Nice detective work with that solder blob. Just remember Dave that you have a knack for learning and explaining things in a very easy to understand method! Transistors or tubes it's just elections flowing through the components. No rocket scientists needed here to troubleshoot! Thanks for posting and take care!
Thanks John. I know the basic principle is simple but I haven't worked out the effect failed components have on other components so I can work backwards from effect to failure 🤔
Thanks Mike. Transistor sets for me are like taking a holiday, it's new and different, but it's nice to go home and the familiarity of a warm valve set 🙂
Thanks for the video. My father in-law left me an am/fm small transistor radio. After watching your video I might try to get it going. Great to see you! :-)
No one is better at making mountains out of molehills than me. The repair of the volume control including the fabrication of the boss and the spacer washer is superb. Spotting that solder blob was very sharp; it was hiding in tough area to spot. Thanks again for another excellent and informative video.
Fixing something when someone else has had a go is always a challenge. The fault no longer follows a logical path but you triumphed in the end. Looking at that circuit certainly brought back some memories. Great video as usual.
Something different in this episode and very entertaining, you applied your usual methodical approach David and solved the problem, as well as a dose of your engineering skill to sort that on/off switch and volume pot. Oh and as a bonus we got a bit of NRL and maybe some Ashes commentary thrown in!
Thanks Ken. It was nice to do something different. The pot was a challenge, it works OK but is the wrong value. I will keep an eye out for a better candidate even if I have to machine the shaft to fit. I did this about Ashes time. I didn't notice it in the video. Good find 👍🙂
You are like the Aussie version of Shango066 Dave! How many busted up non-working radios he has fixed I can't count but he always makes it as entertaining as your vids. That volume potentiometer rebuild was brilliant. Steve
UA-cam popped this video up for me this morning, I am thankful it did, I have a tiny transistor set that I fixed several months ago. It had the resistor bodge on the back of the board. It got knocked down off the shelf by one of my daughters cats and that resistor bodge came loose I was having a hell of a time trying to find where it was supposed to link up, this video gave me the road map! Thanks again, I love having coffee with Dave first thing in the morning.
My father used to try to repair small transistor radios that friends gave him. Every now and then he'd get one working again. I wish he had your channel to watch back then. It was way before youtube.
Quite a nice set for its period. I like the transformerless audio section - none of those horrible little phase splitter and output transformers which you got in most sets of this era. Coupled to that decent size loudspeaker it will have given many years of sterling service. Looks like the previous owner renewed the electrolytics and then was stumped. You did a nice job of tidying it up and the rebuild job on the volume control was a definite DT Special! You really do go where no man has gone before. It gives the rest of us courage to attempt things that seem impossible. Next weeks video - 'Brain Surgery 101'. Thanks again, Dave.
You were not " bumbleing around " You ended up fixing the radio. Good onya !!! We never stop learning. Traceing a problem in a piece of equipment that you are not certain of, can be a pain. One of the first thing one has to do is to have a good look at the problem at hand and more so if in your case the radio has been " repaired" somewere else. I was taught eyes, ears and smell, and some times touch go a long way in trying to trace a problem. But having said that over all a good job and as always look forward to you next adventure . Keep up the good work David !!
Great video! Thanks a million, I always learn something when watching your videos. One thing it reenforced for me was a bit that I learned in college. They taught us not the law, but how to find the law. Research can be the most important thing when dealing with the law, and the same thing holds true when dealing with electronics. Watching you fix that volume control was great, you showed us that instead of replacing the part, rebuild it back to it's original glory and it will serve you for another 50 years or so! Keep the great shows coming, they encourage we who dabble in radio repair to keep going. My little group of transistor radios that I have purchased right now has grown since it seems money is short for most folks so an opening bid usually wins the auction for "parts or repair" radios here in the states. I have several Westinghouse sets as I love working on their sets, they seem to be a better quality build then the junk imports.
Thanks Jerry. I'm always looking for ways to repair components, the volume pot repair worked well. Nice that yiu have a collection of radio to keep you busy 👍🙂
Nice going ! I suspect a lot of us have fallen victim to The Blob ! It shows that gently ‘prodding around’ can actually be one of the most useful fault finding techniques.
Good work David. Just a tip for you if or when you can't repair or replace a potentiometer that has an open or damaged carbon strip. I always used a lead pencil and drew several layers over the damaged area. It does work and I never had one come back faulty!
The "Tiptonian Method" of patient diagnosis and repair paid off once again for you (as always) Dave. Some forensic investigating revealed a few clues to what the problems were and eventually led to a successful outcome.😀
Holy crap ! that was tiny parts to work on. You impressed me once again Dave with that fix, but the trouble shooting part was fascinating. I downloaded the schematic and followed along and my money was on TR1 for almost the whole time. Granted i wasn't in front of the board so i could not have picked up on the solder blob, but still, you're way better than me at trouble shooting. Thank's for sharing. See yeah in the next video my friend 🙂
Hi Raymond. I struggled to work out how things were getting power, it's all back to front. I need to watch some videos. I did narrow it down in the end I guess. I couldn't see the blob till I moved that capacitor aside. It was a good learning curve though. Thanks Raymond 👍😃
@@DavidTipton101 No kidding, you figured it out very methodically, your Valve radio experience paid off for sure. Yeah we always have to watch a video or another right ? reminds me i have to educate myself on signal tracers, i think you touched on them in some of your videos, i'll have to check your playlist again. I used a small signal tracer (9v batt operated) when i got my alarm system installed, i wonder if i could use it on my radio resto projects ???
