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Restoring a Vintage Televisi With Australia celebrating 50 years of television last year, I thought I should celebrate the occasion and restore a TV set that was around not long after it started. But like the hare in Mrs Beaton’s cookbook, I first had to catch my set . . . I n my quest to find a television to restore, I had a particular one in mind – an AWA Model 229, from around 1958. My grandparents had owned one back then; in fact it was their very first television. They were the second house in the street to have a TV set and early on they had made many new friends thanks to that television! Back then television was still magic and somewhat of a mystery to most people. Crowds used to gather on the footpaths outside retailers just to watch the TV sets in the window (often with no sound!). I had an old black and white picture of the AWA, so knew what to look for. When one turned up on eBay, I just had to have it. One problem: I’m in Sydney and it was in Melbourne. So having won the auction, I arranged to have it freighted to Sydney. This cost nearly three times as much as the set. What have I done? The set duly arrived about a week later. It was as described on eBay and bearing that in mind, I knew it would take a fair amount of work before this would be a working clean example of a 1950s television. The set, while all there, was dirty. The set had apparently been stored in a damp location as much of the 20  Silicon Chip This old, grainy photograph was the picture that started it all. I wanted one of these AWA Model 229s, just like my grandparents had back in 1958 siliconchip.com.au ion By Timothy Stuart veneer on one side had lifted; some corrosion on the chassis was evident and other components had suffered, which I’ll mention later. And not least were the many bugs that over the last few decades had taken their last breath between the screen and the safety glass. Before starting any type of repair I like to clean the dust off the chassis, remove all the valves and check for anything that’s obviously missing. Having removed the chassis from the cabinet and then getting rid of the dust using some paint brushes, a vacuum cleaner and a damp cloth, I then washed all the valves, being careful not to rub off the delicate valve number markings. One valve in the tuner (a 6U8) was obviously gassy (a white/grey look inside) and was replaced with a new one. I next turned my attention to its underside. Lots of paper and wax With all vintage televisions and radios that I restore, I tend to favour a complete replacement of the paper and electrolytic capacitors. While there is some argument from the purists about doing this (polyester capacitors weren’t invented in the 1950s!), I find I end up with a much more reliable set and hopefully one I won’t have to siliconchip.com.au This is how it arrived from Melbourne after the successful eBay bid. It looks to be in pretty good condition but notice the peeling veneer (lower right). And there was a fair bit of damage inside. This photo doesn’t do justice to the legion of dead bugs between the screen and safety glass! repair again for a long time. I use tubular metallised polyester capacitors for the paper replacements which, while smaller than the originals, don’t look too out of place under the chassis, as compared to the more common ‘orange drop’ type capacitors. Following the paper caps, I replace all the electrolytics. Most high voltage electrolytics in vintage TVs are of the chassis-mount (can) type. I leave these in place on the chassis but disconnect them. This means there are no holes in the chassis, where there would have been had I removed them. Modern electrolytics are very much smaller and can be easily wired in under the chassis, often using the terminals on the old capacitors as tie points. Some restorers go to the trouble of removing the “innards” of the old can electros and mount a modern one inside the can. But not me! Spending a few hours replacing these components is very worthwhile and often a TV will be brought back to life just by replacing all the capacitors. Resistance is futile! Following the capacitor replacement, I then turn my attention to the higher value resistors in the set. Experience has shown that replacing all resistors 100kW and over will also greatly enhance the chances of the December 2007  21 television working as it should when first switched on. Many old resistors over this value ‘go high’ with age and cause strange effects on the picture and ineffective contrast, brightness, volume controls. Moreover, old high value resistors tend to go even higher in value as they warm up, causing all the settings to drift as the set warms up. In undertaking the resistor replacement, I found a number to be burned out, no doubt due to increased current flow caused by the old paper capacitors being ‘leaky’. Check those fuses! Another thing I always do is check that the correct fuse values are fitted. Many times I’ve found they’ve been replaced by a nail, paperclip or something like a 15A fuse where it should be a 1A. Next comes the “smoke test” – powering up the old set for what could be the first time in decades. Use a variac To power a set up for the first time, I always use a variac. This allows me to detect anything wrong before it fails catastrophically and causes damage to other components. I always power a set up in four stages. The first stage is with no valves installed, which checks that the power transformer is OK and that all secondary voltages are present and correct. The second stage is to gradually increase the input voltage to 240V. In the case of the old AWA, having run the set for an hour the transformer was warm but showing no signs of distress. Note also that old television sets usually had transformers with many input (primary) voltage taps. To increase the tube brightness, unscrupulous servicemen would often change the tap from 240V to 220V, increasing the secondary voltages in turn to levels far above the design voltage. So