Troubleshooting a Philips RF8 radio - Let's find out why it doesn't work!

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I was contacted about repairing an Philips RF8 radiogram chassis. I don't do outside work but I felt sorry for the gentleman and agreed to help him out. I expected it to have a few problems but when it arrived there was a long list of problems included. Please join me while I work through the list, some are mundane issues, others are real headscratchers.
Buy me a coffee ☕:
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Schematic for this radio:
www.kevinchant...
Woody's Hobbies, Philips Cartridge modification Video:
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Uncle Doug Video:
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I use Epidemic Sound for music and sound effects. Use the link below to sign up and I get a free month:
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Check out Carl's Capacitors eBay store for many radio parts and spares and the home of the all black capacitor. Once you've tried black, you can't go back: www.ebay.com.a...
Don's Old Radio Shed RU-vid Channel:
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The radio Mechanic Channel:
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The Code Machine Schematics - Mike:
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RetrObright:
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My Signal Tracer:
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My Digital Signal Generator:
The Signal Generator is a project kit from a local electronics magazine called Silicon Chip, there is a sister publication in the UK called Practical Electronics, it was featured in the April 2018 edition but mine has a oscilloscope function as well which I don't use. There may be a later edition in PE with that feature.
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Опубликовано:

10 сен 2024

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Комментарии : 267

@elc.eng.ihsanalmutari9298 Месяц назад

It's a real pleasure watching these magical hands.

@DavidTipton101 Месяц назад

Thanks Ihsan 🙂

@ellesmerewildwood4858 Месяц назад

Well, you do realize that this success will just add to your reputation for being the Montgomery Scott of radio repair.

@DavidTipton101 Месяц назад

"Beam me up Scotty" 😄 Thanks Ellesmere.

@clasicradiolover Месяц назад

He is pretty good.

@superhet7281 Месяц назад

Dave’s better than that - he’s the Mr. Spock of radio repair!

@johnrichardson7354 Месяц назад

Friday morning in Texas, and a video from Dave. What more does anyone need?

@DavidTipton101 Месяц назад

Good morning in Texas John. Thank you 🙂

@Plons0Nard Месяц назад

A great job once again. You are spoiling your customers 😊 (That's us, btw)

@DavidTipton101 Месяц назад

Thanks Nard 😄

@jonathanreedpike Месяц назад

I like your blend of diligence, pragmatism and humor, always a pleasure to watch you solve problems. The video production quality keeps getting better as well.

@DavidTipton101 Месяц назад

Thanks Jonathan. I try 😊

@martyh9309 Месяц назад

New workbench is fantastic!

@DavidTipton101 Месяц назад

Thanks Marty, it should work better for me 🙂

@kennethgibbons366 Месяц назад

Well done as usual David. I note with pleasure how much more confident you are then when you first started and very little phases you these days. As usual it is always a pleasure and so looked forward to.

@DavidTipton101 Месяц назад

Thanks Kenneth. I agree, I love learning and this hobby has been very good for me 👍🙂

@JerryEricsson Месяц назад

Thanks for the video, it is always a great morning when I can have Coffee With Dave! Update - Saw my Dr. and I am still cancer free 2.5 years after loosing my right kidney to cancer. Next week it would have been 55 years of wedded bliss for my good wife and I, I lost her to cancer 4 years ago. Funny how much of that damn disease is around, perhaps it is just that we now live long enough for it to develop or something like that; who knows....

@DavidTipton101 Месяц назад

Thanks Jerry. Well done staying cancer free, an awful disease. Living longer does mean we are more likely to develop age related diseases ☹️

@cliffjones7868 Месяц назад

I am impressed. With the step by step detailed explanations, clear voice. I learned a lot about it. The reasons for the resistors and caps were completely understood. Thank you, I wish in the mid 60s I had you in my teen years for a teacher. Thanks!

@DavidTipton101 Месяц назад

Glad it was helpful Cliff, thank you 👍😊

@electronicsoldandnew Месяц назад

Another “Good Friday” for me 😊 Who says you only have a Good Friday at Easter? Also learnt something I didn’t know: 360million pigs????!!! Thanks again Dave. Have a great weekend.

@DavidTipton101 Месяц назад

Haha... thanks Manuel. Yes, lots of feral pigs roaming about, I think it's more like 20 something million... and about one million camels 😊

@clasicradiolover Месяц назад

That's a lot of ham.