Hey Dave! Thanks for sharing this video with us! I think we all have had that moment of "Hidden Obvious Trouble" in our experiences. A friend of mine was stressing over an AA5 radio and couldn't understand why it wouldn't work. I asked him what he had done on it, looked at the schematic, and told him to replace the Cathode Resistor in the Audio Output tube. He said that there was nothing wrong with that resistor, he had measured the resistance and it was within tolerance. I told him to change it anyway. He did, and the radio started working. He couldn't understand how I could spend only 5 minutes and find the problem while he had spent days trying to get it to work. I never told him how I came to the conclusion of why that was the problem. In fact, from a physics standpoint, I might have been way off base, but I had recently had problems with a Carbon Microphone and an Elmer informed me that the carbon bits could get stuck and to make it work again to simply bang the microphone on the desk or workbench. Since that worked, I figured that it was possible that the resistor (a Carbon Composition Resistor) would measure correctly when no power was applied, but when turned on it would open up and be, in effect, a capacitor. Therefore, you would have a "resistor-capacitor across a bypass capacitor" therefore blocking the DC. Like I said before, my theory might be off, but that was what fixed the radio!
Hello David a excellent repair on Philips Radio I have serviced many of them Transistor very trouble free it was interesting finding the fault but you won eventually. I admire your persistence on Magnavox speaker I knew the people at Magnavox they were excellent people to deal with and there Loudspeakers were able to be repaired as you demonstrated against the Rola were unable to be repaired,Top Marks,Ian.
I used to work as a part time gunsmith many years ago. The boss had a sign in the shop, it read something like this: LABOR $20.00 HR - IF YOU WATCH $40.00 HR - IF YOU TRIED TO FIX IT FIRST $100.00 HR it made sense. Some home smiths can really screw up a gun, and a radio even more so. The worse case was when a fellow brings in a gun parts in a shoe box. I took one of those LEARN GUNSMITH at home courses along with working part time in the gun shop for several years, it was a work of love for me, never got paid for in shop working, I considered the education better then any pay they could have given me. I worked full time as a cop but we worked a weird schedule of 4 12 hour shifts followed by 4 days off. Since my good wife worked as well it left me a lot of spare time with little to do. I road my motorcycle a lot to kill time till I got invited to "play" in the gun shop.
Hi David hope you and the family are well. I had a similar experience with a 1939 Murphy valve radio. Initially I changed all the defective caps and reinstated the original valves (someone had fitted two separate valves instead of the original MIXER /OSC. Lots of other work as well but it worked ok. Wasn't satisfied with the audio so I changed all the resistors for modern types after which it would not function at all! Put it back in the frame and after much investigation a large blob of solder fell out of the wavechange switch (a large open contact affair). The radio then functioned perfectly with much better audio. Silly me! Best wishes Lynton G4XCQ
Dave, you're coming along nicely on your transistor learning curve! The most important thing I was taught by an old school engineer was to pay attention to the the base emitter junction. The different potential between these two junctions should be .2v for germanium and .6 or .7 for silicon transistors. Great find on the shorted diode...............
In this case 0.1 Volt. Thanks John. That is exactly the information I need to learn. The information is there , I haven't bothered to look it up yet. Cheers 👍🙂
The ones that someone has had a go at before you are always the trickiest. You have to look for things that would never normally be there. Another great video. I really liked the volume pot rebuild, seems a shame to replace it after all that effort. Still, hope you get one for it. It's a nice little radio.
Thanks @radio-ged4626. I checked out the previous repairs first and everything was in order. I haven't had any pots turn up, I will add a resistor to approximate the 2 K requited and leave it fitted. It work perfectly as it is, the resistor will keep the radio as intended 🙂
Hi David. You started off your video saying; "I only paid a few bucks for it..." and yet for those few bucks you've got a forever reminder Solder Blob, a valuable learning surgery on a volume pot, an AA5 fellow Radio guy's suggested trick tried out successfully, and the fun of returning the radio to working again. Maybe you could get a cheap magnifying glass at the dollar store and make a display of it over your Solder Blob (?) Thanks for another fine video! -Chris P.S....my vote is on a prior repairer leaving the blob.
Hi Chris. I bought the radio as a learning tool and like you say, it paid off. Haha... I like the idea of the blob mounted next the the radio on display 👍😀 Thanks Chris.
As always, great detective work Dave, and well explained. I have a possible sighting of the solder blob at 5:00 or so - so looks like it was from the previous repair attempt... . Anyways, great video - looking forward to your next instalment!
Amazing.... I would have said right off the bat, those AF11x transistors "tin whisker" would be the problem. You must have the only working examples known to humankind! Mullard "mustard" caps - you can rely on them to work, just as assuredly as you can rely on the sun to come up in the morning. Well done with the volume pot.... I personally have never had any success with rebuilding them, though others, including yourself, seem to be able to make it work. Nice job, and nice to have some AM stations to listen to, once you have it working again.
Me too @whitesapphire5865. Haha... they might be the last ones. The one I fitted in the end had been zapped some years ago and was still working. I refitted the mustard caps, I knew they would be OK. The volume pot worked alright, luckily the replacement resistance strip was almost identical 🙂
Wow, that was an adventure Dave..Great work, info and ultimate fix..Great to see the process..Nice little gem resurrected..Thanks for sharing..Ed..uk..😀
Greetings from Canada. Great to see you again, I look forward to all your videos Dave. Lately, I've been binge-watching your collection. During the COVID-19 epidemic, I was in and out of the hospital getting bits and pieces repaired and replaced ( what else are you gonna do during an epidemic lol), so I guess I missed a few or I don't remember them. Stay well and healthy and nice job on the radio.
Hello Mark in Canada, thank you. I hope you are running on all cylinders now. We people seem to get a run of health issues, well I do, then everything works properly for a while. Thanks Mark, take care 👍🙂
Hi Dave, If I, whilst working as a service tech, had a pound for each time I ploughed into a repair without doing a basic check before hand, I would easily have amassed a minimum of £250. No matter how much we promise ourselves we’ll be more vigilant next time, it keeps on happening to all of us my friend. I guess we are too eager to, “Get stuck in” LOL! Another enjoyable repair video my friend. Best regards, Phil.
