Monday, 20 December 2010

DAB Radio

Just to make a change from Amateur Radio topics, this post is about domestic digital, DAB Radio.

Those of you listening to the BBC, in UK, can hardly have missed the adverts encouraging us all to rush out and buy a DAB radio for Christmas. There is of course a hidden agenda - the Government is just itching to grab back the FM broadcast band so it can sell it off. The have set a threshold of 50% of all households owning a DAB radio so they can name a date when FM transmissions can cease - even this very low criterion has not been met yet. These are my thoughts:
  • The UK Government have chosen the wrong system for DAB. They should have chosen the newer DAB Plus, which is used elsewhere in Europe. DAB and DAB Plus are not compatible so if they try to adopt DAB Plus, then all existing radios will be useless.
  • In my experience, DAB offers no better quality than FM, provided the signal strength is good.
  • DAB radios eat batteries so realistically have to be run from a mains power supply (My Sony XDR-S55 DAB radio is particularly bad, it runs off AA batteries and draws 200mA, which means about a 6-hour battery life. To make matters worse, this radio has an FM band but it continues to draw 200 mA even when switched to FM).
  • Most of the country, by area, either cannot receive any DAB signal or can only get a few stations. So it is not clear to me how DAB can be viable for car radios or those who live in remote areas. I did not find much evidence of a plan to improve this coverage rapidly.
  • Your DAB radio will not work abroad, apart from in a very few countries that use the UK system.

I do not want to be totally negative about DAB - there are some positives. If you live in a good signal area then you will get a lot more stations. Whether they are worth listening to is a matter for you! Some radios also give a text display, giving limited information about the programme you are listening to.

So should you ask Santa for a DAB radio in your stocking? If you are sure you live in a good signal area, you want the extra stations and you don't mind running the radio from the mains, then go ahead. BUT - do make sure your retailer will give you a refund if your radio does not receive the stations you expect - the coverage maps can sometimes be optimistic. You also need to be prepared for DAB to be phased out in favour of DAB Plus. This is not likely, in the short term, but you will almost certainly need to invest in a new radio if this happens.

I do not have any experience of DAB car radios, but I would be quite sceptical about their performance if you ever travel far from the large urban centres. Please post a reply if you use DAB in your car.

Monday, 13 December 2010

2m Club Championship December

For those not famililar with this two metre RSGB contest, it is run on the first Tuesday of each month. Points are per km for each QSO and multipliers are grid squares. Patricipants can add their scores to their club's total. The totals run from January to December for both individuals and clubs.

I have been working overseas a lot this year, but did get on for the December 2010 session. Conditions were quite flat, but as there were lots of stations participating I managed a reasonable claimed score of 11,000 +. I was pleased to work a station, M0GMG/A in IO83 - some 230 km away, which is not bad for 25 Watts and a 5-element beam in my loft.


Friday, 26 November 2010

This is me reading the Wouxun handbook:

and out and about with the supplied (short) antenna
and the optional 'long' centre loaded antenna supplied by Garex (

Monday, 22 November 2010

Wouxun KG-699E 4m Hand-Held Radio

I recently invested in a new Wouxun KG-699E 4m hand-held. The first thing to say is that this is a really good little radio and outstanding value at around £90. The radio has many functions which we seldom need for amateur radio use, though some may be helpful for activities such as Raynet etc. As 4m does not have repeaters, even fewer of the Wouxun facilities are needed on this band.

The radio is small, light but rugged construction. It has a nicely rounded profile the makes it comfortable to hold even for long periods. It Controls are nicely positioned and easy to use. The display letters are large enough to read easily with or without the backlight on. Additionally voice prompts are available in English or Chinese (handy for those of you brushing up your Mandarin). Changing the voice prompt language does not affect the display language, which is fortunate otherwise you would have to learn Chinese script to change it back.

The marketing material is not clear on what bands this radio covers, so let me clear that up. It transmits on 66 to 88 MHz, so, as it is possible to transmit outside the amateur band care is needed. It also receives on the FM broadcast band, which I find a useful feature. As far as I can tell, it does not receive on other bands, but please correct me if I am wrong.

As with most hand-held radios, the Wouxun is a bit fiddly to programme, but optional software and a cable is available and programming it with a computer makes life much easier.

