Checking the Power Supply - Tube Radio Restoration Back to Basics part 2

Подписаться 24 тыс.

Просмотров 3,8 тыс.

50% 1

Only $5 for 10 PCBs and every new member get $5 bonus. + Express 24 hour / 48 hour service on www.pcbway.com/ ➠ ➠ ➠ In this, the second video in my 'Back to Basics' series, I tackle the power supply, starting at the absolute origin of all power, the mains inlet, through the switching, the transformer, and the selenium rectifier.
Some of my previously presented tricks are shown here, especially as regards testing the power transformer safely without connecting it to the mains, as well as replacing the selenium rectifier with silicon diodes.
I am taking it slow, as that is what many viewers have asked me to do, so I hope you get some useful insight from these videos.
I hope you enjoy the series, and invite you to comment.
🎥 Other videos in this series:
■ Back to Basics 1 - Tube Radio Anatomy: • The Parts That Make Up...
■ Back to Basics 2 - Tube Radio Anatomy: • Checking the Power Sup...
■ Back to Basics 3- Follow the B+: • How to Check the B+ Sa...
🙏 Want to support the channel? ●●●●●●
/ mcaldeira
paypal.me/macaldeira
#tuberadios #antiqueradio #radiorestoration
●●●● HUNDREDS OF OTHER VIDEOS TO CHOOSE FROM ●●●●
✿ DIY TEST GEAR: The title says it all:
• Zener Diode Tester - P...
✿ RESTORATION BUILDING BLOCKS: A series of videos showing detailed steps used the restoration process of tube equipment:
• How to safely check th...
✿ HowTo's: Various videos on some simple techniques and projects:
• Extend tube radio FM b...
✿ DIY CAPACITOR LEAKAGE TESTER PROJECT: One of the most viewed projects on my channel, with full design description and build instructions.
• Capacitor leakage test...
✿ DIY TUBE TESTER PROJECT: Complete design description and build instructions for this really handy device.
• DIY Tube Tester. Worki...
●●●● Plus full Playlists on some other completed restoration projects on this Channel ●●●●
📻 PHILIPS BX750A:
• Philips BX750A tube ra...
📻 TELEFUNKEN OPUS 2114:
• Telefunken Opus 2114 s...
📻 SABA UW-175-Z 3D:
• Saba UW 175-Z 3D tube ...
📻 GRUNDIG 1070:
• Grundig 1070 tube radi...
📻 SCHAUB-LORENZ GOLDY 58 type 3020:
• Schaub-Lorenz Goldy 58...
📻 BUSH VHF64:
• Bush VHF64 tube radio ...
📻 GRUNDIG 3060A:
• Grundig 3060a tube rad...
📻 TELEFUNKEN OPERETTE 8:
• Telefunken Operette 8 ...
📻 GRAETZ SUPER 171W:
• Graetz Super 171W tube...
📻 LOEWE-OPTA MAGNET 3737W:
• Loewe-Opta Magnet 3737...
📻 BRAUN ATELIER 3:
• Braun Atelier 3
📻 LOEWE-OPTA TRUXA STEREO 4741W:
• Loewe-Opta Truxa Stere...
📻 GRAETZ COMEDIA 616:
• Graetz Comedia 616 tub...
📻 SABA FREIBURG W2:
• Saba Freiburg W2 (WII)...
📻 GRAETZ MUSICA 4R417:
• Graetz Musica 4R417 re...

Наука

Опубликовано:

5 апр 2024

Ссылка:

Скачать:

Готовим ссылку...

Добавить в:

Мой плейлист

Посмотреть позже

Комментарии : 54

@JonRig 3 месяца назад

This series is so important as reference material. It is great that you are doing this. It's inspired me to dust off a Meersburg 9 project radio that I have had on the shelf for three years or more. From what I was told, the selenium rectifier started smoking and scared the pants off the prior owner so I offered to take it off their hands. I have not touched it since I got it but it seems absolutely perfect for this type of approach and treatment.

@electronicsoldandnew 3 месяца назад

👍 you can always trust me to ruin your relaxing evenings 😊

@JonRig 3 месяца назад

@@electronicsoldandnew You are on the money on that one! I got into it yesterday evening and before I knew it, it was 1-00am!

@electronicsoldandnew 3 месяца назад

Set an alarm … then press snooze a few times 😊

@DavidTipton101 3 месяца назад

Thanks Manuel 👍😀

@retro_tech 3 месяца назад

Fantastic series. Absolutely awesome that you're making this. This will be extremely useful for newcomers in the hobby, but it will also be very handy as a quick reference for me and many others. Great work!

