OVER 2 YOU, 097 (10/09/02)

VALVE RADIOS

Does anyone know where I might obtain plans to build a ‘valve’ amplifier or radio, and also a source of valves? I remember building one as a young lad and I’m sure I would enjoy reviving the memory.

Peter Knowles, via email

I can recommend a book by ex-BBC sound engineer Morgan Jones entitled ''Valve Amplifiers'', which contains excellent, easy-to-reproduce designs. I have made a pair of 10 Watt units for stereo use and confirm they work well. There is also a magazine, available by subscription only, called ''The Radiophile'', published six times a year by Chas E. Miller and available from the publisher at ''Larkhill'', Newport Road, Woodseaves, STAFFORD, ST20 0NP. Phone/fax 01785 284696. The magazine primarily deals with the restoration of valve radio sets from the 1920's to the end of the valve era in the mid sixties. Another magazine, again subscription only, is ''Radio Bygones'' published by Wimborne Publishing Ltd, 408 Wimborne Road East, Ferndown, Dorset, BH22 9ND. Phone 01202 873872. This magazine is valve orientated but covers a wider spectrum of interest, including articles on transmitters, military sets and companies etc.

Dave Porter (G4OYX)

For valves and amplifier kits try www.maplin.co.uk. I also suggest buying the "Radio and Electronics Cookbook, published by the Radio Society of Great Britain (RSGB), it’s available for £20 from The Modern Book Shop in Praed Street, London.

Rodney Williams

A complete kit of an original 60's amplifier, including the metal chassis already punched to accept the valve bases, the transformers etc. is available from Vyse Ltd., Tel 0208 933 0918 www.torresamps.com.

For data on valves and some prints from the Mullard Circuits Handbook, components etc., try Surrey Amplifier, PO Box 169, West Molesey, Surrey. KT8 2YT or their website www.surreyamps.co.uk
Stan Lawrence

Many years ago I bought a book, which your reader might find useful, titled:"Audio Amplifiers" edited by J R Davies - It was published by "Data Publications of London " and covered designs for "amplifiers for domestic Receivers, Record Players, Tape recorders etc." It was first printed in January 1969 and cost 10 shillings and six pence! Although it almost certainly is out of print, it may be possible to get a copy from a second hand bookshop.

David Cable

Heath Projects (Heathkit) and Dynaco used to supply kits for numerous valve based applications. Luckily somebody has collected them all together and put them on the web at www.circuitarchive.co.uk. As for buying the valves there are dozens of suppliers none of which I am in a position to recommend, do a quick search on Google or go to www.tubecollector.org a site for valve collectors with plenty of links to suppliers in the UK and around the world.
Adrian Sawyer

Peter Knowles will find all the information he requires at the RSGB Bookshop (Radio Society of Great Britain) www.rsgb.org/shop but as far as valves are concerned, production largely ceased about a quarter of a century ago but try www.colomor.demom.co.uk valve holders could be difficult to obtain.

G. Leonard

I am 84 and started winding coils for my fathers friend when I was eight. He taught me about crystal sets then valve radios, I built my first one when I was ten. I became interested in short wave and made what was known as an adaptor to plug into the first valve position, it was housed in a toffee tin to cut down hand capacity. I listened to Tom Mix on W2XAF New York almost every night. When I was twelve I became what may have been the youngest disc jockey. I lived in Liverpool and my 78 records swamped the Seaforth Coastguard radio but I stopped when the BBC Detector van arrived in the street! Great times and I still listen to amateur radio stations all over the world.

John Arnold

I am very much involved with old radios and other valve equipment. There are many dedicated web sites; try www.bvws.org.uk  which is the site of the British Vintage Wireless Society and has links to many others. Also look at www.radio-renaissance.co.uk where you will find links to component & valve suppliers.

Colin Boggis

MODEL DESIGN

Since retiring I have taken up the Internet, model aircraft and model boats. Can anyone recommend a CAD program for general drawings and any specialist design programs for model aircraft and boats.

