The Oldham Radio Club Rally was held at the Oldham Sports Centre, Lord St. Oldham on Sunday 23^rd January 2005.

It was touch and go as to whether the rally would ever go ahead due to the very late booking of the majority of the traders. The major players had booked in early as anticipated but the remainder did not show any interest until after the New Year was well aired. This gave rally organiser Steve Crane G0KUY plenty of work and headaches in trying to persuade traders to commit themselves to coming or not. In the end though his hard work was rewarded by having an almost fully booked event with 37 exhibitors committed to come.

The hall layout was conceived and completed by Club Treasurer Geoff Ashton M0AUG and Club Secretary Mike Crossley M1CVL who pieced the bits together through the weekend preceding the rally. Mike was then able to produce and print out the rally programmes. He also produced the Club Members Identification Badges.

On the Saturday afternoon of the rally weekend 6 members met at the hall to set out the table layout. Sadly one of these, Bertie Whitcher G7JUL was given a parking ticket for under payment for the length of his stay for this afternoon session.

Before the Sunday dawned members gathered at the hall to meet the first trader. As usual this was Waters and Stanton who actually arrived slightly before many members but their vehicle was swiftly unloaded and their goods moved to their tables. Incidentally Mark Francis from W&S especially asked that club members receive his thanks for the help and assistance given to him on the day. Slowly but surely all the other traders and exhibitors arrived and were unloaded. In fact this process went so smoothly that we were able to open the rally early at 10:15 as a queue had already formed at the entrance.

Talk-in was hosted by Geoff Oliver G0BJR and Keith Feay G1GZK from our club shack and throughout the day helped around 40 people to find the venue.

For the first time this year we were honoured to have the President of the RSGB Jeff Smith MI0AEX as our guest. He spent the whole day meeting people and having a good natter. He even helped out with clearing away at the end of the event. Our Chairman gave him an official welcome after he had shut down the talk-in station. (see photograph which was taken by Jeff Hollowood G7LMI). We received word later that he had really enjoyed the day.

Once again, and as we have come to expect over the years, members pulled out all the stops to help out at both ends of the day. Goods were moved from vehicles to tables and back again with speed, efficiency and good humour. Members efforts were also required through the day for door takings, and many other organisational tasks. All vital in their own way in contributing towards the overall success of the event, not only for our club but for the traders, our visitors and guests.

Our friends from RADARS, the Rochdale and District Amateur Radio Society, organised and ran the Bring and Buy for which they receive our thanks and hopes that they had a good day.

The club’s web site at www.oarc.org.uk scored many hits in the weeks preceding the event. During the last 2 weeks some 300 hits were counted but another 400 were counted in the final 24 hours before the event. It is now quite obvious that this plays a significant role in attracting visitors to our event and the efforts of Geoff Ashton M0AUG and Mike Crossley M1CVL to produce rally documentation for posting on the site are well worth it.

Finally thanks go to all members who helped out to make the event possible. It was by no means certain that the event would take place as traders were so slow to respond to our invitations that there was a strong possibility that it would have to be cancelled. In the end it all happened and this is mainly due to the dogged determination and persistence of Steve Crane G0KUY. Well Done Steve and many thanks. You can rest now until September when it all starts again.

Photographs of the event were taken and provided by Jeff Hollowood G7LMI, Jack Elliot G3KIQ, Craig Taylor G7MCT
and Becci Davenport 2E1INC.

Old Hams News has taken on a slightly new look. Because of the new method of distribution I can be much more adventurous, imaginative and flexible in the production of our tome.

Apart from making a considerable financial saving for the club the technical quality of the document can be enormously improved. More photographs can be imported and they can be displayed in colour and higher resolution. The weak link in the chain of production previously was always the final photocopy run. A superb example of this is the photograph of the overview of the Sports Hall in the Rally Report. It would have been impossible to use this great picture in the photocopied version because in the final print it would have been reduced to an indistinct muddy mess.

The front page has also been reconstructed. This has been done mainly so that the whole document can be compressed into one file instead of two. Previously the front page was created using a desk top publishing program which produced a large file size. Now the page is created in the word processing program as an integral part of the overall document. Thus making just one file instead of two and reducing the file size at the same time.

