Wireless of the Week (2026)

Formally operated in tandem with the 'Wireless of the Week' feature on the Keith Skues Radio show, this page now show-cases vintage radio repair stories and other associated news by myself and others. ~~~~~ Just for fun page ~~~~~
*for all enthusiasts of old radios* For many years I used to frequently write into the Keith Skues Program on the BBC with details of which vintage radio was listening to the show on. The feature was known as 'Wireless of the Week' and this page was originally established back in 2011 to supplement the radio show feature and show photo's, videos and a full write up of each weeks featured radio. Sadly, the Keith Skues show was axed in 2020, however due to the success of this page, I have kept it going, to show-case repair stories, restorations, and any other radio related news of interest. Friends, readers and followers are also welcome to message me with details of their own repairs or radio collections if they wish, and I will duly publish them on this page as well. I do not do this for any commercial gain, nor am I in any way connected to Keith Skues or The BBC, this is merely a bit of fun for like minded enthusiasts! Many thanks to the late Julia Leigh Golding for getting the page started back in 2011, and long may it live on in her memory. Anyone else who wants to make their own comments or add features or their own collections is more than welcome to do so.

21/07/2026

Hi everyone,

Hope you are keeping well and managed to catch the 'Out of Time' Show on coastal radio earlier, and that the music and Wireless of the Week feature was of interest. Next week, my Wireless of the Week will be this Ekco model PT378 transistor radio of 1963. This was the first transistor radio I ever bought, and as shown in the video is housed in an attractive blue and cream case, with neat carrying handle to boot. This video was taken recently, and shows the radio receiving the sad sound of the retune message that was broadcast on 1515 meters, Longwave, for three days after Radio 4 ceased programming on this wavelength. However, repairing this radio was a 10 year project, and so here's another chance to read an article previously published on here in Februrary 2020 detailing this. The only thing I have done since then is to connect an adapter to enable it to take modern PP3 batteries, as the PP7 type that these sets were designed for are all but unobtainable now. This will be my final post for a couple of weeks due to family commitments, so happy reading, and best wishes, Chris