Dale Broad, via email

We use a very good one at my school called Pro Desktop.  (http://www.ptc.com/products/desktop/index.htm). It is an advanced program allowing you to create your designs in 3D and add different components. If you have the right equipment you can also get CAM (Computer Aided Manufacture) machine to help you build it.

Leo Chancellor

While I have not used this software personally, I believe the best low cost CAD around for what you want is called "Model CAD and Wingmaster’ (www.designcad.com). It was reviewed the August/Sept issue of the US magazine Sailplane and Electric Modeller. To quote from the conclusion
"ModelCAD provides everything a modeller could need in a CAD program.  It has an abundance of features that make creating, modifying and placing items fast and easy.

Robin Sleight

I found a good CAD program (particularly for electronics), which can be downloaded from the Eagle web site (www.cadsoft.de), free of charge, for education and non-profit making activities. I am beginning to get my head around this package now and have used it recently on my personal web site (page 3!) at www.norcim.fsnet.co.uk.

Terry Tippett

I can strongly recommend Intellicad (Try Info@cadopia.com). This has three major advantages: the Intellicad Light program is free, it uses the same DWG file format as the industry standard Autocad and it is very powerful. I have found the suppliers to be extremely helpful. You need to be aware that it is a professional program and therefore will repay time spent learning to use it. There is a professional version, which is not too expensive, which emulates most of Autocad's features. The use of a program, which uses DWG as opposed to DXF format, is a major advantage when interchanging files with bureaux etc.
Michael Bennison

Try Turbocad (www.turbocad.com). It’s easy to use and much cheaper than Autocad. Their 3D Designer package is all that should be needed.
Nick Taylor

OLD CELLPHONES

I have three analogue cell phones, all in reasonably good condition. The networks have long since stopped operating so is there anything I can do with them, apart from waiting fifty years for them to become collector’s items?

William Temple, via email

There is really nothing you can do with them. Their frequencies are being re-allocated to the digital phones, and their operation is controlled by complex software, which needs to be able to communicate with a network.

David Sharp

Sorry, they’re practically worthless and are likely to stay that way for a long time, even the oldest and presumably rarest models only receive bids of a few pounds on auction sites like ebay. If you do end up throwing them away I urge you to be careful when disposing of the rechargeable batteries. These contain toxic chemicals; there should be a bin or receptacle for old batteries at your local cell phone shop, you’ll also find a container at your local council refuse site.

Jenny Calloway, via email

KIRLIAN EFFECT

Does anyone know if the Kirlian effect, whereby using a special camera the ‘aura’ generated by living things can be photographed, can be captured on a digital camera, and if so how?

S. Woodward, via email

The Kirlian effect is achieved by placing an object on a photographic plate and running a voltage through it; the glowing, neon image recorded is, depending on who you ask, either a supernatural 'aura', or merely the result of moisture in the object conducting this electrical field.

Whilst it may be possible for a sufficiently talented engineer to construct a large CCD sensor (the digital equivalent of a film plate), the chances of being able to run a large voltage through it whilst capturing a usable image seem remote. In any case, photographic film would be a lot cheaper.

Ashley Pomeroy

I was amused to read S. Woodward's letter (Over2you, 27th August 2002) concerning his scepticism about the (non-) existence of the Kirlian effect. At the European Patent Office, we have many documents describing how the Kirlian effect may be photographed; some even claim to be able to use the Kirlian effect to diagnose certain illnesses.
Ian Chapple, European Patent Office, Rijswijk, Holland,

CAN YOU HELP

I'm looking for some software that does CGT calculations for multiple sales/purchases of the same shares. It should be a purely mathematical calculation but it can be rather complex - it could even be a spreadsheet application. Any ideas?
Bryan Peak, via email

I wonder if anyone knows of a computer map of Northern Ireland showing the latitude and longitude of railway stations etc. I’m also looking for a web site that lists towns and villages in the UK with their population, it would be helpful to have a search facility for say find all towns/villages above 2,500 people.

Geoff Endacott, via e-mail

I am in the process of collating my record collection onto a database but not having a scanner can't include pictures of the album/CD/tape sleeve/inlay card. Does anyone know of a site where I can download sleeve pictures that I can then import into my database?

Steve Elliot, via email