Major missing PT

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xtian
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Re: Major missing PT

Post by xtian »

Thanks for the story, Bob. Fully weird and crazy.

I wonder how Mr. Blackmore felt about repeating his tantrum nightly. "Naw, man, I'm just not feelin' it tonight. Let's just play some CSNY, like?"
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Structo
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Re: Major missing PT

Post by Structo »

Yeah, I'm famous and screw all you f**ktards.

I know it was the rage back then to destroy guitars on stage but it gets to a ridiculous level at some point.

Think of all those kids in Africa that don't get to play a guitar and go to bed every night with visions of Jimi Hendrix in their heads............. :D

What were we talking about?
Tom

Don't let that smoke out!
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Reeltarded
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Re: Major missing PT

Post by Reeltarded »

Umm.. before I go any further, and maybe I am getting a lil over my head early on this..

HOW do I test this OT to see if the PT is missing because this amp is a very old spare that served it's purpose!?

Just on the not so odd chance this thing needs both. ultra linear.. so I found a place that describes checking a different type transformer, but this is a bit different. I am concerned with the orientation of the stand up tranny. It's facing forward, not 90/deg like the other 2 from the same year I can find. My others are slightly earlier, and slightly later. None like this one.. particularly. Man, it's confusing.

Pointers, or maybe someone here would like to take a look at it, and install the new parts if the existing stuff is good to go? Most of the technical information on the web has been gleaned from the same source, and that source appears to be a real ego.. and I think he purposefully misinforms people! No way!

:D
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ToneMerc
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Re: Major missing PT

Post by ToneMerc »

Reeltarded wrote: HOW do I test this OT to see if the PT is missing because this amp is a very old spare that served it's purpose!?
Huh?

TM
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Reeltarded
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Re: Major missing PT

Post by Reeltarded »

Sorry! Half asleep and typin way too fast!

PT is missing. OT is there. OT is 90 degrees out of rotation with pics of other known examples from exact period.

How do I check the OT without power?

I must slow down, and proof-read. So sorry.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
Cliff Schecht
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Re: Major missing PT

Post by Cliff Schecht »

What are you checking for? Proper wiring? If its installed and looks factory I would assume its wired correctly..

With that said, you have to whip out your ohmmeter and start measuring between leads to find a) the primary and secondary side, b) the primary side center tap and outside leads and c) the secondary side ground, 4, 8 and 16 Ohm tap. The primary side will measure about equal between each leg and the center tap. The secondary, if you know where ground is, is as easy as finding the lowest resistance (4 Ohms), second lowest (8 Ohms) and highest. Remember that we are looking at DC resistance though so the measured numbers will be much smaller than the ones said here (which are stated at around 1 kHz usually). It may help on the secondary side to let the ohmmeter settle a bit, the really low resistance readings can take some time to fully resolve.
Cliff Schecht - Circuit P.I.
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Reeltarded
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Re: Major missing PT

Post by Reeltarded »

OT installation appears original, but is turned 90 degrees in orientation when compared against pictures of two known from same time period.

It's installed, so the outputs aren't in question.. I don't know how to check it before I start throwing other parts at the amp.

I have read a simple test might not tell the truth.

I have a pdf of the Mercury replacement, same 5 wire count on the input of the OT, all connected, easy to identify. Whew.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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M Fowler
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Re: Major missing PT

Post by M Fowler »

Maybe the PT that is missing was oriented 90 degrees from what your other two amps are?

In that case perhaps that changed the orientation of the OT?

All things to ponder. Anyhoo when you get the replacement PT you can decide the direction new PT will be bolted in.

Mark
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