Greetings one and All
Well, I'm back! Firstly thanks to everyone for your pateince during what has probably been the longest break in Wireless of the Week History. I can't go into details on here, but needless to say it has been a tough few weeks for me an my family, and although we're not fully back to normal yet things are nicely heading in the right direction. Hence for the first time in about a month, I can bring back Wireless of the Week! And what a way to do it other than with a feature on the very first vintage Radio I ever bought, an Ekco PT378, originally introduced in 1961 with Mullard transistors, and updated in 1963 with Newmarket Transistors. Bit of a story coming up here, so hope you’re sitting comfortably….(For some reason, probably an oversight on my part, this hasn't been featured on here for about three years, so enjoy!)
My version of the Ekco PT378 is the 1963 edition with Newmarket Transistors, and as shown in the the video she is portable sized, and housed a blue and grey Rexene covered wooden case. As you may well have guessed already, the first video shows her coming back to life while still being worked on, and the second one shows the completed job. This set first caught my eye in about April 2005, when I was walking past the Samaritans Charity shop in Ipswich. I noticed this old radio in the window, which I was really taken by, especially with its blue and grey case, gold speaker grill and round tuning dial. The shop was closed at the time, but I loved it nonetheless, so stopped and had a good look.
Three weeks later I walked past again, and it was still there – only this time the shop was open! So I decided to go in and ask to have a look. I saw there was a price on it of £15. (Bear in mind this was before the recession hit!) I ask if it works or not, to which one of the ladies replies: “Well surely, you wouldn’t want to actually use it, best just to keep it for display!” I reply that I like these things to work if they can, and I persuade them to lend me a screw-driver so I can take the back off and see what battery it takes. I then proceed to do this on the shop counter, and ask them if they mind waiting while I nip round to a shop to get a nine volt battery! Amazingly, they agree to this and I do so, only to find that I’ve got the wrong one! (A bit naive in those days, didn’t realize that it needed a PP7 battery when in-fact I had come back with the much more common PP3!) So I then make them wait again while I walk to another shop, further away and eventually came back with the correct PP7. I put this in, turn the radio on, turn the tuning control and immediately the shop is filled with the sounds of Classic Gold Amber on 257 meters! (The former Radio Orwell transmitter, now broadcasting as Smooth Radio.) I think the girls in the shop were as surprised as I was! I then agreed to buy the set – they kindly knocked it down again to £14 to help me with the cost of the battery! So off I went, and caught the bus home with it safely wrapped up in my rucksack.
On the bus I bumped into an old school friend and showed him – he was somewhat bemused, and commented on how ancient it was!
When arriving home, I told my Mum I’d done something adventurous – at first she thought I’d gone and booked myself a haircut! I had a ponytail back then…seems a long time ago now!
I can also remember showing the Ekco off at a local youth club where I volunteered at the time, however in the Autumn I rather foolishly tried to improve its performance. I should never have done this – I didn’t know what I was doing at the time, and ended up wrecking the poor thing. Hence it never appeared as a 'Wireless of the Week' until 2015. Despite various attempts over the years to undo the damage, I absolutely could not work out what I had done to the poor thing all those years ago – neither could a number of other much more experienced experts who know far more about this game than I do! (Which, to be fair, did help me to feel slightly better about my own failed attempts to repair her!)
However thanks to the kind actions of a certain gentleman in Southend in June this year the story now has a happy ending. I had been consulting the gentleman in question via e-mail about this radio, and he came up with a number of very helpful and well thought responses….sadly though none of them did the trick. So he kindly went one better for me….he found a scrap Ekco PT378 in his own workshop, packed it up and posted it to me in the hope that I could make one good one out of the two wreckages! And so the story took a new turn…..
I found the Ekco which had been sent to me was in-fact in much better condition than my example, and in-fact working (and indeed better than I could remember my own example having worked even before I wrecked it!) albeit with the on/off volume switch taken out of circuit, (due to being defective) and the tuning k**b missing. So after a bit of deliberation and further fruitless attempts to repair my own set I took the decision to put the two together, cannibalising my own one to complete the one which had been sent to me. Hence the on/off volume potentiometer, along with the waveband slider and metal backing were removed from mine, and fitted to the second set, as was the tuning k**b. I also noticed that two electrolytic condensers in the second set were none original - since my own set had the originals in still, and these were testing o.k on the meter, I decided to swap them over from my set, to the second one. (Note: to do this on battery sets is one thing, but I would be a bit more cautious about doing this with mains equipment.) This wasn’t a necessary repair to be honest, it’s just that I’m fussy and wanted to restore as much originality as possible to the second Ekco, and of course it would mean that yet another couple of bits from my original purchase all those years ago would be brought back to life! Hence this swap was done without too much difficulty, and the electrical repairs were complete – at long last I now had a fully functioning Ekco PT378, something I’ve been waiting for since 2005!
Following this, I of course re-assembled it back into the cabinet and then set about cleaning this – a whole evening was spent on this task, carefully using warm soapy water on the Rexene, and Brasso on the metalwork, hence a beautiful shine was obtained. Incidentally I have re-used the back from my original Ekco on my completed set – one because like I say, I’m fussy, and two there’s a slight difference on the internal label, and I wanted to keep the one I’d first set sight upon all those years ago!
So basically, what you see here in these videos is the Ekco PT378 that was sent to me by the kind gentleman in Southend, (to whom of course I am very thankful – I won’t mention his name, but he is hopefully reading this, and he knows who he is) but with several parts from my original purchase in 2005 added in to make it complete. Although I’m sad that my original example won’t work again in its own right, it’s pretty fair to say that the one sent to me was by far the best of the two examples, and I think that experiences of recent years suggest that whatever I did back in 2005 I almost certainly wrecked my original example beyond repair. I have kept it though – one as a reminder of mistakes made in the past (so they will hopefully not be repeated in the future) and two, because it’s the best possible source of spare parts should anything go wrong with my current example in the future! So whatever happens, at least bits of my original one will live on! The only thing that’s missing is the clear plastic frontage for the tuning k**b – sadly neither example had this, but it is usable without.
So in a nutshell, this 1963 example of the Ekco PT378 is powered by a PP7 battery (difficult, but not impossible to obtain) and covers Longwave and Medium-wave, with reception being obtained by an internal ferrite rod aerial. With a deep, clear sound, BBC Essex is loud and proud on 411 Meters, Medium-wave; hence I look forward to listening to Keith Skues on Sunday night. So here we have it, my first vintage radio, originally bought in May 2005, wrecked in Autumn 2005, finally making its Wireless of the Week debut in July 2015, and now having its third feature on the page on February 2020! Safe to say this has been by far my longest ever repair job!
Until next time,
Best Wishes,
Chris