@catey62 Месяц назад

@@clasicradiolover Lol, with Dave's senses of humour, there's always plenty of ham on this channel. 😂

@clasicradiolover Месяц назад

@catey62 I rather think he's usually deadpan, but I loved the one in which he was working for his grandchildren

@radio-ged4626 Месяц назад

Nice to see a different approach to working with valve equipment. Usually see restoration, solving problems along the way. But this is more real, dealing with reported faults by the owner. As an ex- repair and service engineer this is more like what I used to do. Except the customer would be less descriptive and more emotional if you get what I mean 😊

@DavidTipton101 Месяц назад

Haha... yes I know what you mean radio-ged. It was a good exercise to just do the troubleshooting and this one had an unusual fault which made it more interesting 🙂

@knifeswitch5973 Месяц назад

Always learn something valuable from your videos Dave. Was great to lay in bed a little longer this morning and watch this one. New setup looks great. ❤

@DavidTipton101 Месяц назад

Thanks Knifeswitch. I'm looking forward to using the new bench setup, a bigger bench as well 👍🙂

@ricke.2205 Месяц назад

One of the many things that amazes me about radios, is the never ending variety of radio circuitry design. Not to mention, the variety of the overall designs of radios. Limited only by the manufacturer's technical knowledge and imagination.

@DavidTipton101 Месяц назад

Yes, many ways for doing the same thing with similar results. Thanks Rick 👍🙂

@stephengorin3059 Месяц назад

Love the new working bench, every thing at hand.

@DavidTipton101 Месяц назад

Yes, it will need some adjustment as I go along but excited to use it 🙂

@MarkMcCluney Месяц назад

Blimey! Roy and HG are still going? They've got a lot of Ozzie staying power. Thanks Dave, this was another very enjoyable and instructive trek. That sig gen is a beauty! Thanks again mate.

@DavidTipton101 Месяц назад

Yeah, they are still going, just a bit older now 😄 Thanks Mark.

@daleburrell6273 25 дней назад

...the word is: "AUSSIE"...(!)

@hestheMaster Месяц назад

You not only are a great electronics restorer David but you watch the same YTer's as I do. This is one great community of vintage tech guys showing how it's done here on RU-vid. The owner was probably estatic about you getting her up and running like a champ again. Steve from Illinois, USA

@DavidTipton101 Месяц назад

Hi Steve, I totally agree, the fellow YT's I have interacted have been pleasant and helpful. The owner was very happy with the result 🙂

@stephengorin3059 Месяц назад

Great work on the philips FR8, Nice to see another one of these radio grams restored. As with the electrolitic caps i have found that the HT pins are a little bit close to the chassie. The ones i have done i have "nibbled" the chassie to give the HT pins a bit more clearance and not short out to ground. Restinging any radio a final trick is to paint the knot s with nail varnish ( a old bottle will last for ages ). This is obsorbed buy the dial cord and stops the knot from working loose. Great work David , Keep up the good work and as usual i will be looking forward to your next adventure.

@DavidTipton101 Месяц назад

Hi Stephen, thanks. Yes I did nibble away at the edge in one spot and filled around the terminals with liquid insulation tape. I did put nail polish on the dial sting knots, I always do. Cheers 🙂

@dogribmoon Месяц назад

The new work space looks really functional. You will save so much time not having to get equipment set up and put away!

@DavidTipton101 Месяц назад

It was too much trouble setting up equipment all the time and I would avoid it if there was another way. Thanks dogribmoon 👍

@stanleycostello9610 Месяц назад

🎶 Somewhere my love, there will be songs to sing." 🎶 With David at the helm, we can expect the best. (I have this album.) Have a good weekend.

@DavidTipton101 Месяц назад

It must be a best seller album Stanley 👍😄 Thank you.

@stanleycostello9610 Месяц назад

@@DavidTipton101 I remember my parents went to see "Doctor Zhivago." The women's fashions had a Russian theme that year, so my Mom had a mink hat. They went to a fine restaurant and saw the movie at the Trans-Lux theatre. 70 mm. My Dad bought the sound track from the movie.

@DavidTipton101 Месяц назад

70mm was fantastic, I saw The Great Race in 70mm, it used three projectors I think, why don't they do it anymore. It sounds like it was a good night for your Mom and Dad 🙂

@stanleycostello9610 Месяц назад

@@DavidTipton101I saw "Camelot" in 70 mm. It was magnificent.