Thanks Phil. I did check the replaced components where correctly installed and the soldering wasn't shorted. But the way I had the board facing I couldn't see the blob, that's not an excuse but it stopped me seeing it a bit earlier on. I will try to be more vigilant in future but, yes, we are too eager sometimes. Take care Phil 🙂
Great repair, like you, I am much more familiar with valve sets, but any set that has been got at before needs close scrutiny. I reckon that solder blob was left by the previous owner, excellent job on the volume pot, these can be a real challenge!
Es una radio muy bella y tú has encontrado la avería muy fácilmente. Felicidades por el trabajo y también por tener esa preciosa radio. Gracias por compartir conocimientos. Saludos,
I only worked on a couple transistor radios one small one big the zenith 1000 transoceanic had older resisters but was able to get that one working on all bands. Glad to see I'm not the only who sees transistor radios as a challenge. I k we you could fix this one because you are always great at troubleshooting. Thanks for another informative video.
Good work Dave. Those AF11x transistors are quite often the cause of a dead radio from that era (although not in this case with that solder short of course!). I've often found that even when they show up OK on the tester they still don't work properly. I think an hfe of 11 would indicate it's quite poor. I've had some success replacing them with modern silicon PNPs but that doesn't always work for the osc/mixer stage.
Thank you Neil. Yes, I expected it would be the transistor with their reputation. !!hFE is way too low, I didn't know that at the time. I learnt a lot on this project. I will replace them with the AF12XX series in future if I can get them 👍🙂
G,day David, I glad you found" bit of Solder" you are good trouble shooter. You are fine on little details, years knowing what doing in the circuit. Hope your health is getting better mate? Cheers thanks again for fantastic video.
Great job David sir transistor substitute available on amplifier stage AC 127 substitute c188 and AC 128 substitute c187 I think you know but my knowledge sharing you sir. thanks for sharing this video sir
Dave, I use a trick when checking small signal transistors with an ohmmeter. in addition to check for two diodes from the base for forward and reverse action like you did. i put the ohmmeter across the collector emitter and check there is no current but then put my finger across the base collector pins. if the transistor is working you should see current flow as it becomes forward biased.
Well done. TR1 looked to be leaking base collector in reverse (0.4V 5:40) and, as you say, hFE should be at least 50 so wondered whether you fitted a direct replacement post blob removal (jackup resistor removed). Looking at the state of the tuning cap, I doubt you were responsible for the blob. Looks like atkelar has some competition, ho, ho.
Thank you Ralph. Yes, I thought that too. I fitted another AF116 from another set which at this stage at least is working. The blob has been spotted earlier in the video be an eagle eyed viewer 🙂
Well done David (as per usual) - that solder lump really got you. Transistor circuit boards are always a pain so much circuitry on such a small space coupled with ham-fisted soldering skills can produce all sorts of undesirable effects... neat work on the other things you repaired/sorted🙂
That soldering looked rough as guts when you got it. Glad you got it tidied up and running again. I laughed when I saw that hfe value. Years ago I threw out my childhood box of old circuit boards that would have been filled with geranium transistors and diodes. I obviously regret doing that now!! I see you have a bot/spammer in the comments. Shango has a couple haha. Must mean your channel is moving up in the world.
Yeah, it was low alright. I learned something at least 🙂 Pity about the ditched transistors, if only we knew these things at the time. I don't know what the spammer was about, I regrettably blocked it, 15 to 20 comments per video is too much ☹️
A very good resto as usual David. And now I hav some news, I hav bought an old radio which was made her in my home town of Stockholm Sweden in 1956-57 and it is renovated with new stuff inside and with a new magic eye. It is called Tjerneld Turkos and I like it, but I am sorry to say that we have lost a lot of radiostations her in Sweden, I think you hav moor stations in Australia. 👍
Mr. Blobby strikes again, at least you were spared the depredations of the phantom twiddler. Unless it's a real shelf Queen, I've taken to replacing the unreliable AF11Xs (even after zapping) with BC558Cs, works most times. The pot transplant was superb.
Agreed, the radio settings hadn't been touched luckily. I will have to learn how to bias replacement silicon transistors in germanium sets. The BC558s etc are readily available. Thanks Steven 🙂
Thanks again Dave. I don't know much about transistors but I guess I'm going to have a crack at one sooner or later. Can't let Manuel and Graham have them all, can I? At least from this video I worked out how a transistor oscillator works. Cheers
Hi Don, Thanks. I don't know much either and was starting to wonder if I would find the problem with this one. I follow Manuel and Graham closely when they work on transistor sets, I have picked up a lot from them. I look forward to the day you try doing one 👍😃
You can also pull up another working radio next to the inoperative radio , turn both “On” tune the working radio if the Oscillator is not working it will start playing using the working radios oscillator . Quick check .
HI David, Hope you are keeping well and that was a neat bit of detective work as well as skilled work on that pot. Amazingly low hfe on that transistor! Excellent video too, really enjoyed watching it. Gerry
Hi Gerry, thank you. I had no clue as to what the hFE should be till I looked it up. That transistor still worked in the second radio I cannibalised the replacement transistor from 🤷♂️
Thanks Peter. I don't remember how I machinded it. I made it from a flat sheet. I probably screwed it onto a piece of dowel mounted in the chuck and machined it that way 🤔
Old radio techs used to rebuild the worn carbon tracks with a very soft graphite pencil. Graphite will lubricate the wiper and because it's also conductive it'll help fill in the gaps and stop that crackle. All they did was "draw" the track with the pencil - anything from 2 - 6B should do.
Hi Ian. I could have used it but I knew the oscillator wasn't running and the transistor voltages were all wrong. I should have dragged it out to prove it 👍🙂
pnp silicon like 2n3906 is worth a try along with higher bias voltage. Beta for 10 is too low. check the other af117 also, may have very low beta too. 10k pot is about right. 2k is too low.
