1931 AWA 45E Radio - It Stopped Working!

[@dave_yeg8596]

when i smell something burning it usually means dinner is ready. thx for the upload agn.

[@DavidTipton101]

Haha... that might have been it! Thanks Dave 😄

[@ninaevans4501]

My missus NEVER burns dinner (Wayne, from Wayne & Nina commenting). The last time I complained, I wore the bacon, eggs and hash browns as a hat. Only kidding. Wayne 😵😵😵😵😵😄😄😄😄😄👍👍👍👍

[@maryrafuse2297]

David Tipton like our own Mr. Carlson is a real character. What a beautifully designed radio! Sending love to our Commonwealth Cousins from Canada.

[@DavidTipton101]

Thanks Mary. I was watching Paul this afternoon 🙂

[@ninaevans4501]

Here, here! From Ipswich, Suffolk, UK 👍👍👍👍👍👍😊😊😊😊😊❤️❤️❤️

[@chrismielke219]

hope that problem doesnt occur again Dave! Thats a nice radio. Great restoration

[@DavidTipton101]

Thanks Chris. So far... so good 👍🙂

[@chrismielke219]

@@DavidTipton101 Dave, is there any way i could buy a radio from you?

[@DavidTipton101]

Maybe, where are you located, do you have a particular radio in mind?

[@chrismielke219]

@@DavidTipton101 How about the Philips L3X73T-03? I really would like one of your radios you have done, and i dont currently have an Austrailian Radio. I am in the US, 53188 postal code.

[@DavidTipton101]

That was made in Holland and sold by Philips Australia.

[@ceebee23]

oh david .... a re-repair ... an encore!! great to see you back

[@DavidTipton101]

Thanks Chris 😀

[@paulsto6516]

That's one beautiful radio chassis! Thanks for sharing.

[@DavidTipton101]

Thank you Paul 🙂

[@Woffy.]

Strange set in a lovely cabinet, nice work David. Just calculated this, £39 in 1931 is equivalent in purchasing power to about £3,329.42 today, over 93 years. Wow Expensive.

[@DavidTipton101]

Yeah, it would have been out of reach for most people. Thanks Woffy 🙂

[@clasicradiolover]

I was wondering about that.$4099.51 in US Dollars

[@clasicradiolover]

$6368.85 Australian

[@Jan_Talcott_100]

Good video. Love watching you troubleshoot. More videos, please.🙂

[@DavidTipton101]

Thank You Jan 🙂

[@electronicsoldandnew]

Really frustrating when the fault comes and goes, but that’s part of the fun 😊 I see that in your background you were also taught to apply the “smack to the head” method. Works with lazy kids and sometimes equipment too 😂 I usually apply one good smack to the side of the equipment, but your bongo drum system seems much more refined. Learnt something today 😊

[@highpath4776]

whacked a microwave with appearing to have a stuck overheat protect or relay switch, got it working for dinner

[@DavidTipton101]

Haha... I like to be innovative Manuel, my bongo drum technique often pays dividends, sometime not so much 🙄 This one had me worried, I wasn't sure I fixed it but it still works so fingers crossed. Thanks Manuel 👍🙂

[@jamesbruno5896]

Nice repair David, take care!

[@DavidTipton101]

Thanks James 🙂

[@ellesmerewildwood4858]

A beautiful cabinet and a lovely job you did in the original restoration. You do still have some music stations playing some good music on AM where you are so can enjoy having this radio on daily. I kept wondering about that nasty black stain on that choke. As for the intro...fantastic fun, and reminded me, time to let out my inner child again, I'm sure I've got some crayons around here somewhere.

[@DavidTipton101]

Hello Ellesmere. We have one full time music station and one that plays a few songs an hour amongst some very interesting talks and interviews. The stain is a bit of pitch used to pot the chokes. I was in a silly mood when I did the intro, thanks 😄

[@chrislawrance8700]

Intermittent faults are always the most difficult. So pleased you got the satisfaction of finding the fault by the end. Great to have you back Dave.

[@DavidTipton101]

Thanks Chris 🙂

[@Daniel_cheems]

Welcome back Dave! This video was great.

