Sunn 200S PT and AC chord

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MysteryFever
Posts: 37
Joined: Wed Mar 30, 2011 4:10 am
Location: Maine, USA

Sunn 200S PT and AC chord

Post by MysteryFever »

Just picked up an old 200S for free from a bandmate, he's got two identical heads and this one has been scrapped for parts. I've got a replacement OT on the way since the original is missing, but when I hooked up a three prong AC and fired it up, the fuse blew.

Below are a couple pictures of the chassis. The first is a complete working amp that I've been gigging with. Second is the one I'm working on. Note that the one that works has a two prong chord. Everything seems fine, so my question is this; Do I have a bad PT? Any help is much appreciated, and If you see anything else that could be wrong have at it!
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MysteryFever
Posts: 37
Joined: Wed Mar 30, 2011 4:10 am
Location: Maine, USA

Re: Sunn 200S PT and AC chord

Post by MysteryFever »

Aaaand I just noticed that the bus going from the top lug on the power switch to the polarity reverse switch needs to run not from the pt primary lug but from the neutral ac lug. fixed it, fuse still blows.
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Structo
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Location: Oregon

Re: Sunn 200S PT and AC chord

Post by Structo »

Is the rectifier tube good?
Tom

Don't let that smoke out!
MysteryFever
Posts: 37
Joined: Wed Mar 30, 2011 4:10 am
Location: Maine, USA

Re: Sunn 200S PT and AC chord

Post by MysteryFever »

I tried the gz34 from the working one and still no go. After some more fidgeting and a couple blown fuses today, I unhooked all the secondaries and powered up. Fuse blew again so I'm certain that I have a dead tranny on my hands. They sell a direct replacement at the triode store for about a hundred bucks, but in the meantime, I've begun ripping the old one apart to use as somewhat a learning experience. I've been diagramming it's construction along the way in case I can actually re-wind it myself.
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Structo
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Location: Oregon

Re: Sunn 200S PT and AC chord

Post by Structo »

Did you measure the resistance of the primary and compare that to the other one?

That is cool you have two of the same amp, it would really help troubleshooting and comparing the circuit to make sure it is correct.

Good luck.
Tom

Don't let that smoke out!
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selloutrr
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Re: Sunn 200S PT and AC chord

Post by selloutrr »

My Daughter Build Stone Henge
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