@MrCarlsonsLab Месяц назад

Fantastic looking bench Dave! Thanks for taking the time to share your videos too :^)

@DavidTipton101 Месяц назад

Thanks Paul, I'm trying to keep up with you, not much hope thought👍😄

@jogden6632 Месяц назад

Dave, new work station looks good. Love that you included mains for radios in North America!

@DavidTipton101 Месяц назад

Thanks Jason, I have some 120 Volt test gear as well 🙂

@jims2222 Месяц назад

I also learn something from each one of your videos. Thank you Dave.

@DavidTipton101 Месяц назад

Thank you Jim, me too 🙂

@tubeDude48 Месяц назад

Nice layout on the bench! 👍 YUP! I follow Uncle Doug as well. So glad to see you use DeoxIT Fader F for POTs! So many, (so called) repair people will use plain old contact cleaner, that in time, will form a film, and have the same problem re-appear!

@DavidTipton101 Месяц назад

Thanks TubeDude. Yes, and used sparingly it works very well 👍

@paulziminskin2ghr282 Месяц назад

Nice job Dave. You got lucky with that IF transformer ,That would have been a real bear if it needed to be rewound ,take care Dave

@DavidTipton101 Месяц назад

Thanks Paul, I have a spare so it would have been OK either way. It's the antenna induction tuning coil 👍🙂

@Jan_Talcott_100 Месяц назад

I haven't even watched the complete video yet... I want your new work station. It's fantastic!!

@DavidTipton101 Месяц назад

Haha... thanks Jan 👍🙂

@Buzz1151 Месяц назад

Hi David...that was a good repair, and cheap too! bravo!👏👏 Dickel has a joke for you below. A bald guy sees David Tipton at the local pub enjoying a pint and walks up to him , and asks politely, "Hey, mate, I'm new in town. Do you know where I can buy a toupee?" David replies "Not off the top of my head."🤣😂😁

@DavidTipton101 Месяц назад

Hi Buzz, thanks. Haha... that's a good one. Dickel is way funnier than you and I put together 😅 A new video from you just popped up, a coffee is in order while I watch it 📺... bit early for a beer ☹️🍻

@Buzz1151 Месяц назад

@@DavidTipton101 🍺🍺🍺🍺

@mikecass8306 Месяц назад

Great repair, love the new workbench, thanks David for another great stream 😃

@DavidTipton101 Месяц назад

Thanks Mike 🙂

@Donno308 Месяц назад

Hi David. A very nice job, as always. Interesting stuff about cathode bypass caps. I watched Uncle Doug's video - you're right - he's a good teacher. Love the new work bench. It would be SO nice to have everything conveniently at hand. One day ... I'm not really jealous. I'm not! Really! Mr. Carlson probably is though. Thanks for another Friday evening highlight 😀

@DavidTipton101 Месяц назад

Hi Don, I devoured Uncle Doug's videos in my early radio restore days, it's a pity he only does amps and not the full radio. I somehow remembered his video on bypass caps and found it in a few minutes to refresh my memory. The new bench is working well at the moment, I'm struggling with new camera mounts and LED lighting but will get it sorted in due time. Thanks Don 😊

@Donno308 Месяц назад

@@DavidTipton101 Hi David. Yes I have trouble with LED lights strobing in the videos. I've got a couple of flouros over the bench & use LEDs as infill. They're ok strobe wise so long as I keep them some distance away. I'm still experimenting with the overhead cam. At the moment it's fixed position and I just move the chassis under it. I was getting too much camera shake otherwise. Cheers

@DavidTipton101 Месяц назад

@Donno308 Your use of the overhead cam did not go unnoticed Don.

@jamesbruno5896 Месяц назад

New bench looks great & you went above expectations on the repairs!

@DavidTipton101 Месяц назад

Thanks James 👍🙂

@brianwood5220 Месяц назад

Thanks Dave. It's a pleasure to watch you work. Have a great weekend.