[@DavidTipton101]

Thanks Daniel 🙂

[@mauricedarmody4424]

Love the sense of humour, you’re a credit to your country. England

[@DavidTipton101]

Thank you Maurice. Your support is greatly appreciated 👍🙂

[@roberthart8933]

Hi David listening to an almost 100 year old radio every day is a special treat. Apparently they used to hum a lot. An old chap told me many years ago that sets hummed a lot. You would walk into the room a the hum was pervasive. Apparently electrolytics weren’t available in 1931. And I have also has directly heated valves develop shorts between the filament and other electrodes. They stretch with age and can short. 5y3 especially

[@DavidTipton101]

Hi Robert, thanks. The hum isn't that noticeable when the set is running. The speaker doesn't have a humbucker as far as I can tell but I think I subbed in a PM speaker and the hum was still there. It starts as soon as power is applied, so it's coming from the directly heated 80 valve. I don't recall if I tried a different 80 in there, worth a try. I know others working on this chassis have struggled with hum too 🙂

[@jacksmid5322]

I have enjoyed watching all the videos on this radio David, I have a chassis and speaker the same in the bottom of my spare bedroom cupboard, only TRF I have.

[@DavidTipton101]

Thanks Jack. TRFs are easy to work on 👍🙂

[@aa1ww]

Another sane and sensible troubleshooting video. Your calm and patient approach including a bout with the tubetester is truly admirable.

[@DavidTipton101]

Thanks Jeff 🙂

[@haythamchannel3553]

Good morning David

[@DavidTipton101]

Good morning Haytham 😀

[@kilcar]

Beautiful restoration. Looks as good inside as the outside! Thanks for the video!

[@DavidTipton101]

I agree, thanks Patrick 🙂

[@PapiDoesIt]

That's a lovely set. Locating an intermittent fault is really frustrating.

[@DavidTipton101]

Agreed, thanks Papi 🙂

[@vk3crg]

David, the start of this video wasn’t silly! It was hilarious! 😂 Keep up the great work! Craig - Geelong VK3CRG

[@DavidTipton101]

Haha... thanks Craig 👍😊

[@allen-n4nn]

I hope your time away was enjoyable! Looking forward to your next adventure and stories.

[@DavidTipton101]

Thanks Allen. Back to the grind for me 🙂

[@Antony_Jenner]

Looks like a warranty job.🤣🤣 Onya mate for the video.

[@DavidTipton101]

Haha... I refused to honour my own warranty 😄 Thanks Antony.

[@Antony_Jenner]

@@DavidTipton101 🤣🤣

[@1974UTuber]

Such a lovely unit that one. I love all the big shielding cans on it. Don't worry about the intro being a bit silly Dave. We all love our crayons and my little pony colouring books.😂

[@DavidTipton101]

Thanks 1974UTuber. I feel much better now 😄

[@kennethgibbons2487]

Well really good to see you back again. Pleased that you managed to track down and fix the fault in that set - looking forward to more radio repairs now you are all refreshed.

[@DavidTipton101]

Hi Kenneth, thanks you. The radio is still going so it looks like it was the problem 🙂

[@seankearney2592]

Welcome back Dave...you were badly missed....

[@DavidTipton101]

Thanks Sean 🙂

[@glasslinger]

That is one beautiful job on the restoration!

[@DavidTipton101]

Thank you Ron 👍😀

[@Peugeot306]

Good morning David! One to watch in the coming weekend. Thx, have a nice day.

[@DavidTipton101]

Thanks Peugeot 🙂

[@Peugeot306]

@@DavidTipton101 (it’s Paul again) 👍🏻

[@kahlid-ataya]

thanks for sharing this video it's always a good way to start my day

[@DavidTipton101]

Thank you Kahlid 😀

[@navypti]

What a lovely cabinet restoration. Even the internal covers look like they've come straight out of the showroom. Looking forward to your next vid now that you're back at home base. I hope you and the family are well, and the M.I.L house sale went through ok. :)

[@DavidTipton101]

Hi Geoff, thank you. The radio was a mess when I got it but it's my favorite radio now. We are good thanks, MILs house is still up for sale unfortunately 🙂

[@nathkrupa3463]

Good work David sir i enjoyed the show thanks for sharing this video sir 👍 😊❤😊❤

[@DavidTipton101]

Thank you Nath 👍🙂

[@Graeme_Lastname]