16/07/2026

Greetings one and all

Next weeks Wireless of the Week on the Out of Time Radio show will be this Pye model 806 of 1938. Yes, I know it's only a few weeks ago since this set was last featured, but I am featuring it again so I can show this poignant (albeit slightly amaturish) video of it playing out The Westminster Chimes, a mere one hour before Radio 4 Longwave was discontinued. A piece of radio history fading into the past.....As described in the article below (originally published last year) this set has Push-button tuning, and a careful look at the video, will show that the 'Droitwitch' button is pressed.

That said, next Tuesday evening it will be fired up again, to play out the much happier sounds of 'Out of Time' with Eric White. , and I will be able to hear the show on the former 'Radio Normandie' pre-set. With the four Tone controls set to give a good Bass response, I expect the show to boom forth with pride. Happy Listening one and all!

ARTICLE ORIGINALLY PUBLISHED SEPTEMBER 2025:

Hi Folks
Well, as promised a little earlier, here’s my latest repair story. The Pye Model 806 was introduced in 1938 at the height of the boom in sets with Push-button tuning. Featuring full coverage of the Long, Medium and Short-wave bands, along with no less than six station pre-sets (for LW and MW stations) and four Tone-control pre-sets the specification of this set is somewhat impressive to say the least. However, this particular example is somewhat more complicated, as it has been quite heavily modified, (probably in the early 1960’s) as will soon become clear.
The original valve line-up of this set is TH4A (Frequency changer) TV4A (Magic Eye Tuning indicator) VP4B (Intermediate Frequency amplifier) TDD4 (Audio Amplifier) and PenB4 (Audio Output.) The rectifier is a DW4/350. But already this is where it gets complicated – Between the TH4A and the VP4B an additional plug-in I.F. coil has been added, with a valve socket to accommodate it (see photo 1) and an additional valve has been added – an extra TDD4. Additional modifications have included the addition of two rotary controls and a push button on the front (the two rotary controls appear to have once been wired one into the RF stage and one into the audio stage, but now are completely in-effective, the push-button switch is not connected to anything at all.) This has involved drilling holes in the front of the cabinet to accommodate them, which is a shame, but in fairness it looks to have been neatly and professionally done, and to a high standard at that. (See Photo 2)
So needless to say, quite a mystery going on here. You may recall that I restored one of these back in 2022 (see here for full details of that repair https://www.facebook.com/profile/100063285004857/search/?q=Pye%20806 ) however I was attracted to this one owing to the fact that my original 806 had an incorrect mains transformer fitted, making it prone to dangerous over-heating. In theory of course I could have had a new transformer built for it, but acquiring this set instead was undoubtedly a much cheaper (and simpler) option…. apart from all those modifications that is!
First job to do was to replace the mains lead as this was cracked and perished. I then powered up the set (the seller had mentioned that it was working, however it needed some attention as the sound was distorted) and sure enough it worked – some very slight distortion, but only very minor. The seller had suggested that this distortion may be due to an incorrect output valve having been fitted, however it actually turned out to be much simpler than that. (The output valve was in-fact the correct one after all.) An unusual feature of this set is the Expansion Indicator, which is a small 6.3-volt lamp, which is switched in and out of the audio circuit, by pressing the ‘Expansion’ button on the tone selectors section of the control panel. This brings the lamp into the audio tonal circuit, (in place of trader sheet marked Resistor 29, which provides negative feedback coupling when the Expansion lamp is not in use) thus creating sound expansion. In this case, however, the fitting had worked loose, causing the contacts of the lamp too short to chassis. Clearing this short, cured the distortion – and got the lamp working nicely – when the expansion button is pressed and the volume is turned up, it flickers in time to the speech and music, a pretty cool feature!
Following this, however, I observed another somewhat strange fault. I would have a station tuned in, (the pre-set buttons were also set up by this time – see photo 3 for a close up of these – note some of the station names and how the button of the selected station is illuminated!) when all of a sudden, the tracking would jump – each station would move up the dial by approx. 30 – 50 meters, and the push buttons would be thrown off tune. After a while, it would correct itself. This was eventually traced to a faulty capacitor (condenser) in the RF circuit – having sought advice on the issue I was able to trace the fault to a 0.002 uf Mica capacitor in the tuning section (on the Trader service sheet, this is C18 – Part Oscillator auto – circuit coupling) – even nudging it with the insulated end of a screw-driver would be enough to knock the fault on or off. Needless to say, this was promptly replaced.
Following this, however disaster struck – the magic eye that was in this set when supplied to me, was very dull, so naturally, I decided to replace it. I dug a replacement out (TV4A) which was a known good one and fitted it. Unfortunately, however I accidentally did the holding clasp up too tight the result being – you guessed it – the glass envelope cracked! A good Magic Eye valve completely ruined! After turning the air very blue I managed to search online (because of course I didn’t have another one going spare, now did I) and find a replacement for a good price, which thankfully worked. But an annoyance, nonetheless!
Then, it was a case of (once again) tuning in all the pre-set buttons. This is a case of using a screwdriver to tune in the corresponding coils and trimming condenser for each button. Each button covers a given section of the LW or MW bands, allowing up to a maximum of six stations to be tuned in. However, there was still a persisting problem – button six was only wanting to tune in ‘when it felt like it’ I tried repeatedly cleaning the contacts with WD40/contact cleaner – no joy. After much head-scratching, the mystery was eventually solved – and what a fluke – basically C17 (as listed on the trader sheet) is the fixed tracker for the MW Oscillator circuit, valued at 0.00055uf – this turned out to have an intermittent fault. So why was it only affecting one of the push-buttons you may ask? Completely by chance is the answer – it happened to be located right next to button six, and when button six was pressed, this would nudge it slightly, causing the fault to present itself. When one of the other buttons was pushed, it would be nudged back, causing the fault to clear! (Seriously, what are the chances??)
Needless to say, this condenser was replaced, the button tuned in, and the set is now performing nicely on all wavebands and all push buttons. – The first one I have tuned to Radio 4 LW (while it lasts) – the second one is blank, the third is tuned to Radio Caroline, the fourth tuned to Radio 5 Live (693 K/c’s, 433m) the fifth to Radio Five Live (909 K/c’s – 330 m) – Radio Five Live is of little use to me being that I am not a sports fan, however it was something to put on those buttons in an era when the MW is sadly becoming more and more devoid of stations. Finally, the sixth button is on my ‘pantry’ transmitter.
In future, I may fit a new frequency changer valve (TH4A) as the current one is prone to frequency drift, which of course can be annoying when using the pre-sets.
An additional job on this set was to wire a 160-ma fuse into the HT Supply. The idea/theory being that if a component short-circuits or overloads, the fuse will blow, thus removing any undue strain from the mains transformer. (A very expensive job if that burns out as any radio collector will know!)
But otherwise, a well performing set with coverage of every domestic frequency available at the time, some unusual features and four tone-pre-set buttons, which can be used in any combination. A pleasure to restore and to listen too. Hopefully the video will demonstrate this. – If you can excuse my appalling camera work that is!
Best wishes,
Chris

