The rectifier from hell, a little story. - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 27th April 2006, 07:10 AM   #1
diyAudio Member
 
Join Date: Jan 2005
Location: trondheim, norway
Send a message via MSN to Makofoed-6sn7
Default The rectifier from hell, a little story.

Hello,

I though I would tell you a litte story, about a rectifier that weren't feeling to well.

It all started at work, It came in an beautiful Mesa Dual Rectifier. It weren't feeling to well, it's distortion precense were up and power output down.
Trying to cheer him up as best as I could, I started to debug. First of all the output tubes had low emission. Poping in new ones bought that up, but then the voltage droped. Time for some new rectifiers. I pop'd in two new and slowley bought up the voltage on variac. For some reason the voltage didn't come up, but it didn't pull any current so it was safe to debug with full mains on. Then there was a BANG! Were did that rectifier go? The glas was completley gone. And I was a little bit frighten of the result. The rectifier was bad, popping a new one cured everything, but still...
For some reason, I just have to cover my self when I'm testing something with rectifiers...

Hope I scared some of 'u guys with rect. toobs.

Now, has anyone any ide of what that happend? The getter was fine when I put'd in the amplifier.


Best regards,
Magnus
__________________
The line under is true
The line above is false
  Reply With Quote
Old 27th April 2006, 07:40 AM   #2
arnoldc is offline arnoldc  Philippines
diyAudio Member
 
Join Date: Apr 2003
Location: Makati
Send a message via Yahoo to arnoldc
That is something I DON'T WANT to experience
  Reply With Quote
Old 27th April 2006, 09:24 AM   #3
diyAudio Member
 
Join Date: Feb 2005
Location: leeuwarden, netherlands
Quote:
For some reason the voltage didn't come up, but it didn't pull any current so it was safe to debug with full mains on.
that scared me......

strange phenomenon......the voltage didn't come up.....maybe the rectifier was overdissipating way too much, got too hot and imploded?????
__________________
emission over emittor
  Reply With Quote
Old 27th April 2006, 01:57 PM   #4
diyAudio Member
 
Join Date: Jan 2005
Location: trondheim, norway
Send a message via MSN to Makofoed-6sn7
Hi,

That's what scared me too. And IF it was overheating, it should have pull'd some current? No heat without current. The anodes was room temprature when I took it out of it's socket, that was very short time after it blowed up.

And I also chek'd the circuit many, many times before plugging in a new after the imploded rectifier. Very, very strange...

So far to my list of nasty thing at work:

Rectifier implosion: Check'd
Amplifier with pig blood: Check'd
Expolding el.cap: Check'd
Man that says that we are "Finnish'd": Check'd

Funny list...

Best regards,
Magnus
__________________
The line under is true
The line above is false
  Reply With Quote
Old 27th April 2006, 04:37 PM   #5
diyAudio Member
 
tubelab.com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
I have seen tubes with a hairline crack in the glass shatter with no warning. Sometimes the tube will work normally, other times there will be low current, distortion or other effects of air leaking into the tube. Sometimes there will be a blue or pink glow. Often times the crack will be at the bottom of the tube where the base glass was joined to the bottle. On an octal tube this will be covered up by the plastic base.

I have an 833A that works fine, except for a visible crack. I am afraid to use this tube because it operates at over 1KV. There will be a small nuclear meltdown if that tube shatters under power!
__________________
Too much power is almost enough! Turn it up till it explodes - then back up just a little.
  Reply With Quote
Old 27th April 2006, 05:34 PM   #6
diyAudio Member
 
Join Date: Jan 2005
Location: trondheim, norway
Send a message via MSN to Makofoed-6sn7
Hi Tubelab,

Could be, if the crack did open when I put it in it's socket. It was a 5U4. Yeah, there was a lot of glass... If I don't remeber worng it take some time for the getter to turn white. I think you are right.
There was a hairline crack that did open when the tubes were put in it's socket. I didn't notice any sign of gas, but i weren't looking to close. If i did, I guess I would have lost some of my sight by now...

Btw, I think we would love some more frightning testing of 833.

Best regards,

Magnus
__________________
The line under is true
The line above is false
  Reply With Quote
Old 27th April 2006, 10:06 PM   #7
diyAudio Member
 
tubelab.com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
Quote:
Btw, I think we would love some more frightning testing of 833.
No time for such fun in the near future, but I have a large box of 833A's. I will build something big when I have some time, and a whole workbench cleaned off.
__________________
Too much power is almost enough! Turn it up till it explodes - then back up just a little.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
My Three Weeks of Hell from Panda bulgin Everything Else 33 7th January 2008 09:18 AM
Anybody heard about Tarzian Silicon Rectifier for Tube Rectifier Replacement? zxx123 Tubes / Valves 4 21st February 2005 04:02 AM
Phono Socket Hell Pbassred Solid State 5 9th January 2004 12:12 AM
First Gainclone (Hell, first amp...) Llamas Chip Amps 48 19th September 2003 03:47 PM
What the hell is that ??? nar Pass Labs 21 10th May 2002 06:11 PM


New To Site? Need Help?

All times are GMT. The time now is 11:35 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2