Cinemag Custom Input Winston O'Boogie

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CJ

Well-known member
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Joined
Jun 3, 2004
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Location
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John Hinson sent me this custom ratio input he had made from Cinemag.

It is for the Redd 47 or UA610, works for either one.

I have some similar units in a Melcor amp that sounds great.

What is the magic ratio? How is it wound? Lets find out. Here is a unit already installed

it is a slightly different model due to the wire colors, i wanted it for a pic as i ripped the case off ,,

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son of flubber potting compound pops apart under heat, very easy and clean compared to black tar,

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don't even have to rip it  for structure, this is an input, so we expect many turns on the sec,

see the two big windings? those must be the 2 sec's.

see the small pri linked tight to the core? that must be a pri, so just by lookin and thinkin a bit,

we can hedge a bet for Pri Sec Pri Sec Pri,

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so every time i open up an xfmr, i see something new, different, interesting, weird, or exciting.

this guy was something totally un expected. i remember John telling me about his "secret" ratio.

well, his handle is Winston O Boogie. Winston is John Lennon's middle name, so what?

here is where it gets a little spooky. Hinson was a Lennon FREAK. When was John Lennon born?

1940.

How many turns on the two secondary windings?

1940. 

OK then.

what else was weird?  the primary winding has 3 parallel windings. all 570 turns.

the inner two windings are reversed, never seen parallel input windings,

never seen the two inner reversed, usually it is the center winding that is reversed.

so either somebody screwed up which is why i got them cheap, or JH orderd some weird stuff.

anyway, the turns go 3,880/570 =

1 : 6.8

  seems like a cool ratio, right in between the 1:8 and the 1:5.5, not a common ratio at all.

so the impedance ratio is about 1 : 45, so if you have 600 ohms on the input, the sec will have

an enviroment that feels like about 45 * 600 = 27 K.

Structure:  P-S-P-S-P

Wire:  Pri:  # 38  Sec: #42

i will write this sucker up.
rock over London, Rock on Chicago.  Spartan Dodge, where the Price Slasher lives.


 
I got a few of these from John, too.  I think this eventually became the CMMI-7C. 

http://cinemag.biz/mic_input/CMMI-7C.pdf

Thanks for getting your hands dirty CJ.  You're on a roll...  err...  turn.
 
So essentially, because one primary is connected in reverse, it cancels out one of the other primary coils? Its basic function is to split the secondary into two sections for less distributed capacitance, I suppose?
 
if you swap the start and finish of a reverse wind, then you will not cancel.

if you leave the starts and finishes the same, they coils will cancel, and this would be a dead short.

maybe not, sounds like an experiment is in order?


i'm still tripin on the 1940 thing,  :eek:


Miko, thanks for the 411!

 
yes, now i remember! cool.

ok, i changed the Z to 200 ohms and flipped the colors and added start/finish. etc

so the 9 K sec Z makes more sense than 27 K.

they want to drive 97 k ohms or some weird number, why don't they just say 100 K load?  :(

thanks to Miko again, this is the Cinemag #7 without the 50 tap, this means more room for turns,



ok, we got a Keyon on the chop block,

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Is there a way to view threads and their contents? Every photo etc has been removed.
 
This is a 14 year old thread. The forum has changed greatly in that time, including many large technical backend changes that have significantly affected where and how media shared on the forum is hosted. It appears that wherever those pictures lived, they are long gone. A shame, but not uncommon in these older threads.
 
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