09/07/2026

Greetings one and all. My wireless of the week for the Out of Time show on Coastal Radio next week will be this Bush DAC 10. Introduced in January 1950, and continued to be manufactured until about 1957. A table-top sized valve radio housed in a brown bakelite case, the set can be powered from either AC or DC mains, and covers Long-wave and Medium-wave. However, it's not quite that simple, because in addition to the usual manual tuning control, the set also has three push-button tuning controls, each one of which can be permanently tuned to a station, thus making that station available at the touch of a button! In other words, an early form of pre-set tuning! (Can't see that taking off, can you!?) My set being a later version (1956 to be exact) she offers one pre-set for the Long-wave band, which is set to Radio 4 Longwave, and two for the Medium-wave - one covering 200-350 meters, the second covering 350 - 500 meters. Needless to say the latter has been tuned by me to Radio Caroline on 463 meters. (Well, had to be done, didn't it!) The push-button tuning feature made the Bush DAC 10 a popular choice by the Wireless for the Blind fund, a charity which dates back to 1928, and is to this very day continuing to provide radio and audio equipment for the blind or partially sighted. The fund was founded by Captain Sir Beachcroft Towse, VC, KCVO, CBE, who lost his sight in the Boer war, and was officially launched by Sir Winston Churchill on Christmas Day 1928. The video here was taken shortly before Radio 4 Longwave was shut down, and demonstrates the Push-button pre-set feature getting a last hurrah, during the last days of there still being a meaningful choice on them! For more information about the 'British Wireless for the Blind Fund' visit www.blind.org.uk The valve line-up is the same as that of the Phillips Bx 210, Bush DAC90 A and the Ferranti 745 (all featured on this page.) That being UCH42 Frequency Changer, UF41 I.F. Amplifier, UBC41 Audio Frequency Amplifier, UL41 Audio Output, and UY41 rectifier.

