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The Spark That Chan While its origins were in the 19th century, it is widely recognized that radio – and in particular broadcast radio – was one of the most significant developments of the 20th century. by Kevin Poulter T he spark-gap transmitters which came into vogue after the turn of the century were capable of bridging continents but were limited to telegraphy only – Morse code. They spawned a lot of interest amongst experimenters and wireless enthusiasts but as a consumer item, they were a lame duck. It took a lot more development to be able to transmit (and receive) voice and music. But over the next two decades such development did occur and radio broadcasting, as we know it today, became a reality. The equipment to receive those broadcasts naturally followed. Thanks to some inspired and creative inventors and producers from the early 1920s onwards, we can now look back and see radios that are absolute works of art. The wiring is superb and the cases lovingly constructed to showcase the finest possession in the home. Many of these treasures should be in museums but due to a lack of space and resources, plus the overwhelming demand for diversity in their collections, few radios are restored and displayed in public. Fortunately, 25 years ago a group of radio enthusiasts created an organisation dedicated to saving and restoring many of these iconic centrepieces of the 20th century way of life. Now many collectors’ homes display jaw-dropping collections of radio equipment and ephemera (posters, plans, circuits, advertisements and photographs). The HRSA (or Historical Radio Society of AusIn the 1920s, ‘coffin’ radios were connected to external horn speakers like this Amplion. The first car audio systems even had horn speakers. 58  Silicon Chip tralia), was established by a small group of radio enthusiasts, motivated by Ray Kelly, in April 1982. Today, the HRSA has about 1000 members throughout Australia, with a number in overseas countries as well. Not just domestic radios . . . Australian mantel radios are the common interest, however the HRSA includes collectors of all types of receivers and even military radio equipment, television receivers, radiograms and more recently transistor radios. The most advanced members have 400 to 1,000 radios in their collections, so much of Australia’s radio heritage is preserved. What inspires people to share their love of radio and related information? It is the history, electronics innovation, development and amazing quality of workmanship in older radios. One of the greatest motivations is the thrill of finding and restoring a decrepit radio, or even rescuing one from the all too common imminent final journey to the tip and bringing it to as new condition. Stories that chill the blood of collectors abound, like a huge collection of 78 RPM records in fine condition, offered to potential collectors but as the owner was too far away, there was no response. So the whole lot were burnt in a bonfire. Another company, not so long ago, had too many valves, so a skip was hired, filled with these hard-to-get parts and sent to the tip. Most collectors especially like to have at least one nostalgic example of the radio make and model that bought the world to their kitchens or lounge-rooms throughout their childhood. The development, enjoyment and subsequent collectsiliconchip.com.au nged the World ing of radios, had its origins with the music-box – the first mechanical device that reproduced tunes at will. We are familiar with the ‘barrel’ cylinder music-box, however there were also disc versions. Some had different discs or cylinders with a choice of tunes, either fixed in the music-box, or removable, like CD players. With this conceptual background, Edison made a monumental leap forward. He recorded sound onto materials such as wax, then reversed the process to replay it. From this earliest reproduction of sound via a needle there is a direct evolution to the sound, vision and computer discs we enjoy today. Edison made two more vital discoveries in radio’s early history: the carbon microphone and the diode valve. The difficulty with the diode was that he couldn’t think of an immediate application, so it was left to others to develop many years later. The first radio “broadcasts” Once the first sparks were sent through the air as Morse Code (which, incidentally, occurred in Italy in 1895), radio had begun. A host of inventors including Marconi made valuable contributions, until the public broadcasting of voice and music around 1920. Most radio broadcasts of the day were ad-hoc affairs by amateur operators using their own “home brew” gear. There were no such things as schedules or programming! Part of the reason was that there was virtually no receiving equipment, at least not in the hands of the general public. The first public radio broadcasting station is usually credited to Dutch amateur Hanzo Idzarda, who commenced transmissions from his station PCGG in 25 YEARS HRSA The Hague on 6 November, 1919. The BBC started regular broadcasts on station 2MT from London on 14 November, 1922 (even though it had been transmitting for some months before) and Australia joined the radio revolution when radio station 2SB began public broadcasting on 23 November 1923. 2SB, owned by Broadcasters (Sydney) Ltd, had been in a race with rivals Farmer and Company, who promised in August 1923 to start broadcasting from their station, 2FC, on November 15. 