Fullscreen HTML5Med Res (??MB)HTML4

VINTAGE RADIO By JOHN HILL Advice to the budding collector Over the last 12 months or so, I have dealt with most of the important aspects of restoring valve radio receivers. At this stage, it would be a good time to look back before going any further. A few additional comments could help those who may be considering taking up this unusual hobby. First, I should point out that one does not have to be an "oldie" well versed in valve technology to be able to collect, repair and enjoy old radios. At 52, I don't consider myself really old and when I started collecting (about three years ago), I certainly wasn't at all knowledgeable about valve technology. For this reason, I have tried to keep things fairly simple. I virtually started from scratch and I know that there is nothing worse than trying to digest information that is overly technical. My first repair My first radio repair was more good luck than good management and I repaired that set without any real understanding of what I did. A timber cabinet with several contrasting timbers was used to house this Operatic of about 1947 vintage. These radios were made in Adelaide. 18 SILICON CHIP This first restoration was on an old Radiola console that "worked" but not very well. A close examination under the chassis revealed two things of interest - a large redback spider and a paper capacitor with split ends. Evicting the redback and replacing the suspect capacitor cured the problems and the set worked quite well from then on. If I had not succeeded with that first repair I would probably have lost interest in vintage radios and found something else to do with my spare time. As it happened, I was able to repair that particular set and became so enthused that I went on to collect and restore many more old receivers. Servicing valve radios involves nothing more than searching for defective components. With my first restoration I was lucky that the problem was obvious enough to be seen. Unfortunately, this is not always the case and some receiver malfunctions can be quite difficult to cure unless one has a good understanding of valve technology. However, in most cases, one does not really need to have an intimate understanding of valve radios to be able to repair them. While such a comment may suggest that you don't have to know what you're doing, the fact remains that a lot of repairs can be made by simple logic, deduction and observation. Just running a check on valve heaters, resistors, chokes and speaker transformers will detect most valve radio problems, as detailed in previous columns. I have kept a logbook on my many repairs, listing the nature of the fault and the eventual cure. This is a particularly good idea for people Vintage Radio Kits & Parts ORPHEIIS *RADIO* Many hours were spent restoring this post-war Philips Radioplayer to as new condition and the effort certainly paid off. This set has a short wave band and performs extremely well. Suppliers of • • • • • VALVES RADIO KITS CAPACITORS RESISTORS BOOKS, ETC. Please send for our free catalogue ORPHEUS RADIO RSD 898 BALLARAT VICTORIA 3352 Ph. (053) 34 2513. Fax (053) 31 3412 FIX-A-KIT Kit Repairs - $1 5 per hour. Normal Rate - $30 per hour. No charge for kits that can't be repaired. 3 month Warranty on repairs. Construction - fixed or hourly rate. 1 2 Month Warranty on Manufactured Kits. Custom Designing, Manufacturing, Large or Small Quantitites. This little 5-valve Astor mantle set is from the early 1930s. Note the ornate timber cabinet and the simple dial markings. who, like myself, have lousy memories. It's good to have such a book for future reference. Dangerous voltages Vintage radio can be a dangerous hobby if you don't know what you are doing. In fact, you are literally flirting with death if you indiscriminately probe around under- neath the chassis of a live 240V ACoperated valve radio. When I started out in this hobby, I had a healthy respect for the underside of any mains-operated set - and still have! So far I have not had a single tingle from a radio set and I intend to keep things that way. I have no desire to get tangled up with either HYCAL INSTRUMENTS Design, Manufacture, Repair of Electronic Equipment. (02) 633 5897 (02) 92 6309 Fax (02) 925 0840 APB /1, 1989 19 An early post-war HMV 5-valve receiver. Once again, many hours of work have restored the Bakelite cabinet to as-new condition, These old sets were capable of good performance. the 240VAC supply or the high tension DC. My advice to the novice enthusiast is to first learn where to find the 240VAC and the hightension DC connections. They are the ones that bite and it is important to know where they are before tinkering. As one progresses from one repair to another and reads up on old valve literature, the mysteries of valve technology will disappear. The main problem when changing from modern radio circuits to valve radio circuits is the big difference in operating voltages. If you are accustomed to solid state circuitry, it's easy to become complacent. In this type of equipment, the primary side of the power transformer (assuming that the set has one) is the only nasty spot that is likely to be encountered. And even then, it will most likely be well insulated. 