@DavidTipton101 Месяц назад

Thank you for your support Brian 👍🙂

@chriskilby5300 Месяц назад

Hi Dave loved this adventure so many faults to fix. I've always been into electronics as a hobby. I first started playing with valve radios (lucky I'm still alive)at about 13 yo. I am close to retirement and wanting to get back into it. I've built up quite a few radios and test equipment. Your videos are such a wealth of knowledge. Don and Frank also great inspiration. Thanks again Dave.cheers

@DavidTipton101 Месяц назад

Thank you Chris. All the best in retirement when you get there and a new hobby to enjoy 🙂

@martinoakley6651 Месяц назад

As always, brilliant work and I always learn something. The cartridge modification was genius and will prompt me to look at a similar issue on my Bush radiogram. Looking forward to the next Radio Adventure!

@DavidTipton101 Месяц назад

Thanks Martin. The cart mod worked well and sounds great even with these cheap cartridges from China 👍🙂

@ceebee23 27 дней назад

The work bench is awesome .... and as always a great job David!!!!!!

@DavidTipton101 25 дней назад

Thanks Chris, I happy with my bench so far, I might tweak it a bit but it's working OK so far 👍🙂

@hazevthewolf178 26 дней назад

Your videos are just getting better and better. I find them really relaxing to watch. Kudos for the repair job that you did on this one.

@DavidTipton101 25 дней назад

Thank you Mr Wolf 🙂

@chrissmith7655 Месяц назад

Hi Dave , yet another super job and learn from every one of your uploads. Many thanks from UK.

@DavidTipton101 Месяц назад

Thanks Chris 🙂

@Antony_Jenner Месяц назад

Nice one Dave, I've got one of those Philips boards fitted in an old South Australian Railways telephony box. Worked a treat when it was the workshop amp running into some vintage Richard Allen speakers. Thanks for the video. Oh and got to love Rampaging Roy Slaven and H G Nelson

@DavidTipton101 Месяц назад

Yep, the set works well as an amp. I don't know how long Roy and HG have been going, it seems like an age. Thanks Antony 🙂

@ibrahimkocaalioglu Месяц назад

Good job done. You are really an expert. Your Olympic team was very succesfull as well. 🥇

@DavidTipton101 Месяц назад

Thanks Ibrahim. We are very proud of our Olympic team, thay have worked hard 😊

@EsotericArctos Месяц назад

I love seeing these old radios brought back to life. Regarding the enameled cable, I was taught that a hot soldering iron is the best way to melt the enamel and tin it, and that seems to work for me on all I have done. It's kind of a shame that the AM band was completely renumbered. I've found virtually all early Australian radios only have the station call signs on the dial, and virtually never have the actual frequency. Not sure why Australian radios were done that way. Most Eu and US radios had the actual frequency or wavelength on the dial. Still great to get them working though as modern radios just don't sound the same

@DavidTipton101 Месяц назад

I haven't always had success using an iron on the enamel, I really didn't need to remove any as the end still had solder on it. I couldn't see it as well as the camera showed. We knew the stations by the callsign, no need to remember the frequency. It was a good system. If I wanted to listen to a station I could select it from the dial and not search for it roughly about 'there' on the dial. Some radios had the frequency printed along the bottom but it wasn't really needed. Thanks Brendan 🙂

@MCML50 Месяц назад

Hi David, i must say that you nailed it again a very nice job dan.👍👍.

@DavidTipton101 Месяц назад

Thanks Claes 🙂

@aaax9410 Месяц назад

Hi Dave great video , have followed UncleDoug for years , learnt a lot from him now learning a lot from you on radio , also from the South East cheers mate :)

@DavidTipton101 Месяц назад

Uncle Doug was a big help when I started out, he explains things well. Damn cold here at the moment 🙂

@aaax9410 Месяц назад

@@DavidTipton101 Heater is on mate lol

@josephmagedanz4070 Месяц назад

Nice work with the radio, and, yes, I learn something from each of your videos, too (and from Uncle Doug, too). Thanks for sharing.

@DavidTipton101 Месяц назад

Hi Joseph, Uncle Doug was very helpful explaining how how the amp stage and valves worked. I think you and I both learn something when I do a radio 👍😄

@mrgunn2726 Месяц назад

A fine Tippton treat to enjoy with my morning coffee. Well done!

@DavidTipton101 Месяц назад

Thank you mrgunn 🙂

@neilsradios Месяц назад

Nice work as ever, especially the switch. Whenever I dismantle one of those rotary switches we end up with a long gap between video sections and editing out of many words that can't be put on RU-vid 🙂

@DavidTipton101 Месяц назад

Haha... I can imagine Neil. This one was very easy, I was surprised it went back together without any effort 👍🙂

@scask Месяц назад

Nice new bench Mr David "Carlson" Tipton...😁

@DavidTipton101 Месяц назад

Long overdue 😊 Thanks Scask.