You also have the choice to either print out your own copy of the document or to read it directly off your monitor screen. Coming as it does as a pdf file it is easier to store than a paper copy and if you are concerned about environmental issues this is a much friendlier way to keep your copies.

It is possible that some of you may dislike this method of distribution, and if you do then I commiserate with you but this is the way your committee has decided to go in making financial savings for the club. Declining income from the rally and maybe its complete demise in the future would make it impossible to produce Old Hams News using the previous method.

If you have any "constructive" comments or suggestions on layout or content of our journal then please contact me and I will be delighted to consider them.

Geoff Oliver G0BJR
Chairman and Editor

DAB vs WS vs FM

An interesting heading? We’ll see – read on.

Just over 2 years ago I purchased a WorldSpace Receiver and composed a report on it in the January 2003 edition of OHN. Later another report appeared on the topic of Digital Audio Broadcasting. This dealt more with the technical quality of the DAB transmissions rather than the choice of stations. Now this following report is an update of sorts and a comparison, both of technical quality and of programme choice.

WorldSpace has proved to be a waste of space as feared in my earlier column. However because of the choice of receiver purchased it is not a complete loss because the radio is also an excellent VHF/MW/SW receiver and is in daily use on these bands. WorldSpace is currently transmitting 35 radio stations from the Afristar Satellite. Not bad you might think. But of those 35 stations only 8 are transmitted "in the clear", all the rest are encoded and a subscription of $10/month is required to open the others up. Sadly amongst those now requiring a subscription are, Maestro - a very listenable Classical Music Station, The Hop – also very listenable 50’s, 60’s and 70’s music station, and Riff – a modern jazz music station, and these were the stations I listened to on a regular basis.

The subscription issue is hardly surprising as I never heard any advertising on any of these channels and I suppose the service has to be funded somehow. However a subscription based radio service will always be a non starter in this country as we have been spoilt by superb radio output from both the BBC and Independent sources at no charge. Also the transmissions emanate from a satellite primarily aimed at the African Continent. This is an ideal method of bringing radio to a massive area and to a potential massive audience. But the majority of that audience probably does not have enough money to purchase the batteries for a WorldSpace receiver, so it is most unlikely that they will pay a monthly subscription. This makes the decision to impose a subscription charge for this region somewhat mysterious to me.

So having largely dumped WorldSpace I reverted back to the previously mentioned superb and free transmissions from the BBC et al. But as the VHF tuner in my Hi Fi system was growing rather long in the tooth and showing signs of its age – some 25 years plus, I decided it was time to replace it. And now that Digital Audio Broadcasting is becoming more popular and there is now a good choice of portable and fixed models available at affordable prices I opted for a DAB/FM/AM tuner to see how that went.

After connecting the beast into the Hi Fi system and sticking the supplied wire dipole antenna to the wall with Blue Tack (much to my XYL’s annoyance) I switched on and pressed the autotune button. It scanned around for a while with various letters and numbers flitting across the display panel which eventually stopped and boldly stated "No Stations Found". After repositioning my jaw and the antenna I manfully poked the autotune button once again. This time after the same whirling of letters and numbers the display informed me that it had found one station – BBC Radio 1, a station I will never knowingly select. Time for a rethink, I think.

While the rethink was going on I selected the FM band and did an autotune and low and behold a plethora of stations were being listed on the scrolling display. Mind you I have a dedicated FM radio antenna mounted on the chimney so this was not surprising. It was pleasing to see that the RDS function was working so beautifully that it even gave scrolling programme information in addition to the station identification. Something I did not realise was even transmitted in this band. BBC GMR is particularly good in this respect.

Flushed with success I quickly tried the AM facility, which again worked perfectly even though the antenna was pretty makeshift.

So back to the DAB band. I moved the antenna as high up the wall as it would go and this time did a forced autotune. The results were startlingly better. This time the display informed me that it had found 17 stations so I started going through them. Some were quite good quality but the reception quality of many others was so bad that it just sounded like severe flatulence in the bath. It was quite obvious that my antenna was totally inadequate and I would have to do something else.