When I was a lot younger word got around that I could fix radios. I really had no idea but time and persistence taught me a hell of a lot. Generally there was no schematic so it was seldom easy. So much easier before transistors appeared and I had to start learning again. I really miss the good access provided by the old valve sets. Thanks for the video m8, it brought back a lot of memories. 😃🖖🇦🇺

[@DavidTipton101]

Thanks Graeme. I happy you enjoyed my videos 🙂

[@Graeme_Lastname]

@@DavidTipton101 😃🖖

[@ChrisSwenson]

David ! You did it again! I was waiting until up to the very end and you didn't do it! (I'll lose more sleep)..... @ 28 seconds, you were sharing your wonderful Nella artwork with all of us, and I waited and waited to see your completed masterpiece! Just like an episode of Bullwinkle, they never ended the story. (P.S. the flower in the unicorn's mane should be mauve). You're still the best! Take Care.

[@DavidTipton101]

Hi Chris, yes, sorry about that, my Granddaughter wanted her colouring book back so I never got to finish it 😟 Mauve? damn! I was never any good at colouring in the first place. Thanks Chris 😉🙂

[@LarryDeSilva64]

Great that you use what you repair a 93 year old radio. So the 45 valve was the problem and maybe the choke intermittent possibly sometimes. Well at least it has been working fine for 6 months so you sorted out the problem. Another great troubleshooting video.

[@DavidTipton101]

Hi Larry, it looks like it was the valve with an internal short, the radio has worked perfectly since then. Thanks Larry 😊

[@billnicholson2470]

You are quite the detective David. Nice to see you back. 73 de KB7ICI.....Bill

[@DavidTipton101]

Thanks Bill 👍🙂

[@nelsonwong7048]

Great video. I loved the opening! Good job of troubleshooting

[@DavidTipton101]

Thanks Nelson 👍🙂

[@greggsvintageworkshop8974]

Great video and troubleshooting on a beautiful old set Dave!!

[@DavidTipton101]

Thanks Gregg 🙂

[@larryainsworth2975]

Always look forward to your content ❤😢

[@DavidTipton101]

Thank you Larry 🙂

[@paulperano9236]

Have you considered rewinding that bung choke ? May help with that hum.

[@DavidTipton101]

I did consider it Paul but it's potted in pitch and would be a big job. I might get up the courage one day. I don't think it is the cause of the hum though 🤔🙂

[@dogribmoon]

Great to see you survived and returned safely

[@DavidTipton101]

Thanks dogribmoon. We are home, safe and sound 🙂

[@mackfisher4487]

Dave hope you had a nice vacation, that's a handsome looking radio cabinet right out of a 1920s movies. The chassis clean design the shielding especially lends itself to a simple clean appearance. The German sets may perform better but the point-to-point wiring resembles a child's scribbling s.

[@DavidTipton101]

Thanks Mack, we had a very good vacation except for a few weeks of covid. The radio is Australian, it's my favorite 🙂

[@stephencopeland238]

What a lovely radio - I really don't know what is the best view........ Id probably have the back off with the face to the wall as your restoration is as gorgeous as the front! Thank you so very much indeed for showing and sharing

[@DavidTipton101]

Thanks Stephen, It's a lovely radio from all angles 😀

[@mikemount4411]

I very much enjoyed your video. Watching from Martin, Tennessee USA

[@DavidTipton101]

Thanks Mike in Martin, Tennessee 👍😀

[@toltec13]

I have a zenith 10s464. I noticed the polarity connection is the source of the hum, so I unplug it, rotate the plug 1/2 way, and re-plug it. The hum goes away. As far as the vacuum tube, some rectifier tubes (valves in your lingo)were notorious for shorts. I experienced this situation, and the radio smoked. Luckily, I installed a slow blow fuse in case this happened, and thank god I did. So yes, that was a bad tube. Install a fuse to save your radio from severe damage.

[@DavidTipton101]

Why not... I'll give it try. Thanks jorge 😊

[@silviowel]

saudações brasileiras ao mestre..................o mestre sempre surpreendendo com suas restaurações .................que lindo trabalho realmente um trabalho de mestre..................obrigado por doar seu conhecimento e habilidade mais uma vez obrigado do outro lado do mundo um brasileiro falando enquanto nos deixam falar..............a coisa está dificil mestre! abraços

[@DavidTipton101]

Obrigado Silvio e saudações para você no Brasil. Lamento saber das dificuldades que você está enfrentando. 😟

[@mikejohansson6711]

Crikey mate! a radio that smells bad and smokes.... hmmm.... sounds like 1 out of 3 of the ones I work on. A 45 tube wow, those are EXPENSIVE here, you could just about by a used car for what some people what for a pair of 45's. I was lucky to find about 8 at an estate sale a few years back. Great to watch you work and may God bless you!