2FC didn’t make their deadline and started on December 5th. (2SB later became 2BL and both 2FC and 2BL were later absorbed into the Australian Broadcasting Commission, or ABC). Some suggest 2SB wasn’t the first station to “broadcast” in Australia. It was the first to “officially” broadcast regular programming but the honour of first in Australia belongs to renowned radio pioneer, Charles Dansie Maclurcan, whose station 2CM in Agnes St, Strathfield started in 1921 with a 90-minute concert every Sunday night. Maclurcan in fact had the first licence to broadcast in Australia. And if you’re looking for a question to stump even the most ardent trivia buffs, the first piece of music “officially” broadcast in Australia (on 2SB) was “The Swan” (Le Cygne), from Saint Saens’ “Carnival of the Animals” (Carnaval des Animaux). Do it yourself! Soon private and commercial constructors were making superb valve radio receivers The first bakelite radio, the AWA Radiola C87, the pride of the AWA fleet, is one of the most sought-after radios amongst Australian collectors. Bakelite radios are sometimes discovered damaged, though most not as severely as this. HRSA member Ray Hosking restored this AWA C87 to like new. siliconchip.com.au March 2007  59 and crystal sets, aided by a host of magazines on the subject. Reception was regenerative or superheterodyne (superhet). True crystal sets, now highly sought after by collectors, were built into wooden bases or ornate boxes. My grandfather built a crystal set with twin headphones, so he and his wife could both listen to radio in bed at night. The valve receivers in the 1920s were in ‘bread-box’ shape, with a lid for access to the electronics and valve replacement. Collectors irreverently nickname radios of this era ‘coffin radios’, due to their outline. Wood was the most common cabinet material, though a few were in metal, with the brand embossed on the case or added as an embossed metal plaque. By 1930, two new styles appeared, ‘Cathedral’ and ‘Console’. The Cathedral mantel and table radios had a curved peak, reminiscent of Gothic-style archways and windows, finished in wood or B akelite while the Console was a bigsound, floor-standing, waist-height radio. The Console benefited from its spaciousness, with room for a large speaker and the huge case acting as a superior baffle. The Console’s sound was big, with rich tones. Both types became immensely popular as manufacturers competed for the finest decorative furniture appearance, at The Astor Mickey mantel radio was the first Bakelite Mickey, with the name ‘Mickey Mouse’ on the front. After losing a trademark infringement battle with Disney, the next model was licenced and had a Mickey on the dial and in a colour transfer on the rear. (Below left): once Astor could legally use the name and image of Mickey Mouse, the character featured prominently on their radio and advertising, such as in this advertisement from the December 1933 edition of Wireless Weekly. an affordable price. Householders took great pride in displaying them as the feature of their homes. In the early 30s, a plastic-like material called Bakelite revolutionised the mass-production of radios (and indeed many other products, diverse as wall power/light switches, pens and even women’s jewellery such as bangles). Produced under immense pressure, Bakelite could be manufactured into cases with thousands of identical shapes, with many different colours. It was very durable and simply wiped clean. Australia’s first Bakelite set, the C87 made by Amalgamated Wireless of Australia (AWA), was made in 1932. Soon manufacturers found they could add flecks or veins of colour, resembling marble, making radios that are now highly sought-after. And radio electronics progressed beyond regenerative receivers to top-performing superhet designs. Mains power was not supplied in many towns and farms, so battery sets were very common. People in the bush demanded high performance so they could hear distant stations clearly, so Australian radios compared well with the best in the world. During the Cathedral era in the 1930s, Astor radio introduced the Mickey Mouse radio, a small mantel with big radio performance. Disney objected to the use of his character’s name and Astor chairman Sir Arthur Warner fought his request for a small royalty through the courts, until Disney won. Once Astor was obliged to pay royalties, they took full advantage of the rights and produced a revised Mickey Mouse radio, with a cartoon Mickey on the front and the rear and in advertising. This radio had a very long product life, with a version still being sold in 1943. 60  Silicon Chip siliconchip.com.au Older radios should not be turned on, ‘to see if they work’, as capacitors and other components short or open circuit with age. These capacitors have obvious leakage. Restorers replace capacitors with modern types. To show future generations how the original radio looked, the chassis is photographed before repairs. The replaced capacitors are then stored in a plastic bag near the radio. The ultimate restoration involves cleaning out the inside of the original capacitor, leaving a hollow exterior shell. A 21st century capacitor is placed inside and when re-installed in the radio, it’s impossible to tell from the original. When Astor decided to drop the Mickey Mouse drawings and not pay royalties, a new plastic-cased radio was still cheekily called ‘Astor Mickey’. Both Astor Mickey radio series had longevity, selling for about a decade. Imagine the tooling and production savings. Today an electronic product’s sales life can be less than a year. Certainly this is true of car audio manufacturers who produce one or two model range updates every 12 to 18 months. AWA, led by Sir Ernest Fisk, designed technologically advanced radios. The