Fuse blown at first Powerline Voltage Test [resolved]

CrazyMarc · 3405

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Offline CrazyMarc

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Reply #15 on: August 25, 2018, 06:05:34 AM
Just wanted to let you know the fuse was indeed the issue and now that I've got a new one (and about 19 spares lol) it's measuring 241v no problem.

fullheadofnothing, you are of course completely right; I've built enough computers that I should know to RTFM by now (and what a well written manual it is!) and I apologise for asking questions that I can easily check myself. I took all screws out, fitted them properly and it's definitely good now. I also found my friend had put the lockwasher for the safety ground lug on the wrong side of the screw so I sorted that too (not sure that could have caused the fuse to blow though). I've decided to do things myself and just have my friend do the soldering for me.

Thanks for the help. If I run into trouble I'll update but I'll make sure to RTFM thoroughly first.  :)
« Last Edit: August 25, 2018, 06:09:17 AM by CrazyMarc »



Offline CrazyMarc

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Reply #16 on: August 26, 2018, 10:37:06 AM
Hiya. Got everything wired up, been careful to follow all instructions carefully. Initial voltage tests went fine on page 23, 29, glow test went fine. Resistance checks are being a pain, every single one without a star was fine and within tolerance but I couldn't get any reading from the terminals listed with a star in the manual. Checked over my wiring and joints but I can't see any issue to be honest. Bit stuck for what to do next? Half expecting it to just be my multimeter to be honest but I don't want to proceed without asking here first.



Offline CrazyMarc

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Reply #17 on: August 26, 2018, 10:47:12 AM
Hold for now; was tough to see but spotted a couple of suspicious joints, seems to be working after reflowing. Will move on to voltage steps now.



Offline CrazyMarc

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Reply #18 on: August 26, 2018, 11:25:09 AM
Right, voltages measured good, tubes lit, LEDs on; everything seemed sweet and ready. Literally moved from where I was testing it into my bedroom to get set up and now it no longer works; no glow from tubes, no LED lights etc. Switch was in the correct position ofc so...  Loose connection right? Except we checked over about every joint and component both visually and with a multimeter and everything is looking as if it should work; it just doesn't work. Took back to where it was previously working and still nada. So this time I truly am stumped. Any advice on how to continue? Especially in regard to where a bad connection or something of the like in this circumstance would be most likely to occur?



Offline Paul Birkeland

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Reply #19 on: August 26, 2018, 01:01:23 PM
If nothing is lighting up, your voltage checks will change completely and need to be redone.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline CrazyMarc

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Reply #20 on: August 27, 2018, 08:50:58 AM
Reflowed every solder joint and everything except terminal 9 is measuring correctly. Terminal 9 has the correct resistance value of 2.9k but the voltage is 141v, so considerably higher than 115v.



Offline Paul Birkeland

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Reply #21 on: August 27, 2018, 08:55:06 AM
Can you post the voltages for terminals 1-10?  Can you also post some photos of the build?

141V at terminal 9 means that half the 6080 isn't conducting, which could happen for a variety of reasons. 

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline CrazyMarc

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Reply #22 on: August 27, 2018, 10:45:52 AM
So sorry fellas but after reflowing it seems one wire no longer had a firm hold to the octal socket, made a final reflow (then obviously retook measurements which were *all* within tolerance) and now everything is working, crack is pumping jams.

Thanks for the help and for sticking with me while I did the build. I will be doing the speedball also at some point but for now I just want to get used to the sound of the stock crack, give the tubes a bit of time to come into their own etc.



Offline CrazyMarc

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Reply #23 on: August 27, 2018, 06:22:35 PM
Back again. Amp was working fine for about 8 hours, turned it off a while and went to do other stuff for maybe half an hour. Came back and switched the amp on, as the filaments began to glow up the 6080 tube visibly sparked and there was a loud pop in my headphones. I've attached a picture, in it you can see the two metal rods inside; one rod appears to be burned and this is where I saw the spark. I turned it off immediately and haven't turned it on since; wondering what to do now?



Offline Paul Birkeland

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Reply #24 on: August 27, 2018, 07:09:24 PM
Turn it on and check your voltages.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline CrazyMarc

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Reply #25 on: August 29, 2018, 07:34:32 AM
1. 83v
2. 177v
3. 0v
4. 177v
5. 79v

6. 0v
7. 106v
8. 0v
9. 105v
10. 0v

All within tolerance so I assume it's okay... Maybe the spark was loose particulate or something? Am I okay to plug headphones in?



Offline Paul Birkeland

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Reply #26 on: August 29, 2018, 07:39:11 AM
It could be, or it could be a little residual gas in the tube that needs to cook off.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man