28/06/2026

Hi Everyone, having posted these videos on here a few days ago of my 1936 Philco model 444 'Peoples Set' recieving the final moments of BBC Radio 4 on 1515m, 198 K/c's Longwave, I thought I would make this next weeks 'Wireless of The Week' on the 'Out of Time' show on Coastal 105. So this is what I will be using to listen to Eric Whites show on the evening of Tuesday, July 7th, what follows below is another chance to read articles previously posted on this page one in 2016, sharing my personal memories of this set, and another one detailing the repair I carried out after she broke down in style back in 2020. Best wishes, and enjoy, Chris - P.S. More Radio 4 LW final moments videos to follow in the coming weeks - these are to be future 'Wireless of the Week's'

DECEMBER 31ST, 2016
Greetings one and all. My final Wireless of the Week entry for 2016, is a tribute to two very special people in the world of vintage radio. Firstly, my dear friend Tony Adams, who taught me a huge amount about vintage radio and electrical repair, having had a career in this field since 1946. He taught me almost everything I know about vintage radio, at his shop in Ipswich, which was in operation from 1967-2013. Mr. Adams died on December 29th, 2012, after a long illness. The very last radio he worked on was my Philco model 444 peoples set in the spring of that same year, hence this is now a very special radio in my collection - it's the last link to Mr. Adams and the happy years I had working in his shop.
Secondly, this entry is also a tribute to Gerry Wells, who died on December 22nd 2014 at the age of 85 after a short illness. He was easily the greatest radio collector and restorer of all time, having amassed a collection comprising 1,300 vintage radio's and similar memorabilia, at his London home, which is known by collectors and enthusiasts around the world, has been featured in the National media, and been an official museum for over 40 years. Gerry literally dedicated his whole life to radio and electricity, from the age of 2 he was said to be more interested in plugs, sockets and light fittings than the children's toys of the era. His obsession brought him many high's and lows throughout his life, but he was widely respected by many for his knowledge, passion, and desire to help others, with repairs, history lessons, and advice. Gerry is a tremendous, irreplaceable loss to the vintage radio world, I can only hope that at least some of his knowledge will live on in those of us who were privileged enough to have met him.
In 2002, Mr. Wells, published a most fascinating autobiography, and one of the radio's featured a number of times in this book is the Philco model 444 of 1936, which Gerry could recall coming on to the market for the very first time when he was just seven years old. So needless to say come tomorrow night I will be listening to the Keith Skues show on my example of the Philco 444, hence this is my Wireless of the Week this Week, as double anniversary tribute to these two wonderful men. In the book Gerry mentions a few repairs he carried out on one of these radio's as a teenager back in the 1940's, which proved helpful to myself and a couple of local friends who kindly helped me restore my example back in 2012. The Philco 444 was designed to be cheaper than most other radios on the market, it's purpose to make wireless more affordable. According to Mr. Wells' book there was a general outcry about the high price of radio sets in Britain at the time, hence the government of the day set a challenge to the radio industry to come up with something cheaper, the result being the production of the Philco 444. Initially, sales were poor, however a stroke of genius at the Philco radio co-operation picked up on the fact that 'People' was very much a Buzz-word at the time, hence they re-branded it the 'Peoples Set.' Following this, it was a huge success, and many still survive today in the hands of collectors. Housed in a stylish black Bakelite case (which in those days was cheaper than wood) this valve radio has coverage of the Long and Medium-wave bands, and despite being designed as a cheaper set of her time, she is still of good quality and with a sweet sound produced by the sets mains-energized speaker, BBC Essex is loud and proud on 411 meters, 729 K/c's in the Medium-wave band, thus enabling me to hear Keith Skues on this fine radio come tomorrow evening. Special mention needs to be made of one particular valve housed in the set. The PEN DD 61 is not only clever, but unique as well. Essentially it is three valves rolled into one, as denoted by its name. It comprises one Pentode and two diodes (DD - Double Diode.) The 61 pre-fix denotes that the valve heater is rated at six volts. Although the PEN DD 61 is not the only valve ever made that does more than one job, it is unique in that it was made exclusively for the Philco 444 and absolutely no other radio or piece of equipment in the world features it.