One of the contributing problems with DAB reception in our geographical location is the power of the transmissions. There are 2 frequency bands allocated, Band III, which is approx 220–230MHz, and ‘L’ band which is approx 1.4GHz. There are 2 transmitter sites. The main, or National Multiplex is at Winter Hill emitting at 10 Watts, - that is not a misprint, TEN watts. The other is known as a local multiplex located on the Sunley building at Piccadilly Plaza in city centre Manchester, which emits its RF at 0.5 Watts, yes half a Watt. No wonder I was struggling. The normal FM transmitter at Holme Moss whacks out 500KW – a massive difference.

The following weekend I was able to produce a makeshift antenna and mount it in the loft. I then forced the autotune once again. Instead of the usual skittering of data on the display, this time was a solid message with a progress indicator and a count of stations detected. On completion it proudly stated that it had now stored 37 stations. They can be seen below.

I eagerly started selecting them. The display gave a signal quality reading of between 95 and 100 depending on the station tuned in and all were perfectly resolved with no bubbling. I admit that my knowledge of the technical aspects of the transmission techniques of DAB is sadly lacking but I can judge the technical quality of the transmission with my ears, and the audio quality of those stations I could receive with the original antenna (those that weren’t bubbling) had dramatically improved. But referring back to the previous article on DAB in OHN, is the audio quality as good as or better/worse than a good FM signal? And how does it compare to a CD?

The defining factor in the quality of a DAB transmission is the "streaming bit rate". Apparently the data is sent in a stream of bits. The more bits sent in one second increases the audio quality. So a broadcaster has to estimate what an adequate bit rate is for the type of programme material he is transmitting. A speech only station only needs a low rate where a music station needs a much higher rate. For example BBC Radio 7 which broadcasts repeats of comedy programmes like The Goon Show, Round the Horne and the Navy Lark only needs a low bit rate to achieve an intelligible quality. But BBC Radio 3 broadcasts Classical music, where a much higher bit rate is necessary. The balance between quality and cost is very fine indeed. The higher the bit rate, the higher the cost and a reduction in the number of stations that can be transmitted from a multiplex.

By tuning in the same station (BBC Radio 3) on DAB and FM and making a rapid switch from DAB to FM the FM station was slightly better. It seemed to be crisper. Doing the same test with Classic FM there was a slightly more noticeable improvement on FM. Although it may not be a fair test using Classic FM because they seem to use massive audio compression so that all the quiet passages of music appear from your receiver at the same volume as the loud bits. This makes it very easy to listen to their broadcasts in a noisy environment such as a car or a kitchen. BBC Radio 3 uses less compression of their audio and even then only for drive time programming. One very noticeable difference though is stereo separation. This is much better on DAB than FM.

And what about a CD? No comparison. The CD wins hands down.

Where DAB really wins is with BBC 5 Live. The audio quality here is massively better than the MW broadcasts. Another huge advantage is the extremely efficient use of the frequency spectrum. The table clearly shows the number of stations transmitting on the same frequency.

One extra feature that DAB offers is a scrolling information display of the track that is playing and the next track to be featured. But BBC GMR uses this facility to give weather forecasts, traffic information and news headlines.

There are many stations appearing now on DAB that are exclusive to the medium. Sadly, the majority of broadcasters seem to think that the listening public only wants to hear Pop and Rock Music. When you have heard one, you’ve heard the lot, because they all sound the same. Standing out from the crowd are BBC R3, Classic FM, BBC R5, DNN, BBC R7, Oneword, Talksport, and Primetime which are unique in doing something else.

Interestingly BBC World, Virgin and Talksport that are free and receivable on both DAB and MW have to be paid for from WorldSpace. Work that one out.

If you have Freeview or Digital Satellite receivers many of the stations listed in the table can be heard via that medium.

By Geoff Oliver G0BJR

Up until late January we thought that we would not be taking part in Thinking Day on the Air this year. During December 2004 a message had been received from Margaret Kenworthy, District Commissioner for the Royton Guides and Brownies, to the effect that because of the number of girls that had attended the event in 2004 and gained their Radio Communications Badges, there were not enough new girls to make the event viable in 2005.