[@DavidTipton101]

Thank you Mike. I bought the 45 from a radio club friend for $20. They are getting scarce so prices will go up, you were lucky getting 8 for, I assume, a good price👍😀

[@nzs316]

What a beauty! Your restoration is top shelf. I had to watch this twice to truly appreciate your work. So, it keeps "humming" along but, what the heck it still keeps a beat. Ok a wee bit corny but, funny nonetheless. Your colouring skills match your fine workmanship. Cheers!

[@DavidTipton101]

Thanks Neil. The colouring was my granddaughters work, I was miming 😄

[@Plons0Nard]

Once again it was a pleasure to see you tinkering again 😊 And yes, of course I remember you refurbishing this radio, a few years back. Cheers David 🤝🏻👍🏻

[@DavidTipton101]

Hi Nard, thank you 👍😊

[@ManojKumar-mx7is]

Your every video teach new thing about radios. Thanks for uploading🤗

[@DavidTipton101]

Thank you Manoj 🙂

[@stephengorin3059]

So a faulty valve after 93 years of use, geez amazing must have been built to last. I wonder if you could claim warrentee from AWA !!! That valve would have certainly had a intermittant short internally. Again a very interesting and enjoyable video david. Looking forward to your next adventure .

[@DavidTipton101]

Hello Stephen, I don't remember if I changed it in the original restoration, I'm not sure it any valves in it when I got it. Thanks Stephen 🙂

[@mrgunn2726]

Welcome back, I hope you and yours have recovered from the Covids and are rested from your travels. I did enjoy following along with you on your radio adventure, thank you for sharing.

[@DavidTipton101]

Hi Mrgunn. Thank you, yes we are rested but covid has left me somewhat weakened, the same as the first time. It will pass. Thank you 👍🙂

[@alastairbarkley6572]

Loved the Nella intro, David.

[@DavidTipton101]

Haha... thanks Alastair 😄

[@jeffreyhickman3871]

Just saw your video 📹 while looking around KZbin. Be VERY CAREFUL 🧐 while servicing these old radios 📻. Like 👍 the video 📹 depicts, too bad 👎 ya can't 😉 simply unplug it and the fire go out. Ya don't need a house 😴 fire 🔥. Your friend, Jeff.

[@DavidTipton101]

Hi Jeff. There was no smoke or fire, I pulled the plug as soon as it didn't work and I could smell something overheating 👍🙂

[@raymondmenard5444]

Hello Dave, loved this episode and i stil find it conclusive in the sense that we can sort of conclude we can never really trust our testing equipment, at least not 100% of the time. You trouble shooting this one reminded me so much about the many many hours i spend going in circles with the 87K (You know what i'm talking about...) Also it made me revisit the original series about the restoration of this beauty. I remembered just how stressed i was when you pulled the guts out, it gave me goose bumps. What an incredible restoration this one was :-)

[@DavidTipton101]

Hello Raymond, thank you. Yes the original restoration on this one was pretty in-depth. I thought it was worth the effort though. Having seen the work you put into your 87R you know how intensive working on these old sets can get. Cheers 👍😀

[@raymondmenard5444]

@@DavidTipton101 Yeah i absolutely do remember, but at the same time i'm surprised how quickly i forgot all the pain the RCA had caused me which i attribute both to the rewarding feeling we get when a set is finally done and sounding good but also to the fact that i always have something new to work on, on the bench. When you're 5 or 6 projects further down the line, you sort of forget the hardship the odd one gave you. When i saw you remove the transformer to get it rewound i suddenly remembered i had swapped mine too on the 87K. Can't believe i had forgotten about it so quickly lol

[@bigmotter001]

DT is back and in full form! I know you enjoyed the time off but your subs are giddy that you have returned to enlighten, entertain and educate us on the Tube/Valve radios of yesteryear. Question: Do I have to rename my meter from a VTVM or vacuum tube volt meter to a VVVM or vacuum valve volt meter when communicating outside the US? LOL! Thanks for all you do for us Dave and take care!