@scask Месяц назад

Very posh (Scask aka Darren from Droitwich) 😉

@DavidTipton101 Месяц назад

Hi Darren 👋😊

@YellowJello57 Месяц назад

Great stuff as always, David.

@DavidTipton101 Месяц назад

Thanks H 🙂

@chrisrobson8540 Месяц назад

Fantastic repair as usual....love to see a full restore on your cabinet

@DavidTipton101 Месяц назад

Hi Chris, That is my plan 👍🙂

@ralphmans Месяц назад

David, nice to see you again, I was getting worried, welcome back.

@DavidTipton101 Месяц назад

I'm bang on schedule Ralph, a video every three weeks. Thanks 👍😊

@LarryDeSilva64 Месяц назад

wow you really outdid yourself troubleshooting this radio. With problems I would never figure out . But you took them one at a time in your own methodical approach. Thanks for a great video.

@DavidTipton101 Месяц назад

Thanks Larry 🙂

@Joe-KN4IFI Месяц назад

Cracker Jack job David. Always a pleasure to watch your work. 73 Joe

@DavidTipton101 Месяц назад

Thanks Joe 🙂

@TheUltimateRecycler Месяц назад

Great job as usual Dave! I like the sneaky way you've been able to free up space in cupboards for more radios by having a bigger workbench for all the test gear! Don't worry - I won't tell Karen of your cunning plan! 😉🤣

@DavidTipton101 Месяц назад

Thanks Chris. Ahh... yes, we men need to keep one step ahead don't we 😅

@decoder6379 Месяц назад

Я регуляторы промываю изопропиловым спиртом. Тоже хорошо помогает. Лайк поставил.

@DavidTipton101 Месяц назад

Спасибо, ДЕКОДЕР 👍🙂

@user-tu9lm3lp2n Месяц назад

A fresh Video from David,the morning couldnt be better,on this raining day in germany.

@DavidTipton101 Месяц назад

Thanks Tobias 🙂

@hbhmhbhm Месяц назад

Great work on the Philips and the new bench looks great too!

@DavidTipton101 Месяц назад

I'm very happy to finally get the new bench together, I have been planning it for a year😄 Thanks @hbhmhbhm.

@erikdenhouter Месяц назад

Nice repair David. What shows for me is that not all Philips are a pita to work on. Nicely open, easy to reach. Even the dial cord was simplicity itself. And the dial accuracy was the cherry on that cake

@DavidTipton101 Месяц назад

I don't mind these Philips sets at all Erik. I think it was designed in Australia, not sure. Thanks 😊

@Ragnar8504 28 дней назад

I think the larger Philips sets were generally decent to work on, the small ones are the real pain.

@erikdenhouter 28 дней назад

@@Ragnar8504 I can back that up with my ever lasting repair on a B2X63U. Lacking the experience in tubeland, it scares the hell out of me to work live on it.

@Ragnar8504 27 дней назад

@@erikdenhouter In that case I'll sometimes use probes that I can clip onto points while the radio is off, then turn the radio on and do my measurements. Doesn't work for aligning the set though, only for checking voltages.

@erikdenhouter 27 дней назад

@@Ragnar8504 ☝Yes, that is almost the only way to do it safe. Still I cannot put my finger on it, need so many measurements, and the lack of experience in tubes doesn't tell me what to expect where. I gave up a half year ago 😖 Some day I will pick it up again....

@ShannonFerguson Месяц назад

Your new setup looks awesome!

@DavidTipton101 Месяц назад

Thanks Shannon 👍🙂

@JonRig Месяц назад

Great vid - lot's of fantastic insights and that little broken wire in the can was a real lucky find! Fascinating! And the new workbench looks great! Well done on that!!

@DavidTipton101 Месяц назад

Thanks John. It was good I could repair the coil, it would be tricky to rewind 🙂

@JonRig Месяц назад

@@DavidTipton101 One things for sure - if anyone could rewind a coil it would be you!!! You are the master at that, given the magic you hace done with transformers and speakers!!! Stunning work!