AWA C87 bakelite set, previously mentioned, is now one of the most sought-after and valuable radios in collections today. By the mid-thirties, AWA designed a large mantel radio said by some to be modelled after the AWA building headquarters in Sydney. Due to the skyscraper like appearance, the radio has the moniker ‘Empire State’, after the famous classic American skyscraper. The style remained in a number of different variations for many years. The small Bakelite mantel radio became the most affordable and purchased radio in the 1940s, with most moving from the big radio in the lounge room to a more compact unit in the kitchen. After all, the kitchen is where most people had the time to listen. from much later times – in the 1950s – so take care. Other hazards include old rubber-covered wiring, either under the chassis or in the mains cord. Unfortunately, the rubber perishes over the years, often leaving bare copper wire exposed. As a matter of course, old mains cords should be replaced. If you want to maintain at least a look of authenticity, woven-cloth-covered mains cable (as used for electric irons) is a reasonable substitute. HRSA members use an authentic-looking brown cotton-covered cable. There are other electrical safety considerations too, perhaps not directly associated with the radio but with the home it lives in! Some pre-50s homes, for example, have power points with Active/Neutral transposition, as they were wired before modern electrical rules. This means you can turn the mains switch off at the wall and the radio will go off. But live (Active) wires still go to the radio. Touching this exposed Active and the chassis or other earth, will be a shocking experience! Using a cheap neon screwdriver, the author found two out of four power points in one 1950s schoolroom dangerously reverse-polarity! So it’s vital to check your power points. In addition, the use of an earth leakage lead or socket (RCD) is highly advised. Regardless, the plug should be removed from the wall before attempting repairs, just in case. Another killer – literally – can be those old-style “mir- Danger, Will Robinson, Danger! While some early battery-operated radios are still occasionally discovered, nearly all collectable radios these days are mains-operated. And they are obviously old, so the HRSA promotes safety as paramount. For example, in some models of the Empire State radio, heat-insulating material was placed between a valve and IF (intermediate frequency) transformer, to avoid the transformer drifting off tuning as the radio heats up. The insulating material? Asbestos! Don’t blame the manufacturer – in its day, asbestos was considered a wonder insulator and nobody knew of any harmful effects. Today we know that you should not break up or even touch this material without protection. Some authorities even maintain the slightest inhalation is highly dangerous. Despite this, left alone, asbestos poses little health risk, so most states still allow sales of collectable appliances with this material. Incidentally, we have also seen asbestos in radiograms siliconchip.com.au HRSA member and 32V “fanatic” Greg Lamey adjusts a 32V vibrator in his radio shed at Cuddlee Creek in the Adelaide hills. Near the shed is a 32V wind-powered generator restored with parts scoured from the Nullabor Plain and other remote parts of South Australia. It supplies a large bank of ex-telephone exchange batteries with two 1930 Ruston-Hornsby diesels for backup. March 2007  61 It’s not all valves and high voltages : early model transistor radios – such as this AWA Radiola Transistor Seven – are also lovingly restored by HRSA members ror image” double adaptors. These were outlawed at least 20 years ago but its amazing how many still turn up. They seemed like a good idea at the time but by design, one of the two outlets has Active and Neutral transposed. Of course, live-chassis radios are one of the biggest dangers to the inexperienced. The AC/DC radios that operated directly from a DC supply in some towns should be approached with caution. They don’t have a power transformer, so depending on the polarity of the mains power point, the chassis can be live. Even with a fully closed set, a knob can still fall off, exposing metal. Or even more unexpected, the grub-screw holding the knob may be long enough to touch. If the mains cord is frayed, don’t shorten it, as it may be a resistance wire, to reduce the input voltage. An isolating transformer is recommended but even this does not result in a 100% safe radio. Most HRSA collectors are from an electronics background, or receive assistance from members with the necessary expertise. At the Society’s regular auctions the HRSA complies with electrical safety regulatory requirements, including all equipment for sale displaying a safety notice (further details in the web references). eBay has changed the buying and selling of radios. Some collectors find greater access to interesting items. If you are tempted to give it a go, ask friends about safety and security issues. Be aware of statements like ‘not working – needs a valve – should be easy to fix’. Translation – I switched it on and smoke came out, so I’ll get rid of it. Or ‘Valve, New in Box’. This is sometimes described as ‘NOS’ (New Old Stock). While there are amazing numbers of never-used old valves still in existence, it’s quite common to find a faulty valve in a nice box. The reason? ‘Valve jockeying’, or trying new valves first before proper circuit analysis. This often achieved results, albeit temporary. Without proper circuit repairs, to repair the real fault, many new valves degenerated to the state of the