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  #1  
Old 4th February 2012, 09:18 PM
Guy Pettigrew Guy Pettigrew is offline
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Default Just found these in a drawer. ?PreII OPTs?

While hunting for something else these two beauties turned up at the back of a drawer.

They are probably output transformers from my old PreII, but they may not be!

Whatever they are, I vaguely remember wrapping the silver adhesive tape round them to minimise hum, or something!

They have D8773 and 5/03 handwritten on them.

Are they worth trying to sell?

Guy

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  #2  
Old 4th February 2012, 09:43 PM
audiopete audiopete is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

If intending to sell on, I could well be interested.

Currently got a elma 24 way switch and have pre-amp build lights going off in my mind.

PRE II specs - Used in our pre-amplifier module, the PREII. Secondary:primary ratio is 6:1, so is a step down transformer. High quality, excellent for driving long interconnects. Maximum current is 15mA, can be used with a 6922 valve (one triode section only). It measures 80mm(w) x 60mm(l) x 65mm(d).

Last edited by audiopete; 4th February 2012 at 09:51 PM. Reason: specs
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  #3  
Old 4th February 2012, 11:53 PM
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Ali Tait Ali Tait is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

They look very like Pre 2 trannies.
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  #4  
Old 5th February 2012, 10:21 AM
John Caswell John Caswell is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

They are indeed Pre II optxs and if used will require the specified Zobel network on the output side to reduce the ringing. Keep far away from other power txs as they were VERY susceptible to magnetic field pickup

John
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  #5  
Old 5th February 2012, 11:12 AM
Guy Pettigrew Guy Pettigrew is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

Thanks Dr John and Ali tait.

I've just PM'd you, Mr audiopete, as you expressed an interest in them.

Oh, and Happy New Year, everyone!

Guy
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  #6  
Old 5th February 2012, 08:06 PM
audiopete audiopete is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

Hi Guy,

PM'd with additional info for you.
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  #7  
Old 5th February 2012, 09:20 PM
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Shane Shane is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

I'll be interested to see what you do with those. I've got a pair sitting out in the shed waiting for an idea to come along.
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  #8  
Old 5th February 2012, 10:57 PM
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Ali Tait Ali Tait is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

This perhaps?

http://www.world-designs.co.uk/forum...read.php?t=144
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  #9  
Old 5th February 2012, 11:45 PM
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Greg. Greg. is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

Quote:
Originally Posted by Ali Tait View Post
Oooo, Ali, is that a serious suggestion or are you being very cynical?

That FAQ thread was introduced, offering a conversion option on Pre II to remove the original Tx's as for many of us, they were a source of hum. See what John posted above on requirements for a quiet application. For many of us this was not feasible. After building the Pre II trio, initially I felt conned because they didn't enhance my sound whatsoever. At first I converted to passive input which worked but sounded a bit flat but I was later delighted to adopt Neal Gibbon's adaption of the Morgan Jones CF design, especially because it brought the sparkle back into the music. I'm still using and loving it
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  #10  
Old 6th February 2012, 12:59 AM
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Ali Tait Ali Tait is offline
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Default Re: Just found these in a drawer. ?PreII OPTs?

No, not at all! I haven't looked into it, so didn't realise the trannies were no longer used. I don't doubt it sounds very good. Thought about trying it with mine, but have Pre3 now, and am happy with it for now, and it would be a shame to dismantle the 2, it's got a lot of expensive bits in it, so I'll probably sell it.
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