[@DavidTipton101]

Hello John. It's good to be back home and getting into some serious repairs. Hah! that's a good point 😅 We also call CRTs - CRVs... wait... I think that's a car 🤔🙂

[@hestheMaster]

A lot of work to find that you just had a bad tube. The new one didn't seem to test in the tester but you might have to look at the tube tester to see if it was working correctly which it did. So the new tube was good. That's one hell of a nice radio! Necessary to re-recheck of the work you did perform even though still hums slightly. Love "Mr. Carlson from down under". Ha-ha. Steve from Illinois

[@DavidTipton101]

Hi Steve. I did something to get the tester working for a second test, I don't remember what though. I might address the hum issue further when I have more time. Thanks Steve 👍😊

[@erikburman530]

Actually Australia has gone kind of silly. But I still love watching your channel!

[@DavidTipton101]

You might be right, thanks Erik 🙂

[@rciancia]

Very cool troubleshooting Dave. Given the early age of that radio I wonder if the filament voltage is surging on power up and weakens the filament in the tubes... older radios could absolutely do that. Excellent job as always

[@DavidTipton101]

Hi Ron. Surging filament voltage, I haven't seen that or looked for it actually. Food for thought. Thanks Ron 👍🙂

[@rciancia]

These old sets are capable of anything I have learned. Voltages are higher now then they were 90 years ago. :)

[@ralphmans]

WELCOME BACK, WE MISSED YOU!

[@DavidTipton101]

Thanks Ralph 😀

[@Digital-Dan]

Love that Essence of Allan Bradley.

[@DavidTipton101]

Haha... yes, it's quite unforgettable 😄

[@hijmestoffels5171]

I enjoyed Nella’s Adventure, so exciting. More of that please 😂!

[@DavidTipton101]

Haha.. thanks Hijme 👍😄

[@Donno308]

HI David I remember watching your original videos of this epic restoration and thinking it really set a benchmark for a high end restoration. My money is on that 45 output valve. After all, these are getting pretty old now (like me!). Lucky that you have friends in low places who could supply another one! Now you've got your coil winder, maybe you could wind a replacement choke for it. Who knows - it might improve the hum issue. By the way, I always suspected that you spent your spare time colouring in unicorns 😀 Looking forward to the next one! Cheers

[@DavidTipton101]

Hi Don. The original restore was as you said, epic. It was well worth it looking at the radio now. I have access to a good range of valves from the local radio club although this valve came from the gentleman running it. I considered rewinding the three chokes in the cardboard box, do I dare though... they are encased in pitch and would be a hell of a job. Oh... I colour lots of things not just unicorns. It annoys my granddaughter no end when I fill up her colouring books 😉😅

[@Donno308]

@@DavidTipton101 Sounds like rewinding the chokes would be a messy job but I’m sure you’ve done worse! It seems that colouring in goes with the territory. Manuel likes to colour in his schematics… One of my subscribers commented thatI have no methodology when working on radios because I don’t do that! 😂

[@DavidTipton101]

@@Donno308 Manuel would out colour me any day 😅😅

[@amaraltimimi4106]

Extant Dead keeps going. and have a nice time. all my respect to u

[@DavidTipton101]

Thank you Amaraltimimi 😊

[@willrobbinson]

very suspect tube is gassy as it still works but at times will ionize and pull high current just like a neon , lucky it didn't cause any damage ie transformer ect

[@DavidTipton101]

It appeared to have an intermittent short, it didn't look gassy I don't think. I didn't leave it on long enough to damage it thank goodness 🙂

[@JE-hm7jw]

Good Show

[@DavidTipton101]

Thanks JE 👍🙂

[@owwcam]

Welcome back Dave!

[@DavidTipton101]

Thanks owwcam 🙂

[@midnightwind8067]

Another great video. Intermittent tube. Noted. 😊

[@DavidTipton101]

Yeah... thanks Midnight 👍🙂

[@richardbrobeck2384]

Nice Dave I have General motors console from the same time as that one with huge TRF chassis a model 160b

[@DavidTipton101]

A very ornate looking radio Richard. Well done 👍😀

[@superhet7281]

Great job, Dave! I’m glad you fixed it….for a while, at least. ;-) What was wrong with your tube tester? I think the original 45 was gassy…..but who knows what was overheating and giving off an odor.

