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Catkins · 8th Dec 2018, 5:07 am

Hi everyone,

Back in 2014, Steve Harris advertised a pre-war 1938 Murphy A56V television for sale, for the low price of £2950 (as pre-war televisions go). There was of course a reason for the low price, the A56V didn't have a working CRT, and it was a bit of a wreck. In "Airwaves" of Apr/Jun 2014, Steve described it thus "It is far from pristine condition ... If this was a Murphy radio of the same year, in this condition, it would struggle to make it to the bargain basement page, more likely it would be dumped in the store to be raided for any useful parts".

Being rather deterred by that description, and the associated photographs I did nothing, even though I was tempted by the fact it was a pre-war Murphy television and the only one I'd ever seen come up for sale. To my surprise it appeared in the next Airwaves (perhaps everyone else too was deterred by its state). I rang Steve Harris up, booked an appointment to view it, and having taken pity on its state (it really was almost a lost cause), decided it needed it needed to go to a good home, and took it home with me. I was undoubtedly biased by the fact Murphy is my favourite 1930s manufacturer, and it was probably the only chance of getting a pre-war Murphy television, but it was still a wreck.

When I got the set home, I stripped out all the electronics to enable the cabinet to be woodworm treated, the woodworm in the cabinet looked mostly historic but I was not 100% sure, and it is always better to veer on the safe side (the cabinet of the previously restored HMV 904 again looked to have historical woodworm, but, it proved to be still active). This allowed me to have a good inspection of the condition of the electronics. In fact I had already had one surprise when removing the electronics, as I found a detached mica-capacitor in the bottom of the case, which I was quite sure hadn't been there before the journey home, which didn't bode well for the level of corrosion. The first thing, perhaps obviously, was to discover where the mica-capacitor had come from. I found the possible place, but, in fact found 3 places where the mica-capacitors were missing, simply leaving two corroded "legs".

The inspection showed many of the capacitors/resistors were showing corrosion, with a couple attached by one leg only. Some of these, if still in spec, could be carefully repaired. All of the wiring was completely rotten, and would all need to be completely replaced. The wirewound trimmer pots in the chassis were corroded and open-circuit. The pots mounted on the cabinet were very rusty and stiff, but might be repairable if stripped down. The transformers on the power supply unit (Mains and EHT) and on the main chassis (frame and audio output), were completely rusted and probably needed rewinding. The deflection coils were in a similar state. The CRT is mounted and clamped, and the focus and deflection coils adjusted, via some fairly elaborate mechanism, and all of that mechanism was rusted solid and would not move. The tuning control (one of the occasional controls) which physically trims the local oscillator inductance by moving a brass rod was also rusted solid and would not move. The inductances/air-coils within the chassis showed some signs of corrosion, but I could not inspect the coils within the air-cans, without removing the air-cans which was beyond this relatively quick inspection.

Beyond that, all metalwork was completely rusted to a high degree, without any plating remaining. The power-supply chassis and the main chassis are painted, rather than plated. I initially hoped this paintwork could be saved, but examining the paintwork under a strong light showed the chassis to be heavily pock-marked with extensive rust underneath the paintwork. An experiment with a blunt screw-driver showed the paintwork easily came off revealing a layer of rust underneath (in a hidden part of the paintwork which was in a better condition than elsewhere because it had been relatively protected).

The set on this inspection thus turned out to be in a bit worse condition than even I expected, but, I already knew it was in a bad state, and so it didn't really change anything. If I was going to restore the set, it would be a massive undertaking, requiring a complete strip down of the set, and of the individual components themselves and complete rebuilding, before it would ever work again. It really was only on the edge of restorability and maybe a little bit beyond. If I thought the restoration mght fail, it in fact might be better to leave it as an unrestorable but untouched display item only.