The Wouxun comes with:

A small rubber-duck antenna
One battery
Battery charger
And of course the radio itself.

The rubber duck antenna has been criticized in the press, but to be fair, it is only 1/20 wavelength long so, with that length, it’s never going to be efficient (like trying to work on 20m with a 1m long antenna). However, I have had some good local contacts with just that and its size makes it very convenient when out portable with the radio.

The antenna connector is unusual as it is a male SMA, but I had no difficulty finding adaptors to BNC, N etc. on eBay.

The standard battery charger will either accept just a battery or the radio with the battery in place. The charger can be powered from the mains or from 12V dc, which is useful for portable or Raynet operations. The battery is Lithium-ion 1300 mAh which gives a good operating time and recharges in about 4 hours. The radio does not have an external power socket and as this type of battery ‘falls off the cliff’ when it is exhausted, a spare battery is essential. Batteries are easy to change, but held securely in place with two catches, one on either side of the radio.

The handbook really does need improvement. I suspect it was badly written in Chinese and then translated into English by a non-specialist. Fortunately, however the radio is quite intuitive so the handbook shortcomings are not a serious matter.

On the air, I have had excellent reports. I usually use it with a vertical dipole that I built in my loft from some scrap copper. Unfortunately I bought the radio after the ‘E’ season finished, so I have not worked any real DX, but stations up to 50km are easily workable. The audio reports are good, but on narrow FM I have been told my audio is a bit quiet and there is no adjustment that I can find for this. The receive audio is also excellent quality for a radio of this size.

All round, the Wouxun KG-699E is a great little radio and although it does have a few shortcomings, I really enjoy using it and I believe it will give the other amateur radio suppliers something to think about. The lack of an external power socket has not caused me any problems so far as the battery life is good and they re-charge in a few hours. Their documentation needs to be greatly improved. I have used lots of handheld radios so this was not a problem for me, but could be discouraging for someone who is new to amateur radio.

I really hope Wouxun are successful in this market and bring out a larger range of amateur radio equipment in the future.

Wednesday, 13 October 2010

70 cm Activity Contest

I did the 70 cm activity contest from home last night. I do much better on this band if I can get out portable, but the XYL was using the car.

Conditions had been good over the weekend and I expected great things tonight. Sadly, conditions were very flat here in SE London but, going by the 'Claimed Scores' page on the RSGB web site, stations further north seemed to enjoy good openings.

Friday, 1 October 2010

Wouxun KG-699E 4m Hand Held

I had my first 4m QSO this evening, on the Wouxun KG-699E, with Guy G0UKN, who lives about 6km from me. With the supplied antenna I was 5-8 to him, but with the longer Garex centre-loaded whip ( ) Guy gave me 5-9+, so at least a 6dB improvement.

Guy said the audio was a bit thin, but this improved when I switched to 'wide' mode. Unfortunately there is no mic gain menu on the 699E (or if there is, I haven't found it).
I will write a longer review of the Wouxun, when I know it a bit better, but for now:

"六九九" 是 很 好 !


Wednesday, 29 September 2010

Wouxun KG-699E 4m (70 MHz) Hand-Held Radio

Not only am I back in amateur radio, but I am spending my money as well; I bought a Wouxun KG-699E today. First impressions are good.

Reviews say the antenna supplied with the KG-699E is rubbish so I bought a high-gain whip (£20) as well.

Further posts will follow, but comments on this radio ( and its 2m/70cm cousin the KG-UVPD1P) are welcome here.

CQ WW RTTY Contest

I have been away from serious amateur radio for some time, due to work commitments, but last weekend I had a bit of spare time so had a go at CQWW RTTY. Conditions were awful with the SFI in the low 80s and A-index around 13.

I only operated for a few hours on and off. Made one contact on 10m (Thanks, LZ9W) and split the rest of my time between 40m, 20m and 15m depending on the time of day. Most of my contacts were in Europe with only one state-side (grateful thanks to W4PK in Virginia for his patience in pulling me out of the noise).

I do not like the CQWW contests. The exchange is meaningless - everyone knew I was sending "599-14". Even though I am a very low power station and conditions were poor, only one station asked me to repeat my report. This is not credible. I would also question why only RTTY is allowed. This is an out-of-date mode that eats bandwidth - why not encourage PSK-31 /PSK-63 in this contest?

Comments welcome!