How are you liking your Brymen BM768? I have 3 Brymen meters, BM-869s, 235 and 525. Love them all. The 869s is very comparable to my venerable Fluke 189. What I love about the Brymen meters is they remember at the next power up where you had it set at last power down. Fluke and every other meter company goes back to factory settings at next power up. Great video as always David. Our favorite island radio genius Manuel digs Brymen meters too.
Hi @SIXSTRING63. The Bryman meter is great, I like how it can read AC and DC at once, that was the main reason for buying it. Yep, Manuel has a couple as well, can't get a better recommendation than that 😃 Thanks @SIXSTRING63.
foiled by the old dreaded solder blob! haha......look at you Mr. Tipton.... fabricating one good volume control from two.......The only thing missing from this video is "Dave Cinema" I rate this video 4🍺🍺🍺🍺
It's the second time this week I've been fooled by the blob Buzz 😄 I don't have any Dave Cinema Buzz. I have videos of the kids and my wedding but nothing like your efforts. I'll be content watching yours 😄 Thanks Buzz 👍🙂
That volume refit was excellent, Once again Dave has gone above and beyond. Thanks for the vid mate!
Thanks Antony 😃
@DavidTipton101
Nice detective work with that solder blob. Just remember Dave that you have a knack for learning and explaining things in a very easy to understand method! Transistors or tubes it's just elections flowing through the components. No rocket scientists needed here to troubleshoot! Thanks for posting and take care!
Thanks John. I know the basic principle is simple but I haven't worked out the effect failed components have on other components so I can work backwards from effect to failure 🤔
@@DavidTipton101 I'm always working backwards from my failures 🤣
I never figured the trouble shooting out. I'm still trying to learn. I'm probably never going to, but I enjoy watching you.
I hope to figure it out too one day @clasicradiolover 👍🙂
Great switch mod. Nice to see you having a break from the old valves 😄 Thanks Dave
Thanks Mike. Transistor sets for me are like taking a holiday, it's new and different, but it's nice to go home and the familiarity of a warm valve set 🙂
Hi Dave , great stuff. Many thanks for another lesson in radio trouble shooting. From Nr Liverpool UK.
Thank you Chris, my pleasure 🙂
_Will, knowledge, sense of precision and persistence led you to perfection in electronics. Best regards from_ ❤
Thank you Domenico 😃
Thanks for the video. My father in-law left me an am/fm small transistor radio. After watching your video I might try to get it going. Great to see you! :-)
Thanks @batman387. Why not have a go at the radio 🙂
Hats off to you, Sir, for that volume control repair, and some great detective work as usual :)
Thank you for watching Edward, the volume control repair was a fun one. 🙂
No one is better at making mountains out of molehills than me. The repair of the volume control including the fabrication of the boss and the spacer washer is superb. Spotting that solder blob was very sharp; it was hiding in tough area to spot. Thanks again for another excellent and informative video.
Thank you Jeff. I had the circuit board facing so I couldn't see the blob, I could have saved some time if had just rotated it 180 degrees 😄
David, I am glad to be back (have been on the workbench myself with a cardio issue) and to see you in action ....I knew you would sort it out!!!
Fixing something when someone else has had a go is always a challenge. The fault no longer follows a logical path but you triumphed in the end. Looking at that circuit certainly brought back some memories. Great video as usual.
Thanks Ian. Agreed, you now have the original fault plus anything else done by the last guy 🙄🙂
Something different in this episode and very entertaining, you applied your usual methodical approach David and solved the problem, as well as a dose of your engineering skill to sort that on/off switch and volume pot. Oh and as a bonus we got a bit of NRL and maybe some Ashes commentary thrown in!
Thanks Ken. It was nice to do something different. The pot was a challenge, it works OK but is the wrong value. I will keep an eye out for a better candidate even if I have to machine the shaft to fit. I did this about Ashes time. I didn't notice it in the video. Good find 👍🙂
You are like the Aussie version of Shango066 Dave! How many busted up non-working radios he has fixed I can't count
but he always makes it as entertaining as your vids. That volume potentiometer rebuild was brilliant. Steve
Hi Steve, thanks. Shango is way ahead of me but thanks. The pot worked out well 😃
UA-cam popped this video up for me this morning, I am thankful it did, I have a tiny transistor set that I fixed several months ago. It had the resistor bodge on the back of the board. It got knocked down off the shelf by one of my daughters cats and that resistor bodge came loose I was having a hell of a time trying to find where it was supposed to link up, this video gave me the road map! Thanks again, I love having coffee with Dave first thing in the morning.
Glad it helped Jerry. Enjoy your coffee ☕🙂
My father used to try to repair small transistor radios that friends gave him. Every now and then he'd get one working again. I wish he had your channel to watch back then. It was way before youtube.
I would have been lost without UA-cam and the internet. There is so much information out there. Thanks @drstrangelove09 🙂
Awesome fix which took a lot of patience. I commend your determination in bringing this gem back to life.
Thanks Michael 😀
Quite a nice set for its period. I like the transformerless audio section - none of those horrible little phase splitter and output transformers which you got in most sets of this era. Coupled to that decent size loudspeaker it will have given many years of sterling service.
Looks like the previous owner renewed the electrolytics and then was stumped. You did a nice job of tidying it up and the rebuild job on the volume control was a definite DT Special! You really do go where no man has gone before. It gives the rest of us courage to attempt things that seem impossible. Next weeks video - 'Brain Surgery 101'.
Thanks again, Dave.
Thanks @EuroScot2023. It is a nice radio and performs well for its size . I was willing to try brain surgery but it's so damn hard to get volunteers👍🙂
...a DOWNSIDE of "transformerless" amplifier stages, is that they are EASY to blow out: I found that out the HARD way...
Another great job. I really enjoy your videos. Thank you so much. 🙂
Thank you Jan, my pleasure 😃
Damn them newfangled solid state units. Nice job repairing the potentiometer. Take care & thanks for the video!
Thanks James 😃
Philips , rádio da melhor qualidade !