At that time in October 2014, I was in the middle of restoring a 1938 HMV 904 television. This television too had numerous problems due to rust and corrosion (although not as bad), and I had got disheartened. I had spent over 30 years restoring 1920-1940s radios, but this HMV 904 was my first foray into television restoration, and I wondered if I should have attempted something easier for my first television restoration. So I started to look for another pre-war television to work on, and then found the Murphy A56V which was obviously much much worse. Paradoxically this did the trick, in respect to the fact I discovered I could be in a far worse position, and so persevered with the HMV 904 restoration with renewed enthusiasm, and succeeded with the restoration after about another year of work. My experience with that restoration is written up elsewhere on this site (https://www.vintage-radio.net/forum/...d.php?t=115533).

So at this point in October 2014 I simply put the Murphy A56V back together after woodworming, to wait and see how I faired with the HMV 904 restoration.

In November 2015, after the successful restoration of the HMV 904, I had to decide whether to attempt a restoration of the Murphy A56V, knowing it would be an even more difficult task. Flushed with the success of the HMV 904 restoration, I decided I could do it, and in fact as it was going to be a rebuild anyway, it would be a good opportunity to restore it to pristine condition. This was one set where a minimal restoration preserving patina simply wasn't possible, as no patina existed having disappeared under thick layers of rust years ago (preserving patina is one thing, "preserving" rust is another, I believe rust should always be treated/removed and the resultant metal treated to protect it against further rust, and if you do that, you may as well refinish it to the original condition).

I started the restoration in November 2015, and I finished it in November 2018, which makes just over 3 years from start to finish, which I think in anyone's book is a long time.

But I think the attached photographs show it was worth it. As I'm limited to 5 photos per post, I have attached 2 photos showing the original state, 2 showing the current state, and a photo showing the restored television displaying the test card. The CRT is a replacement CRM92, rather than the original CRM91 which was broken, and the CRT mounting has had to be adapted to accommodate the different CRT dimensions.

This is a video of the television on You-Tube https://youtu.be/8XaaeC7idIQ.

Further posts if anyone is interested, will show more photos of the restored television, and a description of the work undertaken.