20 SILICON CHIP This 5-valve Airzone is a classic mantle radio from the late 1930s. This particular set is housed in a Bakelite cabinet and features a rather ornate loudspeaker grille insert. Valve equipment on the other hand demands far greater respect and anyone working on it for the first time will need to be constantly on the alert. Just one moment of inattention could result in a nasty shock. Incomplete sets A problem that sometimes confronts a radio restorer is the set that someone else has tinkered with beforehand. In such cases, the radio may have had a number of components removed or disconnected and unless a circuit is available, there is little hope of the novice repairman knowing what components need replacing and where. These sets often end up in the too hard basket. In such cases, it's best to try to track down a circuit diagram. But above all, the vintage restorer has to be determined rather than super intelligent or good looking. If anyone wishes to restore old radios without previous experience in that field, there's no real reason why they can't. Most will succeed if the desire to do so is there. I would even go so far as to say that, as a hobby, vintage radio is probably a far more enjoyable pastime for the novice than it is for people experienced in electronics. For the novice, everything is a new and exciting experience. On the other hand, a radio-TV serviceman may find that vintage radio is little more than an extension of his everyday work. Collecting Although there are many thousands of old valve radios (both working and not working) to be found, they are getting scarcer every day. With this thought in mind, I spend a good deal of my spare time collecting whatever I can. It will take several years for me to restore This photograph is of an early postwar 5-valve Airzone. Valve radio receivers of this era were of particularly good quality. Buy direct from Australia's leading manufacturer and save on quality AVTEK Modems. A range of 16 internal & external modems . from low priced manual to fully automatic 2400 bps models complete with power supply, instructions and telephone connections. Designed and built in Australia, all Avtek Modems are guaranteed, with service and technical support available direct from Avtek. CALL TODAY ON 008 25 2754 or (02) 888 5333 TOLL FREE SYDNEY RESIDENTS For further information and to see how much you can save on the best modem for your needs. ll&J 14VTEK DATA COMMUNICATIONS (A Member of the NetComm Group of Companies) Another receiver from the early 1930s - a 4-valve Airzone. This style of radio is much sought after by collectors for it has real vintage radio appeal. the receivers that I have so far collected. Whilst it is not hard to locate and buy valve radios, the really collectable ones are difficult to find and it is now almost impossible to obtain old receivers from the mid-1920s era in good condition. These truly antique radios are mostly in the hands of collectors and not many come up for sale at house auctions like they did 20-30 years ago. However, despite the lack of these genuine antiques, there are still lots of interesting and very collectable radios from the 1930s to be had if one looks around. In the past two weeks I have obtained four such sets ranging from 1933 to 1938. All are restorable but only one was in "going" order. Any radio that is half a century old or older must be considered a collectable item. That said, there's nothing to stop you from restoring an early postwar radio if you come across an interesting model. If reader response is anything to go by, there is a lot of interest in vintage radio. Some collectors have been at it for 30 years or more but most, like myself, have only recently joined the ranks. Increasing interest in valve radios has seen the p_rice of old receivers at least triple in the past two years. No doubt, some of the renewed interest has been generated by this column. Interest in vintage radio has been such that, a few years ago, the Historical Radio Society of Australia was formed by a group of keen collectors. The society has attracted world-wide membership and has brought together a number of vintage radio collectors who may never otherwise have met. Next month (and in future columns), we shall get back to the practical aspects of collecting and restoring vintage radios. There's lots of topics yet to discuss on this fascinating hobby. Finally, I have included photographs of some of my radio treasures with this month's column. There is nothing like a picture of a nice old radio to keep interest and enthusiasm high. ~ APRIL 1989 21