D-lab series Basic Training How to repair output tube red plate negative bias & safety lesson

A common failure on vintage tube amps. This video will teach you the things to look for if your amp is red plating and destroying your output tubes. The price of tubes is crazy high these days. Time to narrow down failure modes, perform some preventative maintenance, monitor the health of your classic tube amplifier. Its worth the effort. Plus, I will demonstrate a high voltage safety hazard waiting to bite you! Note: D-Lab will be launching a new Tech School series on Patreon soon. This is the next level up training following your basic training. Launch date will be announced. See: www.patreon.com/dlab_electron...

[@CC-te5zf]

Most excellent explanation of fatigued metal! Just replace the sockets - or have someone do it. Sadly, there's guys on KZbin showing them bending these. Super dangerous on so many levels.

[@rciancia]

Well done, short, concise and to the point info that can SAVE YOUR LIFE !!! Awesome my friend. I love being on Patreon as well with you, good stuff

[@peterflynn850]

Thank you, Terry. Brilliant short and focused training module.

[@Finom1]

Bless you Terry, for sharing your life and wisdom with us!!! Everyone smash the like button, subscribe and shar worldwide!! Terry is keeping us safe, we should show him respect and get him on 100K subscribers, let's go!!!

[@ericedelman]

I have seen others suggest it is a good idea to tweak those pins back into shape. Metal fatigue. Good point! This is why I had output issues with my 1980 Fender Deluxe Reverb. Once I changed all the 3 octal sockets, everything stabilized.

[@peteleoni9665]

I have a 42 year old amp. I reformed the tube sockets around 20 years ago. Waiting for it to fail, but I warned my son to warn my grandson.

[@roberthurless3295]

Good , solid advice. Thank you Terry.

[@chris-the-bodge-sculptor]

Thank you for taking the time to share your knowledge with us

[@joshuahonel7321]

Love this series.

[@jdmccorful]

Good tips! Thanks.

[@edwardhannigan6324]

Wow Terry so much info and safety tips..Sure learn loads from your training videos..Great subject, and these tips etc. could save someone's life..! That old rat is getting popular..🤣🤣 Ed..uk..😀

[@pauldow1648]

Well done

[@bernhardnizynski4403]

Great advice!

[@johnseymour5223]

I would absolutely love to be able to do electronics repair.. But, I am badly color blind.. and the wife gets very tired of me asking is this blue? LOL!

[@cheycasters]

Terry, years ago I sak about that cool logo D-Labs T-shirt??!!!! That red outr shot was a cool logo!

[@d-labelectronics]

Yes, I have a fellow working on them. Hopefully available soon

[@preiter20]

@@d-labelectronics I need some D-Lab swag! Maybe Snauzoramus, Kobbler, and Troll could have their own swag? I don't know which is worse, a red plate or a red shirt on the away team.

[@d-labelectronics]

Just home from the shirt shop. looking at 3 weeks delivery

[@voxpathfinder15r]

I had one tube redplating on my Carvin Belair, but using some DeOxit and wire brush on the prongs as well as the sockets seemed to stop the red plating. Ironically while using a bias probe tool, the glass envelope busted up on that one tube while handling it. So I think it was partly that tube itself was on its way out. After replacing that one tube, still no issues

[@pauldow1648]

Thank you.

[@dingalarm]

Thanks Terry! This may be obvious, but as a closing comment, the filter capacitors should be discharged before replacing the worn tube sockets.

[@billbates7810]

Hi, I enjoy watching your videos! I have a hifi tube amp that intermittently goes red plate, I have replaced all the electrolytic caps, all the decoupling caps and fitted high quality ceramic tube bases. I have gone through all the resistors and checked they’re in spec, output transformers are good (no shorted turns), any ideas most welcome, I’ve also checked the tubes on a tube tester and swapped tubes round! God bless, Bill.

[@ne2i]

When the sockets get old The sockets lose tension due to heat. This style of socket are prone to that as the tubes roast the sockets.

[@josephmagedanz4070]

How about offering T shirts with your logo? I'd like one. Nice series...thanks.

[@d-labelectronics]

Yes, I have a fellow working on them. Hopefully available soon

[@jimcastillo8950]

Thumbs up Terry, what brand of tube sockets do you recommend and what brands to stay away from ? thank you.......

[@nickvictor7398]

In your intro you should say some kind of catch phrase that describes why you call it d-lab

[@Wizardofgosz]

That one ohm resistor you use to be able to determine bias current? How many watts is it, and what pin are you going to on the sockets?

[@infectionsman]

I have some sockets on an amp where the big insulator piece is loose in the metal mounting piece that is riveted to the amp. When grabbing the tube and tweaking it, the insulator moves with the tube. The pins are tight but the entire tube can rattle because the insulator is not solid against the mounting metal thingy. Should I replace the sockets? They are good quality mcmurdo sockets.

[@stevebrown4085]

Hummmmm. Makes me wonder if a cap draining device in the form of a tube socket couldn't be made for those who want to drain and or check the cap voltage without pulling the chassis. It would need some sort of voltage indicator. Just a thought.

[@richardmacphee2367]

How do you find schematics for vintage tube amps? I have a knight stereo amplifier with no model number in it, I’m not finding anything, it was a very week b channel, and these things only had sticker with model numbers, any pointers? Keep up the videos there awesome 😎

[@haroldsparkman6008]

Thanks for info Terry. I will be sure to never do that. Leave it to the pros

[@luckyvr39163]

Can you build me an class a/b tube head

[@waynemarc77]

Terry , Why are your videos so short? you need to make them longer.

[@d-labelectronics]

The Basic Training series is meant to be short. I have longer repair vids also

[@freddycookjr.2164]

SUBSCIBE THERE IS HUNDREDS OF HOURS OF USEFUL KNOWLEGE

[@donstewart368]

How many have been killed by an amp. I would say none. Its not the volts, its the amps.

[@richardcron2395]

I've always felt that finger nails are overrated.