[@DavidTipton101]

Thanks Superhet. I don't remember what I did to the tester, I think it was the valve socket needed cleaning... I didn't need to open it up to make it work though. It really needs a good refurbish 🤔🙂

[@philllynch3265]

Hi Dave. Lovely radio for 1931. What's the oldest you've worked on. Hi to Karen.

[@DavidTipton101]

Hi Phill, This would be the oldest. Karen says Hi! 🙂

[@clasicradiolover]

Beautiful cabnet and a clean interior. You did an excellent job the first time. Don't you hate a fault that comes and goes?

[@DavidTipton101]

Thanks clasicradiolover. yes, I do! 😟

[@eddyaudio]

David a old warrior AWA restored with Bad Valve a 45 Valve excellent Refurbishment from the early days on your Website,Regards Ian,

[@DavidTipton101]

Thanks Ian 🙂

[@MCML50]

Hi David it is very nice to se you again, and I do remember that I saw when you did work on this radio before, and as usual god to se you thinker with it again.👍👍

[@DavidTipton101]

Hello Claes, It was a few years ago now, it is my favorite radio. Thanks 😊

[@eg9938]

great video 👍 greetings from Italy !

[@DavidTipton101]

Hello EG in Italy 🙋‍♂️ Thank you.

[@Mulletsrokkify]

I need to get some Nella and crayons when I'm ruminating over my next project or hit a snag! Reckon that could be the dogs whatzits. Nice! Excellent work as always David 👍

[@DavidTipton101]

Haha... it does the trick Mulletsrokkify 😄 Thanks.

[@craignehring]

I do wonder what was burning... Anyway great video as per usual

[@DavidTipton101]

I didn't see any sign of burnt components Craig, I was quick to kill the power when it did it. Thanks Craig 😊

[@georgeallen8860]

Hi David nice to see you back as ever i cannot wait for your next upload p.s. you are getting realy good with your camera work see you very soon hopefully

[@DavidTipton101]

Thanks George 👍🙂

[@4nk8r]

Another great video🎉 I'm wondering If a 1000uf across the transformer leads would get rid of that hum ?

[@DavidTipton101]

If I pull it out again I will give it a try, thanks Twisted1 👍🙂

[@terry5089]

@@DavidTipton101 If you put to big of a capacitor in there you can damage the #80 rectifier tube with the high current inrush at turn on. In checking the specifications I find that the maximum reservoir capacitor is 32 µF and the minimum series resistance, to limit current, is 30 Ohms. I have a 1929 Sonora TRF that I used to listen to but anymore there is nothing on AM radio worth listening to in the US.

[@DavidTipton101]

Hi Terry, thanks. I am aware of the capacitor limits for the 80 tube. I assumed he was talking about before the tube. I suspect the speaker itself is producing the hum.

[@4nk8r]

@DavidTipton101 I was just thinking it may be a ripple issue causing the hum. Can figure that out quick enough with a oscilloscope. But maybe it is the speaker. Hope you figure it our David . Cheers:)

[@janmussche6815]

Hi Dave, is a resistor together with a larger capacitor as good as a coil? To be honest I don't think so. A coil is normally very good in stabilizing a 50 or 100 Hz rimpel, reducing or even taking away the hum. You really did a fantastic job fixing that radio, it looks amazing. Something else: how large is your elektro bill? I ask that because the valve radios take a lot of power compared with transistor ones.

[@DavidTipton101]

Hello Jan. No, a choke is better but resistors and larger filter capacitors eventually replaced chokes as radio design developed. The radio is fantastic, I was very lucky to find one. The radio is a very small part of my electricity bill, I have three computers running most days, lights and fans as well. We have solar panels which cover a lot of the cost so the bill isn't too bad 🙂

[@f.k.burnham8491]

Intermittents are the worst to track down. Good job of finding the bad tube. If you changed the lead dress replacing caps, or wiring path, that could be the cause of the hum. I ran into that in an RCA console, where putting the filter caps under the chassis caused massive hum. I will leave you with these words to contemplate :"Radios hum because they don't know the words to the song".😂

[@DavidTipton101]

Agreed FJ. I kept the lead dress the same as original. The hum is present with the power output tube removed and immediately power is supplied to the set. The 80 tube has a directly heated cathode so it supplies b+ before the tubes start conducting. I suspect it is the speaker generating the hum because it is not fitted with a humbucker coil 🙂

[@artyfhartie2269]

I can see a black burnt patch on the little brown box.