@johnburns6422 29 дней назад

Philips drive cord systems/ you are a Brave Man , very good job well done , Many Thanks ☘☘☘☘☘

@DavidTipton101 28 дней назад

A piece of cake that one John. Thanks 👍🙂

@haythamchannel3553 Месяц назад

Good morning David. Great work

@DavidTipton101 Месяц назад

Good morning Haytham, thank you 🙂

@ChuckKirchner-se6ib Месяц назад

You can't go wrong with Uncle Doug. He's one of the best!! Cheers, Dave

@DavidTipton101 Месяц назад

Absolutely, an outstanding teacher and a perfectionist as well. Thanks Chuck 👍😊

@nathkrupa3463 Месяц назад

Good work David sir you are awesome ❤😊❤😊thanks for sharing this video sir 😊😊😊❤❤

@DavidTipton101 Месяц назад

Thanks Nath. my pleasure 👍🙂

@theprisonernumbersix996 Месяц назад

Encore un super travail et une video passionnante , merci David. "Be Seeing You" ! N°6 👌

@DavidTipton101 Месяц назад

Thanks you N°6 🙂

@richb419 Месяц назад

Hi Dave, nice work as always! Rich from across the pond

@DavidTipton101 Месяц назад

Thanks Rich 🙂

@iantyler4045 27 дней назад

Another triumph. That ceramic cartridge hack is brilliant. The Chinese ones are a very poor copy, designed to look the part and that's all (like most of their stuff!). Your workshop looks so neat and tidy. It's given me the inspiration to redo mine. Cheers.

@DavidTipton101 27 дней назад

Yes, the carts are cheap, you could get the Pfanstiehl cartridge the Chinese copied for a little bit more if you were serious, I might get a few myself 🙂

@hooshangyadegar1250 Месяц назад

I enjoy watching this video .❤

@DavidTipton101 Месяц назад

Thank you Hooshang 🙂

@alpcns Месяц назад

Thanks David - top work, as usual. That device sounds really good now. Many naughty caps!

@DavidTipton101 Месяц назад

They are a good radio thanks alpcns 😊

@jimburns348 Месяц назад

Great video David. Your sleuthing ability would rival Clouseau.

@DavidTipton101 Месяц назад

Absolutely, I based my life on his teachings 😅 Thanks Jim.

@ChrisSwenson 9 дней назад

Hi David. Where do I begin? Such a good video, on all levels; THOROUGH (all caps!), excellent camera work (as usual), presentation, superb detective work, walking us through the journey, the "nice" Mission Impossible typing touch, and the satisfying summary. BTW: starting off with your work station improvements, brings back youth memories of sharing "what I got" with friends - the day after Christmas. It's Labor Day in the USA, so I'm enjoying my day off with the added treat of anticipating the viewing of your "next" video, which you downloaded 3 days ago. Fine Job David! -Chris

@DavidTipton101 7 дней назад

Thank you Chris. I'm very glad you enjoyed it. I trust you enjoyed you day off 🙂

@mackfisher4487 Месяц назад

Grate job David, your new test bench looks good. The 120VAC us receptacle is a nice touch how about having up for on, and down for off the way we do it.

@DavidTipton101 Месяц назад

Haha... I didn't think of that 😄 Thanks Mack.

@Steven_Bennett_YT 28 дней назад

Can I give a bit more info about cathode bypass David. Back in the 20's and 30's radios used valves that had no cathode, only a glowing wire called the filament to emit electrons. Both mains and battery sets had to use an extra battery called a grid bias, or C battery, which provided the negative voltage to keep the grid more negative than the filament, or the filament more positive than the grid, whichever way you want to view it. The reason for the extra battery was that the indirectly heated valve, with an electrically isolated cathode, had yet to be invented so all the valve's filaments were joined together via the A battery or Low Tension supply. Then once indirectly heated valves, with cathodes, were available someone came up with the idea of including a resistor in the cathode circuit that could use the cathode current flow to raise the cathode voltage, known as self bias - individually for each valve. Good idea so far but the resistor created a large amount of negative feedback from DC to higher frequencies, greatly reducing the stage gain. Adding a cathode bypass capacitor virtually eliminated the negative feedback from low frequencies, say 20Hz to the top of the audio band, say 20KHz and higher. In other words the capacitor acts like a short circuit at all audio frequencies, maximising AC gain but the capacitor is an infinite resistance at DC leaving the cathode resistor to continue to provide DC negative feedback, which stabilises the DC operating point of the valve-tube.