replaced one. Due to the cost and inconvenience of securing a wide range of valves – and the chance valve replacement was not the solution – technicians and hobbyists changed each valve, placing the old one in the box. Unless the valve was in a very poor state, most were kept for valve-jockeying tests. If there was some improvement, then a new valve was purchased. Don’t plug it in and turn it on . . . A final safety tip: never turn on an old radio ‘to see if it works’. This is not only dangerous for the operator but can destroy a classic radio in an instant, reducing its value and restorability to near zero in one unwise move. Old parts such as capacitors (they were originally called condensers), transformers and resistors may have a short, so the radio ‘fries’. Instead of just turning on an old radio and standing back, check it over first, physically and electrically. Power transformers and the like are much harder to source than new, reliable, capacitors. Many advocate replacement of all the electrolytic and other suspect (especially paper) capacitors, as if they are not faulty now, they soon will be. Test the chassis for shorts and if possible, do a “Megger” test. For the inexperienced, ask someone who knows old radios to do this for you. For more information on restoring early sets, SILICON The restoration of this white ‘marbleised’ AWA case passes the closest inspection. The severity of the damage – even greater than the progress photograph on the left – would normally mean it would be thrown out, but sets like this are quite rare. 62  Silicon Chip siliconchip.com.au The Society’s activities include auctions, a quarterly magazine with information, circuits and trading pages, meetings around Australia, technical and historic talks, restoration workshops, construction projects, technical library, circuit service, participation in shows and events and a valve/component bank, all for just $27 a year. HRSA’s big show! A beautifully restored “Peter Pan” radio, model BKJ (19467), manufactured by Eclipse Radio, Melbourne. CHIP has a “Vintage Radio” column in every issue, written by HRSA member Rodney Champness. 50s optimism After the war, the world surged with new optimism, producing inventive, productive and colourful products. A major development was plastic, with all its colours and ease of production. Two radios came to the forefront – plastic mantels and radiograms (record players with radios in a beautiful wood console). Colour was everywhere in the kitchen and radios followed suit, with hardly a brown radio in sight – the only brown or other warm tones remaining were in the timber finishes of radiograms and TV sets, relegated to the loungeroom. Radiograms often have high-performance multi-band receivers but few are collected, due to their size. TVs often end up at the tip too or sadly are stripped and made into fish tanks. That was all the rage a decade or so ago! By the early 60s, transistor radios surged in popularity. Today, their prices are generally lower than the older valve models and the designs appeal to younger members, so there are collectors addicted to these battery portables. Many members of the HRSA mostly specialise in a genre or era – for example, military radios. Many have extraordinary knowledge and information on their speciality. This is shared and traded between members, one of the great advantages of the HRSA. There are also members that offer speciality services, such as repairs to components like speakers, wood or bakelite. Ray Hosking is the master of bakelite repairs and his work is shown here. On completion, his repairs are completely invisible (he can make a silk purse from a sow’s ear!). Bakelite is a strong material but eventually becomes more fragile. So the common practice of picking up sets by holding their bakelite top is not advisable – always carry radios held from the base. SILICON CHIP is a keen supporter of the HRSA’s goals and this is highly appreciated by all members, especially as many read SILICON CHIP. In fact one of the winners of the inaugural SILICON CHIP Excellence in Education Technology award, Lauren Capel, restored a radio and built a power supply, plus MP3 player and mini AM transmitter, drawing on information and advice from HRSA members. siliconchip.com.au To mark the 25th anniversary of the HRSA, the organisation is staging a huge national event in Melbourne next month (April). Located in the vast Holmesglen Conference Centre, cnr Batesford & Warrigal Rds, Chadstone, there will be displays and activities for members and the public. Highlights will include a radio display, stunning in quality and quantity, an old radio store, a battery store, continuous radio shows from a large room full of consoles, working portables on parade, posters, images of Australian radios and production, giant auction, swapmeet, guest speakers, radio films, valuations and much more. Some activities are limited to members only. Members have free entry both days, so membership is encouraged. The members’ only day is Saturday April 14, from 9 am and Sunday April 15th from 9 am. On the Sunday, public admission commences at 1 pm. Details can seen at the special event web site, www.ozradios.com The event will appeal to any people interested in electronics or vintage radio. Hope to meet you there – you’ll certainly find many people, past and present, from the SC Australian electronics industry to chat to. The HRSA magazine Radio Waves, is published quarterly, edited by HRSA life-member, Bill Smith. Features include radio collections, events, radio restorations, auctions, sale of new or used parts and historic radio stories. March 2007  63