8th Dec 2018, 5:07 am	#1
Catkins Pentode Join Date: Feb 2015 Location: Chepstow, Monmouthshire, UK. Posts: 234	1938 Murphy A56V television restoration Hi everyone, Back in 2014, Steve Harris advertised a pre-war 1938 Murphy A56V television for sale, for the low price of £2950 (as pre-war televisions go). There was of course a reason for the low price, the A56V didn't have a working CRT, and it was a bit of a wreck. In "Airwaves" of Apr/Jun 2014, Steve described it thus "It is far from pristine condition ... If this was a Murphy radio of the same year, in this condition, it would struggle to make it to the bargain basement page, more likely it would be dumped in the store to be raided for any useful parts". Being rather deterred by that description, and the associated photographs I did nothing, even though I was tempted by the fact it was a pre-war Murphy television and the only one I'd ever seen come up for sale. To my surprise it appeared in the next Airwaves (perhaps everyone else too was deterred by its state). I rang Steve Harris up, booked an appointment to view it, and having taken pity on its state (it really was almost a lost cause), decided it needed it needed to go to a good home, and took it home with me. I was undoubtedly biased by the fact Murphy is my favourite 1930s manufacturer, and it was probably the only chance of getting a pre-war Murphy television, but it was still a wreck. When I got the set home, I stripped out all the electronics to enable the cabinet to be woodworm treated, the woodworm in the cabinet looked mostly historic but I was not 100% sure, and it is always better to veer on the safe side (the cabinet of the previously restored HMV 904 again looked to have historical woodworm, but, it proved to be still active). This allowed me to have a good inspection of the condition of the electronics. In fact I had already had one surprise when removing the electronics, as I found a detached mica-capacitor in the bottom of the case, which I was quite sure hadn't been there before the journey home, which didn't bode well for the level of corrosion. The first thing, perhaps obviously, was to discover where the mica-capacitor had come from. I found the possible place, but, in fact found 3 places where the mica-capacitors were missing, simply leaving two corroded "legs". The inspection showed many of the capacitors/resistors were showing corrosion, with a couple attached by one leg only. Some of these, if still in spec, could be carefully repaired. All of the wiring was completely rotten, and would all need to be completely replaced. The wirewound trimmer pots in the chassis were corroded and open-circuit. The pots mounted on the cabinet were very rusty and stiff, but might be repairable if stripped down. The transformers on the power supply unit (Mains and EHT) and on the main chassis (frame and audio output), were completely rusted and probably needed rewinding. The deflection coils were in a similar state. The CRT is mounted and clamped, and the focus and deflection coils adjusted, via some fairly elaborate mechanism, and all of that mechanism was rusted solid and would not move. The tuning control (one of the occasional controls) which physically trims the local oscillator inductance by moving a brass rod was also rusted solid and would not move. The inductances/air-coils within the chassis showed some signs of corrosion, but I could not inspect the coils within the air-cans, without removing the air-cans which was beyond this relatively quick inspection. Beyond that, all metalwork was completely rusted to a high degree, without any plating remaining. The power-supply chassis and the main chassis are painted, rather than plated. I initially hoped this paintwork could be saved, but examining the paintwork under a strong light showed the chassis to be heavily pock-marked with extensive rust underneath the paintwork. An experiment with a blunt screw-driver showed the paintwork easily came off revealing a layer of rust underneath (in a hidden part of the paintwork which was in a better condition than elsewhere because it had been relatively protected). The set on this inspection thus turned out to be in a bit worse condition than even I expected, but, I already knew it was in a bad state, and so it didn't really change anything. If I was going to restore the set, it would be a massive undertaking, requiring a complete strip down of the set, and of the individual components themselves and complete rebuilding, before it would ever work again. It really was only on the edge of restorability and maybe a little bit beyond. If I thought the restoration mght fail, it in fact might be better to leave it as an unrestorable but untouched display item only. At that time in October 2014, I was in the middle of restoring a 1938 HMV 904 television. This television too had numerous problems due to rust and corrosion (although not as bad), and I had got disheartened. I had spent over 30 years restoring 1920-1940s radios, but this HMV 904 was my first foray into television restoration, and I wondered if I should have attempted something easier for my first television restoration. So I started to look for another pre-war television to work on, and then found the Murphy A56V which was obviously much much worse. Paradoxically this did the trick, in respect to the fact I discovered I could be in a far worse position, and so persevered with the HMV 904 restoration with renewed enthusiasm, and succeeded with the restoration after about another year of work. My experience with that restoration is written up elsewhere on this site (https://www.vintage-radio.net/forum/...d.php?t=115533). So at this point in October 2014 I simply put the Murphy A56V back together after woodworming, to wait and see how I faired with the HMV 904 restoration. In November 2015, after the successful restoration of the HMV 904, I had to decide whether to attempt a restoration of the Murphy A56V, knowing it would be an even more difficult task. Flushed with the success of the HMV 904 restoration, I decided I could do it, and in fact as it was going to be a rebuild anyway, it would be a good opportunity to restore it to pristine condition. This was one set where a minimal restoration preserving patina simply wasn't possible, as no patina existed having disappeared under thick layers of rust years ago (preserving patina is one thing, "preserving" rust is another, I believe rust should always be treated/removed and the resultant metal treated to protect it against further rust, and if you do that, you may as well refinish it to the original condition). I started the restoration in November 2015, and I finished it in November 2018, which makes just over 3 years from start to finish, which I think in anyone's book is a long time. But I think the attached photographs show it was worth it. As I'm limited to 5 photos per post, I have attached 2 photos showing the original state, 2 showing the current state, and a photo showing the restored television displaying the test card. The CRT is a replacement CRM92, rather than the original CRM91 which was broken, and the CRT mounting has had to be adapted to accommodate the different CRT dimensions. This is a video of the television on You-Tube https://youtu.be/8XaaeC7idIQ. Further posts if anyone is interested, will show more photos of the restored television, and a description of the work undertaken. Attached Thumbnails