[@DavidTipton101]

The chokes are packed in pitch Arty, that's bit of overflow 🙂

[@ripleysmith7583]

What a handsome radio

[@DavidTipton101]

It is... thanks ripley 🙂

[@alastairbarkley6572]

Great to see the marketing info as well. The retail price - £39 10s - if in 1931 GBP Sterling, is equivalent to about £2,700 GBP in 2024. Was that selling price in (different) Aussie pounds or did this set really sell at that eye-watering figure? My goodness, I bet there was plenty of room to haggle or discount..

[@DavidTipton101]

This was a very expensive radio and it shows in the build quality. It would have been beyond the budget of most families at the time I should think 🙂

[@SeekingTheLoveThatGodMeans7648]

Seeing the burny fault was the audio amplifier tube, perhaps the audio output transformer had overheated from the excessive plate current, and you smelled its hot insulation, but fortunately it was not hot enough to destroy the transformer. According to one RCA data sheet, its maximum plate voltage is 275 volts. It could be good to make sure it is not higher, though the 300 volts you saw was apparently with the tube out of circuit.

[@DavidTipton101]

That could be, I was lucky no other damage was done 👍🙂

[@alpcns]

Now that's what one could characterize as an odious tube.

[@DavidTipton101]

It was reprehensible alpcns. I fixed it's little red wagon though 🙂

[@billharris6886]

Hi David, that's a strange problem, and being intermittent greatly adds to the troubleshooting challenge. Anyway, I looked at your circuit and found one design error; the grid resistor on the 45 valve can't be any larger in value than 1 megohm. Using a larger value over time causes the valve to go gassy and act generally weird. The new valve will likely incur the same failure after a while. Additionally, the circuit design is running the 45 valve right at its maximum power rating, which is only useful if you only run the audio level at its maximum. According to the performance curves on the datasheet, with your B+ voltage, the bias resistor (currently at 1,500 ohms) should work better if a 3,600 ohm resistor is used. Bonuses with this value include lower audio distortion, 15 mA less plate current, longer valve life, and a cooler power transformer (about 5 watts less).

[@DavidTipton101]

Hello Bill. Thank you for taking the time to post this. I was surprised that the B+ was so high, I would have expected more like 250 Volts. The grid bias is quoted as -50V which equates to a 250V B+ as well. It has a rewound power transformer fitted which may be a reason but I'm pretty sure it's output was spot on when I fitted it. You are correct, the grid resistor maximum is 1 meg but is shown on the drawing as 2 meg. The drawing I used has been drawn using an actual radio as a guide, I wonder what values are actually fitted to my radio. I really need to revisit the radio and check everything, voltages and component values. Increasing the grid resistor would suit the higher B+ but I think it would be good to address the high B+ as well. I did find an original (I think) chart with all the voltages listed, Only the grids are referenced to ground, the rest are referenced to filaments. I tested to ground when I tested the voltages 🤔

[@billharris6886]

@@DavidTipton101 On the 45 valve datasheet, it shows 275 volts as the absolute maximum from plate to cathode. The 1.5k cathode resistor should drop about 50 volts when the valve is warmed up, subtracting from that 300 volts you are currently seeing but, this increases the chance of damaging the valve. You can easily lower the B+ by placing a 100 (more or less) ohm resistor between the rectifier and first filter capacitor. If the filament voltages are high as well, instead place a 47 ohm resistor in series with the mains input. I do the series mains resistor on all the valve radios I restore as a general rule to drop about 10 volts. Here in the US, power companies ran 110 volts at the low voltage outlets in the house, up until the 1970's and 1980's, when they increased the voltage. Today, they typically run 118 to 127 volts. So, the mains dropping resistor serves several functions; as a fuse, voltage surge limiter, and voltage dropper. I noticed your schematic shows a a hum cancelation pot that feeds the 45 valve through the 1.5k cathode resistor. However, in your video, I never saw that pot. If there is a real pot (and not two equal value resistors tied together), that could reduce your hum problem.