Thanks Jose 👍🙂
You were not " bumbleing around " You ended up fixing the radio. Good onya !!! We never stop learning. Traceing a problem in a piece of equipment that you are not certain of, can be a pain. One of the first thing one has to do is to have a good look at the problem at hand and more so if in your case the radio has been " repaired" somewere else. I was taught eyes, ears and smell, and some times touch go a long way in trying to trace a problem. But having said that over all a good job and as always look forward to you next adventure . Keep up the good work David !!
Thanks Stephen. I did get there in the end and picked up a few tips on the way. The next one will be easier with what I learned from this project 🙂
It was great to watch and listen your explanations both. Thanks for the pleasure! Also I very like the exterior design of early 1960-ies.
Thank you Igor 👍
Great video! Thanks a million, I always learn something when watching your videos. One thing it reenforced for me was a bit that I learned in college. They taught us not the law, but how to find the law. Research can be the most important thing when dealing with the law, and the same thing holds true when dealing with electronics. Watching you fix that volume control was great, you showed us that instead of replacing the part, rebuild it back to it's original glory and it will serve you for another 50 years or so! Keep the great shows coming, they encourage we who dabble in radio repair to keep going. My little group of transistor radios that I have purchased right now has grown since it seems money is short for most folks so an opening bid usually wins the auction for "parts or repair" radios here in the states. I have several Westinghouse sets as I love working on their sets, they seem to be a better quality build then the junk imports.
Thanks Jerry. I'm always looking for ways to repair components, the volume pot repair worked well. Nice that yiu have a collection of radio to keep you busy 👍🙂
Nice going ! I suspect a lot of us have fallen victim to The Blob ! It shows that gently ‘prodding around’ can actually be one of the most useful fault finding techniques.
Thank you @sinewave4236. I should have done more prodding earlier 🙄🙂
Great to see this set brought back to life
Your valiant efforts pay off !!
As always a nice video production and repair
Thank you Craig 👍🙂
...persistence pays off..
Good work David. Just a tip for you if or when you can't repair or replace a potentiometer that has an open or damaged carbon strip. I always used a lead pencil and drew several layers over the damaged area. It does work and I never had one come back faulty!
Thank you Roger, I'll keep that in mind 👍🙂
Hi David. I love the old valve radios repairs , but the tranies bring back the sixties nostalgia of music, and my youth, long gone LOL. Hi to Karen
Yes, I remember those days as well. Most homes had a transistor radio on the kitchen table back then. Karen says HI!😃
Marvelous job getting that oscillation!
Thank you Keith 🙂
Scrubbed up well, a bit of microsurgery and it sounds well! Lovely job as always.
Thank you Paul 👍🙂
I love these old transistor radios.. They're almost like magic.
It was magic that I was able to make it work with my limited knowledge 😄 Thanks Dan.
Really great troubleshooting Dave, glad it was just the solder blob. Great repairs on the potentiometer too!
Hi Gregg. Thank you 👍🙂
The "Tiptonian Method" of patient diagnosis and repair paid off once again for you (as always) Dave. Some forensic investigating revealed a few clues to what the problems were and eventually led to a successful outcome.😀
I took the long way round but got there in the end. Thanks @RoughJustice2k18 👍😀
Holy crap ! that was tiny parts to work on. You impressed me once again Dave with that fix, but the trouble shooting part was fascinating. I downloaded the schematic and followed along and my money was on TR1 for almost the whole time. Granted i wasn't in front of the board so i could not have picked up on the solder blob, but still, you're way better than me at trouble shooting. Thank's for sharing. See yeah in the next video my friend 🙂
Hi Raymond. I struggled to work out how things were getting power, it's all back to front. I need to watch some videos. I did narrow it down in the end I guess. I couldn't see the blob till I moved that capacitor aside. It was a good learning curve though. Thanks Raymond 👍😃
@@DavidTipton101 No kidding, you figured it out very methodically, your Valve radio experience paid off for sure. Yeah we always have to watch a video or another right ? reminds me i have to educate myself on signal tracers, i think you touched on them in some of your videos, i'll have to check your playlist again. I used a small signal tracer (9v batt operated) when i got my alarm system installed, i wonder if i could use it on my radio resto projects ???
@@raymondmenard5444 There is a link under my videos to the signal tracer I use. It has been very handy for fault tracing.
...SKILL is certainly important- but LUCK has a lot to do with it too...
@@DavidTipton101...well, "we live and learn"!!!
Hey Dave!
Thanks for sharing this video with us! I think we all have had that moment of "Hidden Obvious Trouble" in our experiences. A friend of mine was stressing over an AA5 radio and couldn't understand why it wouldn't work. I asked him what he had done on it, looked at the schematic, and told him to replace the Cathode Resistor in the Audio Output tube. He said that there was nothing wrong with that resistor, he had measured the resistance and it was within tolerance. I told him to change it anyway. He did, and the radio started working. He couldn't understand how I could spend only 5 minutes and find the problem while he had spent days trying to get it to work. I never told him how I came to the conclusion of why that was the problem. In fact, from a physics standpoint, I might have been way off base, but I had recently had problems with a Carbon Microphone and an Elmer informed me that the carbon bits could get stuck and to make it work again to simply bang the microphone on the desk or workbench. Since that worked, I figured that it was possible that the resistor (a Carbon Composition Resistor) would measure correctly when no power was applied, but when turned on it would open up and be, in effect, a capacitor. Therefore, you would have a "resistor-capacitor across a bypass capacitor" therefore blocking the DC. Like I said before, my theory might be off, but that was what fixed the radio!
Interesting Wayne, I'll keep that in the memory banks. Thanks 👍😃
Hello David a excellent repair on Philips Radio I have serviced many of them Transistor very trouble free it was interesting finding the fault but you won eventually.
I admire your persistence on Magnavox speaker I knew the people at Magnavox they were excellent people to deal with and there Loudspeakers were able to be repaired as you demonstrated against the Rola were unable to be repaired,Top Marks,Ian.