@DavidTipton101 27 дней назад

Nice, thanks Steven. That is perfectly presented and understood 👍🙂

@andyfairman7812 Месяц назад

Fantastic as always! Thanks Dave!

@DavidTipton101 Месяц назад

Thanks Andy 🙂

@greggsvintageworkshop8974 17 дней назад

Really nice troubleshooting techniques David! You have it playing very nicely now for your friend. Nice repair on the stylus as well!

@DavidTipton101 16 дней назад

Thanks Gregg 😊

@perunut4656 20 дней назад

Great video, really interesting to see how you fault find, particularly with high voltages. Only thing I have here thats high voltage is my inverter, and the original one had an internal arcing fault after a few weeks use, but was told by the manufacturer not to touch it :)

@DavidTipton101 19 дней назад

Thanks Peru Nut. That sounds like good advice ☹️

@seankearney2592 Месяц назад

Nice one Dave,as always Your Magic Hands works Wonders.....

@DavidTipton101 Месяц назад

Thank you Sean 🙂

@matambale Месяц назад

Loved it, your videos are always a treat, thanks David.

@DavidTipton101 Месяц назад

Thank you Matambale 🙂

@1974UTuber Месяц назад

I thought for sure it was gonna be a case of a cracked board. Nce job as always

@DavidTipton101 Месяц назад

Well, yes, it could have been 1974UTuber. Thanks 👍🙂

@billnicholson2470 Месяц назад

Really nice workstation David. Great job on the radio detective work as always. 73 de KB7ICI.....Bill

@DavidTipton101 Месяц назад

Thank you Bill 🙂

@wayneshirey6999 Месяц назад

Nice work as usual. I'd love to see a video of your putting that snazzy new workstation together.

@DavidTipton101 Месяц назад

Haha... it took me a week to put it together Wayne, it would have been a long video with a lot of beeps 😄

@sheldonlatimer6688 Месяц назад

Once again great job well done

@DavidTipton101 Месяц назад

Thanks Sheldon 🙂

@lyntonprescott3412 Месяц назад

Nice one David. Hope you and the family are all well. Lynton

@DavidTipton101 Месяц назад

Yes we are, thank you Lyndon 🙂

@davidhamm5626 Месяц назад

I like the segment intros, It's like of like mission "possible" ! Great work Sir.

@DavidTipton101 Месяц назад

Haha... it was a bit, I must be having flashbacks 😅 Thanks David.

@paulsto6516 Месяц назад

Good show, man!

@DavidTipton101 Месяц назад

Glad you enjoyed it Paul, thank you 😊

@edwardhannigan6324 21 день назад

Fab job, great to follow and learn..Take care..Ed..UK..😃

@DavidTipton101 21 день назад

Thanks Ed 🙂

@nzs316 28 дней назад

"Dr.Zhivago" is on your top of list, must listen to, music! Thinking back that there was a woman that got run over in the train scene and there was no interruption in the filming and the room filled with ice during the winter...heck i was 5 when that came out.

@DavidTipton101 28 дней назад

Hi Neil. I don't think I have seen the film. I do recall a woman trying to board the train fell under the train and was injured. I can't remember if they kept that bit of footage in or not 🙂

@nzs316 28 дней назад

@@DavidTipton101 they kept the scene where she tried to climb on the train and then falls but they don’t show her going under the train. Kinda eerie to witness a persons final moments.

@eddyaudio Месяц назад

David a great Refurbishment of Philips RF8 Radio Gram those Blue Philips electo Caps they are problem with age Philips was excellent resistor but they used IRC Resistors in all their products Philips Mustard Cap were trouble free they were a excellent cap, I like new bench layout and the 120volts outlet a guess had a separate transformer feeding it in all a Excellent refurbishment David,Ian,

@DavidTipton101 Месяц назад

Hi Ian, Thanks. The blue caps are replaced and I check all the resistors which seem to be a mixed bag of good and bad. I have had a few of the mustard caps go noisy but usually good. Thanks, I have a big 240 to 120 Volt transformer under the bench 👍🙂

@ralphj4012 Месяц назад

Thorough, as always, though I did expect to see vertical smoothing capacitor clips, chassis drilled to accommodate, painted black and with white Letraset applied to reproduce any obscured lettering, ho, ho.

