Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: jerrydyer on November 28, 2012, 11:19:57 am
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ever seen brown goo that smells burned come out of a PT. its a 100 watt amp, new company and he is sending me a PT but ??? Ive never seen this. I do notice he has a lot of features and if this pt is the model I think it is its amp rating is a little low for all these bells and whistles.
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That brown goo is either epoxy, enamel, polyurethane, or polyseter winding insulation that has melted because of heat probably caused by an under-rated transformer.......if the circuit is drawing more current than the xfmr is rated for it will heat up and compromise the insulation that is meant to keep the windings separated from each other and ground,,, which presents a potential fire and/or shock hazard.
I personally always use over-rated xfmr's for that reason alone.......guys that try to save a penny in manufacturing should build safer, cheaper things like arts and crafts :icon_biggrin:........a nice potpourri bowl can't KILL YOU..........a new transformer co.?....can
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Some transformers smell, most do. Burnt is not the smell, electric train is. I have seen some transformers leak, but be perfectly fine if they stop leaking. The real question is the transformer getting hot to touch. If so, something is wrong.
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He borught it to me after fuse blew and he said he saw smoke. more than a cigarette smoke. OH IT GOT HOT. I can tell by looking at it. I dont think he thought about the amperage when he chose this PT. anways, he is sending me a new one, hopefully things have been revised and its rated a littler higher. very cooperative but not very fiendly.. I tried to make a joke using "Brown 25 " from the movie groove tube????? he didnt get it. he is canadian. :laugh:
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Hey,Hey! I'm Canadian and I know lots of good things come from Uranus! :l2:
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this guy has zero personality. :dontknow: "brown 25" everyone knows about brown 25.... it came out of his PT. replacement came from ce dist. where do they get em done heybower?
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LOL, I think I saw this as a kid downtown at the ol' Surf Theater way back then? Do you go back that far locally Jerry?
http://youtu.be/008BPUdQ1XA (http://youtu.be/008BPUdQ1XA)
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He borught it to me after fuse blew and he said he saw smoke.
Wait a minute, fuse blew??? Are you sure the transformer is to blame? If the fuse blew, doesn't that suggest the amp was drawing more current that it should have been? So maybe the transformer was trying to supply more current than it it was expected to handle - not more than it was rated for.
If it was just a matter of an underated transformer would the fuse have blown?
If the amp is supposed to draw X amps and the transformer is rated for less then the transformer would burn up but if the amp is supposed to draw X amps and the transformer is rated for X amps but there is something wrong with the amp causing it to draw more than X amps then extra current would overheat the transformer and cause the fuse would blow, no?
I'd double check the amp before throwing in a new Xfmr.