Hi Ian, thank you. I was surprised when the voice coil was exposed with the magnet removed. That made it very easy 👍🙂
Glory be to God, today I remembered your channel. Thank God that you are fine. I wish you all the best🙂🙂
Thank you @seddas6383. All the best to you 🙂
I used to work as a part time gunsmith many years ago. The boss had a sign in the shop, it read something like this: LABOR $20.00 HR - IF YOU WATCH $40.00 HR - IF YOU TRIED TO FIX IT FIRST $100.00 HR it made sense. Some home smiths can really screw up a gun, and a radio even more so. The worse case was when a fellow brings in a gun parts in a shoe box. I took one of those LEARN GUNSMITH at home courses along with working part time in the gun shop for several years, it was a work of love for me, never got paid for in shop working, I considered the education better then any pay they could have given me. I worked full time as a cop but we worked a weird schedule of 4 12 hour shifts followed by 4 days off. Since my good wife worked as well it left me a lot of spare time with little to do. I road my motorcycle a lot to kill time till I got invited to "play" in the gun shop.
Haha... that was a good sign to have 😄
Thanks Dave! Nice change this time but I'm looking forward to the next valve set, and please more case restoration!!!
Thanks @owwcam. You're in luck. My next series is a timber cabinet 👍😃
Hi David hope you and the family are well.
I had a similar experience with a 1939 Murphy valve radio. Initially I changed all the defective caps and reinstated the original valves (someone had fitted two separate valves instead of the original MIXER /OSC. Lots of other work as well but it worked ok. Wasn't satisfied with the audio so I changed all the resistors for modern types after which it would not function at all! Put it back in the frame and after much investigation a large blob of solder fell out of the wavechange switch (a large open contact affair). The radio then functioned perfectly with much better audio. Silly me!
Best wishes
Lynton G4XCQ
Haha... that sounds normal Lynton, simple mistakes set us back so much. The name of the radio should have given you a heads up 😄 Thanks Lynton.
Dave, you're coming along nicely on your transistor learning curve! The most important thing I was taught by an old school engineer was to pay attention to the the base emitter junction. The different potential between these two junctions should be .2v for germanium and .6 or .7 for silicon transistors. Great find on the shorted diode...............
In this case 0.1 Volt. Thanks John. That is exactly the information I need to learn. The information is there , I haven't bothered to look it up yet. Cheers 👍🙂
Thank you very much for another video! You can take a lot for yourself. Hello from Israel! Thanks again!
Thank you Vladimir in Israel, I will 👍😃
Excellent work Sir!
Watching here from the Philippine Islands...
Thank you Manuel in the Philippines 🌴😃
The ones that someone has had a go at before you are always the trickiest. You have to look for things that would never normally be there. Another great video. I really liked the volume pot rebuild, seems a shame to replace it after all that effort. Still, hope you get one for it. It's a nice little radio.
Thanks @radio-ged4626. I checked out the previous repairs first and everything was in order. I haven't had any pots turn up, I will add a resistor to approximate the 2 K requited and leave it fitted. It work perfectly as it is, the resistor will keep the radio as intended 🙂
Hi David. You started off your video saying; "I only paid a few bucks for it..." and yet for those few bucks you've got a forever reminder Solder Blob, a valuable learning surgery on a volume pot, an AA5 fellow Radio guy's suggested trick tried out successfully, and the fun of returning the radio to working again. Maybe you could get a cheap magnifying glass at the dollar store and make a display of it over your Solder Blob (?) Thanks for another fine video! -Chris P.S....my vote is on a prior repairer leaving the blob.
Hi Chris. I bought the radio as a learning tool and like you say, it paid off. Haha... I like the idea of the blob mounted next the the radio on display 👍😀 Thanks Chris.
As always, great detective work Dave, and well explained. I have a possible sighting of the solder blob at 5:00 or so - so looks like it was from the previous repair attempt... . Anyways, great video - looking forward to your next instalment!
Hey yeah! I think you're right! I looked through footage trying to see it but failed. Good work Emma 😃 Thank you.
Thanks for the video. Made my Friday 😊
Thanks Manuel. I hope you didn't harm yourself laughing at my efforts 🤣
@@DavidTipton101 : Nope, I never laugh at others. Only at myself 😊
I don't think I would have the patience to machine something that small, nice one Dave.
It only takes a few minutes, no biggie. Thanks Bob 👍🙂
Well done.. All American Five aka Rick McWorter is amazing at this stuff... I have learned so much from him.... and now from you :) Great job mate
Hi Ron. I agree, I have watched many of his videos and he explains things very well. Thanks Ron 👍😀
Amazing.... I would have said right off the bat, those AF11x transistors "tin whisker" would be the problem. You must have the only working examples known to humankind!
Mullard "mustard" caps - you can rely on them to work, just as assuredly as you can rely on the sun to come up in the morning.
Well done with the volume pot.... I personally have never had any success with rebuilding them, though others, including yourself, seem to be able to make it work. Nice job, and nice to have some AM stations to listen to, once you have it working again.
Me too @whitesapphire5865. Haha... they might be the last ones. The one I fitted in the end had been zapped some years ago and was still working. I refitted the mustard caps, I knew they would be OK. The volume pot worked alright, luckily the replacement resistance strip was almost identical 🙂
well done again David , as ever i always look forward to your video's
Thank you George 👍😃
Repairing a potentiometer, that's my style. David you've done it great!
👍👍👍👍👍
Thank you Bernd 😃
Wow, that was an adventure Dave..Great work, info and ultimate fix..Great to see the process..Nice little gem resurrected..Thanks for sharing..Ed..uk..😀
Thanks Ed 👍😃
Greetings from Canada. Great to see you again, I look forward to all your videos Dave. Lately, I've been binge-watching your collection. During the COVID-19 epidemic, I was in and out of the hospital getting bits and pieces repaired and replaced ( what else are you gonna do during an epidemic lol), so I guess I missed a few or I don't remember them. Stay well and healthy and nice job on the radio.