@DavidTipton101 Месяц назад

Haha... thanks ralph 😄

@SuperFredAZ Месяц назад

Yes, for a high gain (gm or Mu) the gain reduces the larger the cathode resistor if you bypass the cathode resistor. The cathode resistor is there to provide negative bias (relative to the grid). To get maximum gain the cathode resistor is bypassed. value of the capacitor should be small compared to the cathode resistor say at 50 Hz.

@DavidTipton101 Месяц назад

Yes, thanks Fred 👍🙂

@Peugeot306 Месяц назад

Good evening David.

@DavidTipton101 Месяц назад

Morning Paul 🌅

@OIE82 4 дня назад

Very well done, repair and video. One thing would add educational benefit, and that would be to show where you get the specs for the adjusting and alignment. Eg. How did you know that the dial pointer should be on what mark at what frequency? The cutting back and forth would require more video editing, I guess. Anyways, thank you for all the great content.

@DavidTipton101 3 дня назад

Good point Odyssey, I put a link to the Schematic in the description below the video. I have done these so many times I forgot to show what I was doing. Thanks 👍🙂

@OIE82 2 дня назад

@@DavidTipton101 Thanks for the link. More than anything else, finding a new source that may have complete documentation is always a plus. Most of the time I am happy with a close schematic.🙂

@clasicradiolover Месяц назад

Hey guy. I love that piece by Glenn Miller. I think I first noticed it on an episode of Doctor Who with Rose.

@DavidTipton101 Месяц назад

Here you go classical: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-_CI-0E_jses.html

@clasicradiolover Месяц назад

@DavidTipton101 Thanks. I have it on my Spotify list, too. For a 59 year old, I have some esoteric tastes. I listen to my Grandparents and parents eras as well as my own. And in foreign languages. Especially Spanish. And the old time radio shows before TV

@madrafboy Месяц назад

You're a star Dave. Anther good video mate.

@DavidTipton101 Месяц назад

Thank you John 😊

@aussiedazvk4djh889 Месяц назад

Couldn't hear KQ. Good fix Dave. 👍🍻

@DavidTipton101 Месяц назад

It's an ad station now with a bit of sport in there. Thanks Aussie Daz 🙂

@abcsd1254 Месяц назад

Very interesting that the caps in the cabinet were Ducon when the amp looked like all Philips. I wonder if they assembled the Radiogram in Australia with components made in Holland.

@DavidTipton101 Месяц назад

Good point @abcsd1254, I have no idea 🤔

@ladamurni Месяц назад

Nice one David, I enjoyed watching it!

@DavidTipton101 Месяц назад

Thank you ladamurni 🙂

@lookoutleo 28 дней назад

I love watching you do these great restorations , wish you could do me a tuner amp so could connect my record player and listen to my Jimmy shand 78s

@DavidTipton101 27 дней назад

Jimmy Shand, the accordion player! That's an old one Leo 🙂

@lookoutleo 25 дней назад

@@DavidTipton101 I have loads of 78s from the 20s on, would love to hear them with valves , in mean time I listen to them with my 1980 music centre with 60s speakers :) I have loads of Ambrose and his orchestra , pop music of the 30s :) so modern

@JE-hm7jw Месяц назад

Good Show Mate + :-)

@DavidTipton101 Месяц назад

Thanks JE 👍

@georgeallen8860 Месяц назад

Ha Ha David i am learning ... Please keep teaching

@DavidTipton101 Месяц назад

Will do, thanks George 🙂

@raymondmenard5444 Месяц назад

Wow ! This is simply another troubleshooting master class Dave, geez to think i struggle for weeks just to find a faulty resistor or something else wrong on a set makes me feel, well you know small... But on the other hand, i know i have improved quite a bit thank's to you. Now about the tiny broken inductor wire you located and masterfully repaired, i think luck has nothing to do with it my friend, after all just studying the schematic and analyzing the symptoms you went straight to the right part of the chassis.. What you call luck i call it experience and intelligence and we all benefit from you big brains ha ha ha, am i starting to sound gay again ? Have a safe return home mate 🙂

@DavidTipton101 Месяц назад

Hello Raymond. I agree, experience plays a big part in repairing anything, or anything we face in life really. I think I was referring to the broken wire being accessible more than anything. Having said that it would have been a hoot to dismantle the tuner to access the full coil, repair it and align the two coils using the rod immersion adjustments on the top of the tuner. Thanks Raymond, we are back home safe and sound, thank you 😊