@electronicsoldandnew 3 месяца назад

Thanks.

@bofor3948 3 месяца назад

Graet explanation! That explanation of the mains voltage applied to the unswitched side of the main plug appearing at all points through to the switch, is a classic explanation for the reason so many inebriated dads at Christmas times in past years were killed or seriously injured trying to repair Christmas tree lights. The lamps were only 12v or 20v but from the plug to the open lamp was 240V. Now fortunately we have transformers feeding LED's.👍🙂

@electronicsoldandnew 3 месяца назад

Yes, many don’t understand that the full voltage is there until the circuit is completed.

@lyntonprescott3412 3 месяца назад

Excellent work with very clear instructions. Well done sir.

@electronicsoldandnew 3 месяца назад

Thank you

@josephmagedanz4070 3 месяца назад

I'm really enjoying and learning from this series...thank you!

@electronicsoldandnew 3 месяца назад

Pleasure

@rikkies5249 3 месяца назад

Many thanks for the always excellent explanation regarding the restoration of old radios. It was a very clear explanation regarding the power supply part, and in particular the replacement of the selenium rectifier with a bridge rectifier and resistor. I am already looking forward to your next video.

@electronicsoldandnew 3 месяца назад

👍

@MarcelHuguenin 3 месяца назад

Great video Manuel, very well explained. I like your approach.

@electronicsoldandnew 3 месяца назад

👍

@mattking4267 3 месяца назад

Big, thank you for doing this series! I really appreciate all the extra detail!

@electronicsoldandnew 3 месяца назад

My pleasure

@greg5391 3 месяца назад

For those of us in North America, we usually find that the heater voltage is too high because the typical line voltage is 120v, rather than the 110 or 115 volts the radio originally was designed for. In order to avoid transformer heating and early failure of tube filaments, we need to use a dropping resistor in the mains ac before it gets to the transformer. Then, the B+ voltage, after the rectifier is adjusted, if needed, using a resistor. I have used readily available 25w or 50w chassis mounted resistors to lower the voltage delivered to the transformer.

@electronicsoldandnew 3 месяца назад

I’ve done that a few times when the radio only has the 220V tap, but fortunately this one has a 240V tap in the transformer.

@tubeDude48 3 месяца назад

As always, well done Manuel! 👌

@electronicsoldandnew 3 месяца назад

Thank you

@mackfisher4487 3 месяца назад

Nice tutorial professor

@electronicsoldandnew 3 месяца назад

Glad you liked it

@Wil_Bloodworth 3 месяца назад

Nicely done sir!

@electronicsoldandnew 3 месяца назад

Thanks

@poormanselectronicsbench2021 3 месяца назад

Great content as usual! When you are making "panelized" smaller PCB's from the standard 100 x 100mm size that JLC and PCBway give you discounts on ( like your diode rectifier and dropping resistor boards) , have you considered designing slotted cuts into the board to be able to break them down into the smaller boards instead of the V grooving? I remember you having difficulty snapping the V grooved boards apart, and they also hold you to the constraint of needing the groove cut to the full width or height of the board, whereas you can slot a board anywhere in any direction. JLC has no restrictions for slotting, except for needing the slot to be at least 1mm wide for non plated slots. You can create slots on the "board outline" layer of the design software, just like making a trace, or curve them if needed with circle or radius tools, you just need to leave some spots connected for enough rigidity when they are completing the rest of the board manufacturer. I am not a fan of the type of fuse holders that some European made radios, like that one have, as they seem to have a very poor design for contact with the fuse, and you definitely exposed that it's common for them to have bad contacts, create resistance, and then the resistance can create heat and damage.

@electronicsoldandnew 3 месяца назад

I have tried the slotted cuts, and they work fine.

@deepblueskyshine 3 месяца назад

VLF mains transformer supplied radio on european plug - no need to bother about correct mains phasing. This particular radio has two wire mains cable: if the chassis has to be ground connected, all you need is a regular 3-wire cable and plug; if it doesn't require grounding and can pass trained eye inspection to class 2 "double insulated" equipment - no need of changes, otherwise two directions of modifications are possible - convert it to grounded if possible, or isolate possible risk points, and ideally do both. What I remember from text books read 45 years ago is that selenium rectifiers are a bit like aluminum electrolitic capacitors that are being formed and tends to "loose form" without use, but they also have the advantage unlike irreparable germanium and silicon diodes to self heal partial/poind bridge like safety capacitors.