Hello Mark in Canada, thank you. I hope you are running on all cylinders now. We people seem to get a run of health issues, well I do, then everything works properly for a while. Thanks Mark, take care 👍🙂
That's a handsome little radio. Nice job!
Thanks Papi 🙂
Hi Dave,
If I, whilst working as a service tech, had a pound for each time I ploughed into a repair without doing a basic check before hand, I would easily have amassed a minimum of £250. No matter how much we promise ourselves we’ll be more vigilant next time, it keeps on happening to all of us my friend. I guess we are too eager to, “Get stuck in” LOL!
Another enjoyable repair video my friend.
Best regards, Phil.
Thanks Phil. I did check the replaced components where correctly installed and the soldering wasn't shorted. But the way I had the board facing I couldn't see the blob, that's not an excuse but it stopped me seeing it a bit earlier on. I will try to be more vigilant in future but, yes, we are too eager sometimes. Take care Phil 🙂
Great repair, like you, I am much more familiar with valve sets, but any set that has been got at before needs close scrutiny.
I reckon that solder blob was left by the previous owner, excellent job on the volume pot, these can be a real challenge!
Thanks Mark. Someone picked up a shot of the blob in the video at the 5:00 mark 🙂
😅great work in finding the cause of why there was no sound , I learn a lot from watching you solve the problem
Thank you Sheldon 👍😃
Es una radio muy bella y tú has encontrado la avería muy fácilmente. Felicidades por el trabajo y también por tener esa preciosa radio. Gracias por compartir conocimientos. Saludos,
Saludos Kresve, gracias 🙂
I only worked on a couple transistor radios one small one big the zenith 1000 transoceanic had older resisters but was able to get that one working on all bands. Glad to see I'm not the only who sees transistor radios as a challenge. I k we you could fix this one because you are always great at troubleshooting. Thanks for another informative video.
Hi Larry, thank you. I need to study some transistor theory, save myself some time 👍😃
Good work Dave. Those AF11x transistors are quite often the cause of a dead radio from that era (although not in this case with that solder short of course!). I've often found that even when they show up OK on the tester they still don't work properly. I think an hfe of 11 would indicate it's quite poor. I've had some success replacing them with modern silicon PNPs but that doesn't always work for the osc/mixer stage.
Thank you Neil. Yes, I expected it would be the transistor with their reputation. !!hFE is way too low, I didn't know that at the time. I learnt a lot on this project. I will replace them with the AF12XX series in future if I can get them 👍🙂
Amazing what 3 transistors can do and so efficient . Thankyou for sharing your great radio adventures on a Friday night :)
It's 6 transistors! LoL
Hi Loe, thank you. Transistors are so much better than valves, size and efficiency wise 😃
@@EuroScot2023 oops
G,day David, I glad you found" bit of Solder" you are good trouble shooter. You are fine on little details, years knowing what doing in the circuit. Hope your health is getting better mate? Cheers thanks again for fantastic video.
Thank you Dennis. I'm well thank you 😃
Thumbs up Dave!
Thank you paul 👍🙂
Great job David sir transistor substitute available on amplifier stage AC 127 substitute c188 and AC 128 substitute c187 I think you know but my knowledge sharing you sir.
thanks for sharing this video sir
Thank you Nath. Thanks for the substitution info. I will need to check the bias if I go to silicon 👍🙂
Dave, I use a trick when checking small signal transistors with an ohmmeter. in addition to check for two diodes from the base for forward and reverse action like you did. i put the ohmmeter across the collector emitter and check there is no current but then put my finger across the base collector pins. if the transistor is working you should see current flow as it becomes forward biased.
That's gold Steve. I will try it on a spare transistor, thanks 👍😃
@@DavidTipton101 if it’s a power transistor or low gain, you may have to lower the resistance of you finger by giving it a little lick!
Great work David 👏
Thank you Haytham 🙂
I like your potentiometer fix!
Thanks Fred 👍😀
Well done. TR1 looked to be leaking base collector in reverse (0.4V 5:40) and, as you say, hFE should be at least 50 so wondered whether you fitted a direct replacement post blob removal (jackup resistor removed). Looking at the state of the tuning cap, I doubt you were responsible for the blob. Looks like atkelar has some competition, ho, ho.
Thank you Ralph. Yes, I thought that too. I fitted another AF116 from another set which at this stage at least is working. The blob has been spotted earlier in the video be an eagle eyed viewer 🙂
Well done David (as per usual) - that solder lump really got you. Transistor circuit boards are always a pain so much circuitry on such a small space coupled with ham-fisted soldering skills can produce all sorts of undesirable effects... neat work on the other things you repaired/sorted🙂
Hi Kenneth, thank you. Yeah, I couldn't see it from the way I had it facing. Live and learn 😄
Very nice and informative video. Thanks for sharing.
Thanks Sathiya 🙂
You're a better man than I am Dave!
Haha... thanks John 😄
I've never seen a potentiometer transplant before. Amazing.
Hi @misterhat5823. Long time no hear. Thank you 🙂
That soldering looked rough as guts when you got it. Glad you got it tidied up and running again. I laughed when I saw that hfe value. Years ago I threw out my childhood box of old circuit boards that would have been filled with geranium transistors and diodes. I obviously regret doing that now!! I see you have a bot/spammer in the comments. Shango has a couple haha. Must mean your channel is moving up in the world.
Yeah, it was low alright. I learned something at least 🙂 Pity about the ditched transistors, if only we knew these things at the time. I don't know what the spammer was about, I regrettably blocked it, 15 to 20 comments per video is too much ☹️
You see spammers, report them (3 dots on the right); pick appropriate selection. If Google can censor, so can we.
