Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Solid State => Topic started by: spunko on July 28, 2022, 10:42:48 am
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Hello friends. Basically what the tittle says.
The Fatso was working well for years, then one day it felt like "weak" like it lost gain, then the fuse blew. When opened I noticed the transformer melted.
I ordered a new one from amazon, installed and everything seems fine, but I noticed the new transformer gets very hot after 30 minutes of use, so I turned it off again because I'm afraid this trafo will melt too.
Is there any component that can push the trafo that hot? Like the EMI filter beofore the power cord, or the brigde rectifier after the trafo?
(https://i.imgur.com/fvBw3Ca.jpg)
(https://i.imgur.com/JKTVRWm.jpg)
(https://i.imgur.com/SSxaT5F.jpg)
(https://i.imgur.com/6sVZR6Z.jpg)
(https://i.imgur.com/JONQsDX.jpg)
(https://i.imgur.com/r5tYkK0.jpg)
(https://i.imgur.com/sdhgE3Q.jpg)
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that's a rabbit hole i wouldn't venture down :laugh:
since all the major components are "redded out" there probably is no schematic, with the level of complexity and no schematic, shot gunning is a waste of ammo.
I you have a temp probe, use it maybe the current sucker will show up.
any power transistors mounted on chassis?
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Yep, I haven't found a diagram and I'm just lost. No transistors mounted on chasis, all in PCB.
The unit powers and sound great, at least for my ears, but that transformer temp worries me.
EDIT: I forgot to mention that the fuse blew with the old melted transformer, but not with the good one.
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Check those 2200uF caps for shorts or leakage?
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Any heavy load on the PT, such as large leaky caps, will itself get hot. So a close nose or careful finger may lead to a culprit.
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Any news?
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YES! I replaced the 2 big caps and the 4 diodes and now the transformer just feels warm, not hot at all =)
I will keep looking if it gets hot eventually, but so far so good.
It took me this long because I was in the hospital with kidney problems =(
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First, I hope you're feeling and doing better.
Apologies if there was any impatience implied only part.
Glad to hear that the transformer problem seems to be cleared up.
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Thank you very much, I'm much better now. I think God, the universe, or whatever is out there wants me still alive. I suffered a cerebral trombosis a year and a half ago, while been infected by dengue, sound crazy right?. Doctors couldn't use anticoagulants for the trombo until the dengue process have ended (could lead to hemorrhagic dengue), so I stayed in ICU under morfine and other stuff. I don't remenber anything until I was in a room with no dengue and anticoagulants treatment. Two months later I got covid and I wasn't vaccinated because of the trombosis risk as side effect of the vaccine. After all that, I'm standing like nothing happened, the only side effect that remains (which is horrible), is that I get heavy migranes pretty often. Now I have to take care of my kidneys too. I think I don't age well like wine :l2:
Sorry for the long message and private story, I know you don't need to read that, perhaps this is one of the many ways I express my gratitude to the universe :worthy1:
On the other hand, I will keep an eye, or a hand, on the transformer.
Thank you very much for the help. Sorry for the bad english.