@electronicsoldandnew 3 месяца назад

👍

@edlowry1 3 месяца назад

Thanks so much for this, really appreciate it, currently working on Phillips BIF-460A

@electronicsoldandnew 3 месяца назад

👍 good luck

@edlowry1 3 месяца назад

@@electronicsoldandnew thanks also wanted to mention that the side by side comparisons of the schematic and what you are doing physically are so informative, your Photopea condensing of the schematic is also a great idea. Love the colour coding.

@electronicsoldandnew 3 месяца назад

👍

@ralphj4012 3 месяца назад

Loving this series. Interestingly (to me anyway), the selenium bridge seemed to be marked 32Hz. You could use 1mm solder pins for the dropper resistors. Socket (4:45), that's my college education down the pan, ho, ho.

@electronicsoldandnew 3 месяца назад

😊 a college education is never wasted. I recall our dean saying that we would leave varsity having learnt only ONE thing: How to learn 😊 He was right.

@paulperano9236 3 месяца назад

Something I have been doing is checking the transformer coils are NOT connecting directly to the chassis unless it is supposed to. Also you might want to briefly touch on the dim bulb tester and variac. Safety first !

@electronicsoldandnew 3 месяца назад

👍

@TheEmbeddedHobbyist 3 месяца назад

in the UK the fuse has to be in the live conductor, as our plugs are polarised. thus when the fuse blows all the remaining electrical circuits are at earth potential. Non polarised connectors are only allowed in double insulated equipment shown by the box within a box symbol.

@electronicsoldandnew 3 месяца назад

That makes it all a lot safer. Unfortunately we haven’t gone that route.

@edwardhannigan6324 3 месяца назад

Great video, very informative..learning loads..Thanks for posting..Ed..UK..😁

@electronicsoldandnew 3 месяца назад

Pleasure

@BobAndersson 3 месяца назад

One feature which never seems to get commented on is the way those (usually paper) capacitors where there is an outer foil get drawn on some of these old radios schematics, with the outer foil to the low impedance side. Modern foil caps don't have the black band showing the outer foil side which has led to many suggesting it no longer matters (as modern capacitors are smaller) but if it's worth recreating a shielded capacitor then maybe it's also worth taking note of the outer foil orientation on at least some caps in sensitive areas? It only takes a few seconds with an oscilloscope to determine the outer foil side of a cap (which also proves they aren't immune to hum pickup) but, of course, that does suppose access to an oscilloscope which is a bit of a luxury when starting out. Just my two cents... I really applaud the extra effort in creating this series as Manuel's videos were what prompted me to get into this as a hobby. 👏👏👏

@electronicsoldandnew 3 месяца назад

I always do the quick check with the scope and almost never mention it :) The shielded capacitor is slightly different, however. The external shield is directly connected to ground and not in contact with either of the actual capacitor legs. This is usually used in the audio coupling from a wiper of a volume pot, for example, where noise pickup would really make a big difference.

@jimf4492 3 месяца назад

I think this set of videos will be especially helpful. Question: Why not just swap the "hot" and neutral input wires so the hot wire is switched and fused? Is that because you just want to keep the radio in its stock form? Thank you!

@electronicsoldandnew 3 месяца назад

We don’t have a dedicated live and neutral plug in Portugal, so you can plug it it either way.

@jimf4492 3 месяца назад

@@electronicsoldandnew Thanks!

@Forensic1Man 3 месяца назад

Hi! Great video again! Are you going to offer up for us the small PCB that we also can order?

@electronicsoldandnew 3 месяца назад

It’s linked to the respective video.

@brianst.pierre6566 3 месяца назад

Is it typical to use WD-40 as contact cleaner? I've used it for many things but not that. Thanks for the videos. They're very helpful

@electronicsoldandnew 3 месяца назад

No, normal WD40 isn’t a good contact cleaner as it leaves a greasy residue that attracts dust. This contact cleaner is made by the same brand (WD40), but is meant as a pure contact cleaner. The fact that it has a similar label can be confusing 😊

@TheEmbeddedHobbyist 3 месяца назад

Do you have a high powered resistor decade box, as I've had quite a few boxes come back to my bench where they have overheated the low value resistors. Funny but they never seem to have noticed the change in resistance value when using it or the smell. 🙂 Then it looks like I'm always killing the boxes when I have to send them off for repair and calibration. Would have been great if I could just open it up and change the resistor myself but I would lose traceability. That's the difference between work and play 😞 A nice high power rheostat would be a good part for this test.

@electronicsoldandnew 3 месяца назад

Unfortunately my decade boxes are also low powered. Haven’t burned one out yet, but could happen.