A very good resto as usual David. And now I hav some news, I hav bought an old radio which was made her in my home town of Stockholm Sweden in 1956-57 and it is renovated with new stuff inside and with a new magic eye. It is called Tjerneld Turkos and I like it, but I am sorry to say that we have lost a lot of radiostations her in Sweden, I think you hav moor stations in Australia. 👍
Thank you Claes. Nice to get a Swedish radio Claes. We still have a good amount of AM radio stations, I believe Europe is closing them down ☹️
nice to see your video again. really nice work Dave 👍
Thank you @amaraltimimi4106 🙂
Mr. Blobby strikes again, at least you were spared the depredations of the phantom twiddler. Unless it's a real shelf Queen, I've taken to replacing the unreliable AF11Xs (even after zapping) with BC558Cs, works most times. The pot transplant was superb.
Agreed, the radio settings hadn't been touched luckily. I will have to learn how to bias replacement silicon transistors in germanium sets. The BC558s etc are readily available. Thanks Steven 🙂
Good job David I still us my Philips radio every day the same as the one you repaired
Hi Andy, thanks. Philips made good stuff back in the day, a little left field sometimes but generally good 😃
Thanks again Dave. I don't know much about transistors but I guess I'm going to have a crack at one sooner or later. Can't let Manuel and Graham have them all, can I?
At least from this video I worked out how a transistor oscillator works.
Cheers
Hi Don, Thanks. I don't know much either and was starting to wonder if I would find the problem with this one. I follow Manuel and Graham closely when they work on transistor sets, I have picked up a lot from them. I look forward to the day you try doing one 👍😃
You can also pull up another working radio next to the inoperative radio , turn both “On” tune the working radio if the Oscillator is not working it will start playing using the working radios oscillator . Quick check .
Hi Keith, thanks. I have used two radio to check the oscillator before. I only listen for the feedback, I haven't tried to tune a station 👍🙂
Love the repair on the pot excellent video.
Thank you Rob 🙂
HI David, Hope you are keeping well and that was a neat bit of detective work as well as skilled work on that pot. Amazingly low hfe on that transistor! Excellent video too, really enjoyed watching it. Gerry
Hi Gerry, thank you. I had no clue as to what the hFE should be till I looked it up. That transistor still worked in the second radio I cannibalised the replacement transistor from 🤷♂️
Great video Dave. Pot rebuild was a master stroke. Would love to have seen a few secs footage of the parts machining in progress.
Thanks Peter. I don't remember how I machinded it. I made it from a flat sheet. I probably screwed it onto a piece of dowel mounted in the chuck and machined it that way 🤔
Old radio techs used to rebuild the worn carbon tracks with a very soft graphite pencil. Graphite will lubricate the wiper and because it's also conductive it'll help fill in the gaps and stop that crackle. All they did was "draw" the track with the pencil - anything from 2 - 6B should do.
Thanks LLoyd. I didn't think to do that, a fair bit of the track was totally missing so... but a good idea for crackly pots. Thanks 👍🙂
@@DavidTipton101 And that David, is why you can buy conductive silver loaded paint ;)
A nice little repair Dave!
Thank you Colin 🙂
9:00 The Oscillator's not running? Its legs were chopped off! Ouch! LOL
🙂
Great work with that potentiometer. How'd you machine that plug--was that on the drill press or on an arbor on the lathe?
I did it on my lathe but I don't remember how, It must have been from a flat sheet of phenolic material. Thanks @blahblahblahblah2933 🙂
@@DavidTipton101 Ahh seemed very small and difficult to hold especially it being phenolic. Good work!
I might have drilled a hole in a small piece of the sheet and screwed it onto a piece of dowel held in the chuck and machined it that way 🤔
Great creative work David. Thanks. 73 de KB7ICI......Bill
Thank you Bill 👍🙂
easy repair David need to use your CRO to see if the oss is running
Hi Ian. I could have used it but I knew the oscillator wasn't running and the transistor voltages were all wrong. I should have dragged it out to prove it 👍🙂
Top job on the Volume Pot Dave !
Great vid😊
Thank you @techobaz55 🙂
pnp silicon like 2n3906 is worth a try along with higher bias voltage. Beta for 10 is too low. check the other af117 also, may have very low beta too. 10k pot is about right. 2k is too low.
Thanks Mohinder. 2K is what was fitted 🤔
Very entertaining Dave - I thought I had tuned in to 'Shango' 🤫
Haha... thanks @xyredmax 😄
I have a old Windsor transistor radio has volume problem very loud adjusting it does nothing any suggestions
No, sorry.
Excelente trabajo. Saludos.
Gracias Eduardo 👍🙂
How are you liking your Brymen BM768? I have 3 Brymen meters, BM-869s, 235 and 525. Love them all. The 869s is very comparable to my venerable Fluke 189. What I love about the Brymen meters is they remember at the next power up where you had it set at last power down. Fluke and every other meter company goes back to factory settings at next power up. Great video as always David. Our favorite island radio genius Manuel digs Brymen meters too.
Hi @SIXSTRING63. The Bryman meter is great, I like how it can read AC and DC at once, that was the main reason for buying it. Yep, Manuel has a couple as well, can't get a better recommendation than that 😃 Thanks @SIXSTRING63.
foiled by the old dreaded solder blob! haha......look at you Mr. Tipton.... fabricating one good volume control from two.......The only thing missing from this video is "Dave Cinema"
I rate this video 4🍺🍺🍺🍺
It's the second time this week I've been fooled by the blob Buzz 😄 I don't have any Dave Cinema Buzz. I have videos of the kids and my wedding but nothing like your efforts. I'll be content watching yours 😄 Thanks Buzz 👍🙂
your viewers want to see you with hair!@@DavidTipton101
Nice one David!
Thank you Michael 👍🙂
Another boss video Dave ...thanks mate
Thanks Tim 😃
Very informative! Thanks for sharing... 73, Joe K4JGA
Thank you Joe 🙂
Nice save on the volume pot David.
Thank you Brian 🙂
Saludos Maestro:
Un Abrazo desde Cuba!👍
Hola Juan:
¡Un abrazo desde Australia!👍