[@DavidTipton101]

Yes, I know the 45 is 275 max. I read somewhere It was 250 in earlier tubes and was upped later on. I had considered adding a resistor to the supply but time was short and I put it back together. There is a 260 Volt tapping on the Power transformer, I can select that and lower the input voltages. We actually lowered the domestic supply voltages in Australia from 240 to 230 Volts to align with European voltages. Unfortunately there is no pot, it's a centre tapped wire wound resistor. I'm pretty sure the hum is present with the output tube removed. If and when I pull the chassis again I will check all your suggestions 🙂

[@sheldonlatimer6688]

Good work on trouble shooting, you've done everything but disassemble the radio , now it's a wait to

[@DavidTipton101]

Thanks Sheldon 🙂

[@blitzroehre1807]

Judging from the pink/violet colour of the discharge inside the output valve it pretty much looks like it has drawn some air. That would also explain why it gets hot in the tester and the filament glow cannot be seen. Strange why the getter has not turned white at the edges.... Odd, but you solved it as usual 🙂

[@DavidTipton101]

Hi Blitz. the 45 worked some of the time and the valve didn't appear to have gone to air. It was quite puzzling... to me at least. Replacing it worked though. Thanks Blitz 🙂

[@blitzroehre1807]

@@DavidTipton101 David, maybe keep the old 45 on the mantlepiece for the next few months and watch (and film) the getter, maybe it will turn white and we all have a definite answer as to what the problem was for sure ;-) Cheers

[@DavidTipton101]

I'd have to find it first Blitz, it went into the bin 6 months ago 🙂

[@blitzroehre1807]

@@DavidTipton101 oopsie Evidence destroyed, eh?😉

[@DavidTipton101]

@@blitzroehre1807 😅

[@markallen1782]

Hi Dave I have a late 30's GE Bandmaster, with 1 shortwave band, but I can't find a restorer in Sydney that can help me. I've mostly recapped a few old 60's radios, a nearly 90 year old radio is a a big challenge, without a diagram. Any suggestions.

[@DavidTipton101]

Hi Mark, contact HRSA radio club in Sydney, they may help. If you know the model of your Bandmaster, Radiomuseum.org may have schematics. Bandmaster is a rebadged AWA so there will surely be a schematic for the AWA version 🙂 hrsa.org.au

[@thomasspilcker8382]

Can you made a old carradio with bluetooth ?

[@DavidTipton101]

There are ways it could be done but I have never attempted it 🤔

[@michaelmiller641]

That's a beautiful radio there, Dave!

[@DavidTipton101]

Thanks Michael 🙂

[@DAVIDGREGORYKERR]

Can you not get replacement tubes or what about getting some rod type tubes that have been mounted in standard vacuum tube bases.

[@DavidTipton101]

I did get a replacement tube David 👍🙂

[@8000Time]

Super !!!

[@DavidTipton101]

Thank you Valdis 👍🙂

[@sefarkas0]

It's the Vegimite pencil holder on the shelf that you smell

[@DavidTipton101]

Ahh... you might be right, good thinking Steve 😄

[@moodyga40]

i think the flux do hickey condenser is gone

[@DavidTipton101]

No, I changed that already 🤔

[@RipKirby]

So, what component produced the odor?

[@DavidTipton101]

I don't know RipKirby 🤔

[@James_Bowie]

Patience is a technician.

[@DavidTipton101]

It's a big help James 👍🙂

[@stevewalters6003]

Sometimes valves fail internally. When these radios were new, valves were the most common fault as they were probably run all day every day.

[@stevewalters6003]

Also, a shorted valve can cause excessive current through a resistor which might have caused the odour.

[@DavidTipton101]

Yes, I suspect the short was overloading something. I was able to switch it off quickly when it happened 👍🙂

[@dave1135]

Lol, David, you could put up a video of you reading a grocery list and I'd watch it

[@DavidTipton101]

Haha... that would be entertaining 😅 Thanks Dave.

[@tarstarkusz]

Isn't a purple glow a sign of air?

[@DavidTipton101]

Not nessecerally tarstarkusz.

[@ChuckKirchner-se6ib]

Spooky!! Perhaps the winning rooster has pecked it too much.

[@DavidTipton101]

Haha... that's a possibility Chuck 😄