this is another thing to check before you power up the set. Valves go back in Stage 3: having passed the transformer test, it was time to plug in the valves. Initially, I start with just the rectifier valve(s). Slowly powering up the set again revealed nothing smoking or otherwise in distress. Measuring the rectified high tension (HT) voltages 22  Silicon Chip I was lucky: I had a complete service manual and circuit diagram to help me. indicated that all appeared well. Next check is with all valves installed with the exception of the high voltage rectifier, damper diode and horizontal output valve. Again, the set passed this test. Finally, with the remainder of the valves installed, the chassis returned to the cabinet and the picture tube and speakers connected, powering up yet again, resulted in a more or less completely working set. It works! With an antenna connected, I could now see a picture on the screen and had audio as well. However, there were a few problems still to resolve. The picture needed alignment, the siliconchip.com.au in vintage televisions is usually relatively simple and I quite easily located the problem in a low value HT feed resistor. Replacing it with a new one completely removed the crackle from the audio. After having done the picture alignment and centring, it was time to watch television, 1950s style. The pretty parts While I had been busy working on the electronics, a friend had been busy with the cabinet. It was in generally good condition, so I felt there was no need to do a full restoration. The veneer was re-glued and the interior of the cabinet vacuumed, brushed and wiped with a damp cloth. An oiling inside and out makes the timber look like new and moisturises the dry wood at the same time. The cleaned-up cabinet, although not brand new looking by any means, is very presentable and is still very original. Polishing and cleaning The accumulation of several decades of dust. The first step in restoring any old TV set is to get it as clean as possible without doing any (further?) damage. Contrast this photo with the cleaned (and restored) version overleaf. While the picture tube was out, the tube and safety glass were thoroughly cleaned and many expired bugs removed. The screen mask was also carefully cleaned. In this set it was made of plastic so had to be treated very carefully. The difference this made to the look of the front of the set was amazing. It was starting to look nearly new again! vertical hold and volume pots were very noisy, there was a noisy crackle in the audio and one of the speakers wasn’t working. I put most of these faults down to the television having been stored in a damp environment. Fortunately I had an almost direct replacement in stock for the faulty speaker, so I attached the speaker transformer to the new one and it fitted nicely into the original mounting holes and speaker opening. The vertical hold pot was replaced but the volume put was a different matter. Being a dual gang, concentric, switched type, replacements are almost impossible to find these days and so removal, taking apart and cleaning is the only option. So far this seems to have been very successful. Snap, crackle, pop! The last problem to fix was the loud crackle in the audio. The audio circuit siliconchip.com.au Some may argue the modern polyester capacitors (yellow) look out of place in a vintage set but you simply cannot trust the original paper capacitors. I make it a rule to replace them and high voltage electros and it has paid off every time. December 2007  23 Inside and outside the restored AWA. Above is the fully cleaned out and repaired (where necessary) chassis – though I was quite lucky with the relatively small amount of work necessary. You can’t see the repaired veneer in the photo at right but looks every bit as good as the rest of the set. The final touches The final touches included cleaning all the front panel control knobs, the aluminium front panel and finding some suitable replacement screws and bolts to hold the chassis in properly and the back cover on. What’s on the box? Finally it was all back together and I could settle back to watch TV 1950s style. This must have been a cosy family experience back then. With its small 17” screen, one has to sit relatively close for comfortable viewing. Still, maybe that’s not such a bad thing. Bring back 1958 I say! The end (or is it the beginning?) To conclude, although this restoration took place over a number of weeks and was somewhat time intensive, I’m very pleased with the final result. I should also point out that I had access to a service manual and circuit Silicon Chip Binders REAL VALUE AT $13.95 PLUS P & P These binders will protect your copies of SILICON CHIP. They feature heavy-board covers & are made from a dis­tinctive 2-tone green vinyl. They hold 12 issues and will look great on your bookshelf. H 80mm internal width H SILICON CHIP logo printed in gold-coloured lettering on spine & cover H Buy five and get them postage free! Price: $A13.95 plus $A7 p&p per order. Use the order form at right or call (02) 9939 3295; or fax (02) 9939 2648 and quote your credit card number. (Binders are only available in Australia and sent to an Australian address). diagram for this set, which made the restoration a lot easier. Lastly, although I’ve heard many stories about hard-to-find parts like line output transformers for vintage televisions I must have been lucky. Of all the televisions I’ve restored I’m yet to come across any with faulty transformers or picture tubes. That has been very good for me, as restoring a set with such faulty parts would require another one to scavenge parts from. SC Enclosed is my cheque/money order for $________ or please debit my  Visa    Mastercard Card No: _________________________________ Card Expiry Date ____/____ Signature ________________________ Name ____________________________ Address__________________________ __________________ P/code_______ Silicon Chip Publications, PO Box 139, Collaroy NSW 2097 24  Silicon Chip siliconchip.com.au