leaves the FM band to cover. FM band reception is astonishing! This is by far the most sensitive FM broadcast band receiver I've ever used – by a long, long way! For example, my first few days with the Degen were spent on remote King Island, to the north-west of Tasmania. Located in the southern half of the island, I was able to receive FM stations from Melbourne some 265km distant, inside a metal-clad cabin, in clean stereo! The next day, making a trip to the northern half of King Island, standing on the beach at nearly sea level, I was able to hear FM radio stations from Mt Wellington in Hobart (438km distant), again in crystal clear stereo! Remembering these results were just using the radio's telescopic whip and nothing else. Amazing! The bandwidth selection for FM acts as a tone selection switch, which does make a weak hissy FM signal easier to listen to. The FM band will tune from 76 to 108 MHz, and I guess some of you will be wondering how it may tune two way radio services in the VHF mid band from 76 to 84 MHz? Well, it will work, sort of... the recovered audio is very soft, the filters are far too wide for NFM work but its better than nothing.

Generally the audio produced by the DE1103 is very good, much better than what you would expect a small radio like this to produce. Ease of use of the radio is not too bad, though that volume adjustment is a bit fiddly and takes some getting used to. But otherwise the radio is well constructed, and taking a peek inside reveals that the quality of soldering and components used are generally good as well.


Like all popular radios, the Degen DE1103 has several modifications available to it. You can:
  • Modify the audio for better response and clearer sound.

  • Modify the telescopic whip input circuit to prevent static damage to the sensitive FET front end – the latest versions already have this installed at the factory.

  • In some older versions of the DE1103, the sensitive FET front end was not disconnected when an external antenna is plugged in, causing potential overload; this can be rectified if necessary.

  • Improvements to the PLL synthesiser to remove the slight 'blip blip' sound when tuning across the bands quickly.

  • Improving the sensitivity between 15 and 30 MHz – may not be required on the latest version of the DE1103.

  • Swapping the BFO fine tune and volume controls around, which some users may find more convenient – I would not recommend this for frequent SSB listeners myself.

  • Changing the AGC time constant, though again I do not see the need for this.

  • Improving the shielding to improve the image rejection, and improve the stability.

  • Increasing the battery charging current for faster charging.

  • And lastly a purely 'soft' modification that is done entirely by key sequences without opening the radio to tune below 100 kHz and above 30 MHz – I've heard that they will tune up to about 36 MHz, but only in AM and SSB mode.

Some of these modifications were aimed at earlier versions of the DE1103 (i.e. the disconnecting the FET preamp when using an external antenna), some are more about personal preference, and some are still applicable to the very latest versions of DE1103s. According to the printing on the PCB, my review Degen is a Version 4. Be warned though, the mods are not easy to carry out; you must be comfortable with soldering tiny SMD components, cutting tiny PCB tracks, metal fabrication and delicate disassembly. Whichever mod you are considering, be very careful. There are some excellent internet resources for modification & technical information, the best one being the "de1103" yahoo group where you can download schematics, block diagrams, modification information, performance specifications and lots of Degen DE1103 enthusiasts.

In all, the DE1103 offers brilliant performance for the price. To coin a phrase some work colleagues used "cheap at twice the price". If you are looking for your first shortwave SSB receiver, a portable travelling radio, or a second HF receiver, the DE1103 is just the ticket.

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