Since acquiring this set in January 2012, she has taken me on a lengthy journey of repairs, and at one point, electrocution. (Do not try this at home!) Initially, she worked well, but then failed suddenly. This turned out to be a short circuit across Condenser 4, which is coupled to the grid of the I.F. Valve. (A Philco 78.) Indeed, it really was a complete short. So this was replaced, but it became clear that further damage had occurred as a result of this, as the set still didn't work. In essence, what actually happened was a number of the aging condensers throughout the set failed, presumably due to not having been used for a long time. Many of these were replaced, but still very poor results! (There were three of us on the case by this point!) It seemed quite unbelievable - we would get whistles from the signal generator at the right times, and a very faint sound from Gold Radio on 257 meters, (yes, that is the old Radio Orwell transmitter, now changed over to Smooth Radio!) but nothing that anyone could listen to! After months of trails and tribulations, including replacement parts, retuning etc, we realized that the volume control had in fact failed! So a lot of this time the set had been working, we just couldn't hear it! A replacement volume control, followed by further re-tuning gradually brought the set back to life. Although there were further twists to the tale. Whilst moving the chassis, the back of my hand accidentally struck a metal-cased plug socket. Remembering that the golden rule with electricity is that it takes the quickest route to Earth, it is not surprising that I got a huge shock through the back of my hand. Being an AC shock this threw my hand off the source, causing me to smack my thumb on the tuning scale and make it bleed! (Don't worry, the radio was un-harmed!) Although I don't condone being electrocuted I'm pleased to say on this occasion I got away with it, but don't go trying it for yourself anyone, people aren't always that lucky! Later on though, there was another two twists to the tale. Shortly after the electrocution incident, the set decided to start tripping off the RCD breaker. This turned out to be caused by the mains filtering condensers, the exact same fault that had occurred in the Philco C-638 in 2011! - See entry about this set, don't I ever learn!:) So these were replaced. Then, just as I was about to return her to her case, she suddenly stopped working. This turned out to be a rather spooky re-occurrence of the initial fault, some three months earlier, the failure of Condenser 4. Thankfully, I caught it quickly this time, before any further damage could occur as a result. Just goes to show though, that you can go through the woods, to then have that initial niggling fault come back to haunt you again! All sorted now though! As an owner of two Philco Radio's it is interesting to note certain similarities despite them being at opposite ends of the market. I.e. similar valve line-ups (including Philco's own brand of valves) as well as the use of moulded condensers which are small bakelite blocks, each one comprising two - three condensers. As far as I know, these are unique to Philco, although if anyone knows different, it would be good to hear from you!
UPDATE NOVEMBER 2020
Well it was like this you see. Back in July I was sitting by my Philco 444 with a beer in me hand listening to a Radio Caroline North weekend, when part way through one of Dave Fosters programs, the sound suddenly dropped. Just as I got up to investigate, a loud hissing noise emanated from within the radio. Knowing this wasn’t good, I turned off immediately and unplugged. Next thing I knew there were plumes of smoke pouring out the back. Needless to say, my heart sank through the floor!
Later investigations confirmed my worst fears – short-circuited turns on the HT winding of the mains transformer. Unfortunately, transformer repair is a very specialist business, which requires specific equipment. Since I have neither the knowledge or equipment needed to do transformer repairs, I sent it away to a specialist.
It finally came back in October, having been completely re-manufactured, cleaned up and re-wound, in fact it barely looked recognisable - I was pretty impressed to be honest. Now, my side of the job was to begin, namely the somewhat complex job of re-instating it in the set and ensuring all the connections were put back into the correct places.
This of course was where the fun began. For those of you who don’t already know there are of course several dimensions to valve radio power supply. In the case of the Philco 444 for instance, you first have the mains input comprising of the mains and neutral connections going to the transformer. Hence these are your first two connections – these go across the ‘Primary’ coil. On the ‘secondary’ side of the transformer (see photo) there are, in effect multiple coils, each doing different jobs – you have the Low tension for the Rectifier valve, which supplies around 5 volts to the heater of this – hence two more connections (live and neutral again.) Next, you have the general ‘LT’ supply which is approx. 6 volts for the remaining valve heaters and the dial light. Finally, you have the ‘HT’ supply which is effectively a step-up from the mains delivering a total of approx. 350 volts to both the rectifier valve anodes (the rectifier and smoothing condensers then convert this to DC to form the HT supply for the remaining valves.) Needless to say, all these connections have to be exactly right, if not, at best the set won’t work properly, at worst it could be total disaster!