However, the Guide group from St. Anne’s Church in Lydgate who had never attended a TDOTA event heard that we were not putting on the event for Royton Guides requested that we put on the event for them and other Saddleworth Guides and Brownies. We agreed and after receiving the licence and callsign GB2OSA (Oldham St. Anne’s) arrived at St. Anne’s Parish Church hall on the morning of the 20^th February to set up and take part in the event once again.

The day began at 07:30 when I began loading the car with all the equipment necessary to put on the event. On arrival at 10:05 and looking around the grounds it soon became apparent that this was going to be a challenge and not an easy thing. The front of the building was on a main road and the south side of the building had a public footpath running along the side with houses next to that. At the rear of the building was a playground and was lovely apart from the fact that it had a tarmac surface. Beyond the playground lay what can only be described as a builders yard as the pub next door was having an extension built onto it. This put the option of putting an antenna in the pubs grounds out of the question. The north side of the building was also a small tarmac playground. To make things more complicated all around the building at about 12 ft above the ground were power cables or telephone cables.

After going inside and asking where we were to set up the station it seemed that they were asking the impossible. The stage is where they wanted us to go. If this option had been taken there would have been no windows to put the coax through and a feeder run of nearly 50 metres for both HF and VHF would have been necessary. HF could have been operated with this kind of length but most certainly VHF would have been dead. I quickly told them that in order for us to operate we must have a window access in order to get the coax into the building in as short as run as possible.

The main hall was being used until 13:30 by the church tea group. This meant that a side room had to be cleared to make room for an HF shack and the small hall would be used for VHF. The inside was decided and that was that. Outside still had its own headaches, lots of cables already in the sky. With a half size G5 it would not have been a problem. But this was not an option; we wanted a full size positioned as high as possible. The only place for this was along the side of the building where the footpath was. At the top end there was a telegraph pole that most of the cables ran from. A rope was placed around one of the top foot pegs and the G5 attached. Running it down the side of the building it was clear that we would only just make it to the front. We erected a 30 foot mast at the front with the colinear atop it. The G5 was placed over the top of the mast using a pulley to allow us to tension it. Luckily my car was parked at the front and this allowed us to tie the tensioning rope to the roof rack. This stopped the mast from bending because with the playground being tarmaced there was nowhere to put any anchor points for the guy ropes. This was a problem around the whole building.

While we had been putting up the antenna system others were inside setting up the Yaesu FT990 and FT847 transceivers. All that remained was to connect them together and see if they worked. On test both stations worked well and there was time to spare. It was 11:15 and as we were scheduled to start operating at 12:00 the guide leaders set out the refreshments, sandwiches, cake and fruit, and lots of tea and coffee which was enjoyed by all members. It was nice to relax and prepare for the arrival of the girls.

The first girls arrived and the serious stuff began. Being at 1000ft ASL makes a big difference. HF was busy and it was difficult to find a clear frequency. This was a nice change from not having enough stations to work. Club members took turns in operating the stations and putting girls on the air but the bulk of the operating tasks were borne by Alan Burgess G4GLV with Sue Burgess G0RKE on HF and Elizabeth Crossley M0LIS with Mike Crossley M1CVL on VHF. Of the stations worked an interesting one was a TDOTA station located near Rotterdam, Holland with the callsign PH2TD who had lots of girls attending all of whom spoke remarkably good English and was happy to work lots of GB stations. Other TDOTA stations worked included stations in Montrose, Wales, Lincoln and Astley.

VHF went quiet in the mid afternoon and unfortunately one or two members had to resort to working their handhelds from outside which was a job and a half because of the bitter wind. Thankfully the snow had not arrived as was predicted by the weathermen.

Unfortunately the turn out of Guides was disappointing. Although the majority of the St. Anne’s Guides attended the other groups had declined at the last minute. This meant that the 25 girls who did attend could have several turns on the mike and they took full advantage of the opportunity. It also meant that the event finished earlier than planned. The station was dismantled at 14:30 and by 15:00 everyone was on their way home.

We would like to thank the Guide Leader Sue Lumley and her colleagues for their hospitality in providing us with the opportunity to take part in the event once again, and for the copious refreshments they provided for us.

Many thanks also for the help and expertise of the following members,

Photographs by Geoff Oliver G0BJR and Chris Mackay 2E1MDC

By Chris Cunliffe G7OOD