So I set to work, and once I was satisfied that I had everything connected where it should be, I then started to power up the set – through a variac, as this would enable me to power it up slowly and gradually, so if I had made any mistakes I would spot them before any serious damage was done.
Well in the first instance, it became obvious that something wasn’t right there was no sound, and I couldn’t help thinking that the dial light was not as bright as it should be. In addition to this, I couldn’t get any DC voltage on the HT line. The meter was showing 350 volts AC on each anode of the rectifier, but absolutely nothing on the HT line itself, a bit odd I thought as I was pretty certain there was nothing wrong with the rectifier, and there were no obvious signs of a short.
I decided to investigate one problem at a time, so I started with the dim dial light and dim valve heaters. A check of the meter revealed there was only about 2.5 volts on the L.T line. Well this would explain a lot, there’s supposed to be six! I wondered if at first, I’d connected the wrong wires to the LT – there was in fact three LT cables not two, and the third appeared to have two wires inside, maybe I’d connected the wrong one, and it was therefore not getting the full voltage? So, I tried swapping them around, but this made no difference. (Don’t worry I was powering up with the variac each time don’t forget!) I then decided to do some investigations with all the valves and the dial light removed (one, to try it ‘off load’ and two to ensure that no damage occurred to anything in the event of a mis-hap!) I still only had between two and a half and three-volts on the LT line. You will recall however that there were in-fact three LT cables and that one of these had two wires within it. I was finding that if I set the meter to ohms range and putting it across the one of the two wires on one side and one of the other LT cables on the other, I would get a resistance reading, but only about half what it should be! So, I decided to join the two wires (the ones which were within the same cable) together. This rewarded me with the full specified level of resistance across the LT coil. Powering it up again now revealed I had a healthy 6 volts on the LT line, and powering it up with the valves and dial light back in position now got these glowing to their full extent.
But still no sound, and still no HT! A look at the diagram made me realise I’d made a school-boy error. Whilst I had correctly connected the HT coil to the rectifier anodes, I had omitted to connect the center-tap to chassis, thus preventing any current from flowing. So, I corrected this, and began to power up again through the variac. Doing so revealed some DC voltage (albeit a bit low) on the HT line and finally, the sound of Radio Caroline coming from the speaker. Finally, on the home straight I thought, however all of a sudden, the already low HT voltage dropped further and the sound reduced slightly. I then realised much to my horror that one of the HT smoothing electrolytics (only fitted in 2012!) was smoking! Knowing that these are both dangerous and very volatile if they explode, I pulled the plug immediately, and gave it a moment. I then cautiously had a feel of it and found it to be burning hot. This I found a bit strange; it was only eight years old and been in regular use - no reason why it should fail. However, disconnecting it and checking with the meter suggested no signs of a short or overload on the HT line, but that the electrolytic itself was ‘leaky’. So, I fitted a new one and cautiously powered the set up again – much better this time – a nice healthy 325 volts DC on the HT line and stations galore! Whether the failure of the electrolytic was a co-incidence (most likely) or whether this was the reason the transformer failed is a bit of a mystery, but at least the set now lives again!
While the set was out of the cabinet, I took the opportunity to give it a bit of a clean and make some fine adjustments to the internal tuning padders, before returning it to the cabinet and bringing it back into service.
So, all in all a bit of a challenge, on a very important part of the collection, but both interesting and worthwhile – only the second time I’ve wired up a mains transformer and the first time I’ve done this since 2006.
Remember the offer still stands that if anyone reading this would like their own vintage radio-related article to appear on this page, please message it to me and I will make that happen for you.
Best wishes and keep safe everyone
Regards
Chris

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