The A470 OPT, an interesting work of art.

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The A470 OPT, an interesting work of art.

Postby Geek » Mon Sep 14, 2009 3:07 pm

Hi Folks,

Of all the things Dynaco may have cheaped out on, the OPT wasn't one of them. It's a work of art!


Winding counts are actual and typical for handwound:

Image


The electrical schematic of the windings. Turns here were averaged and rounded to the nearest 5T, which mathematically is correct for the ratios:

Image



So yeah, that's what I did with my weekend (lol)


Cheers!
-= Gregg =-
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Postby Ty_Bower » Mon Sep 14, 2009 3:14 pm

You unwound one? I wanna see the pile of spaghetti!
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Postby EWBrown » Mon Sep 14, 2009 3:26 pm

Wow.... You must have the patience of a saint...

I'd probably end up tossing the half-unwound tranny through the nearest plate glass window, before I got that far along. (666) (lol)

I have a "dud" Z-565 that I had considered performing an "alien autopsy" upon, but I never had the "drive" to undertake the operation...

It's still kicking around somewhere in the cellar in one of about fifty boxes full of "iron" =:o


Definitely a lot more complex than the usual series wound multiple tapped primary, the paralleled windings and bifilar secondary are what make the tranny so good!

I'd bet a lot that the ill-fated E-bay "Handwound" A470 "equivalents" aren't so artfully crafted. (666) As I recall, the Z- 565 "equivalents" read only 76 ohms per side primary DCR, in stead of the more normal approximately 195 ohms per side. yeah, they were pretty much crap... (sick)

/ed B in NC
Last edited by EWBrown on Tue Sep 15, 2009 10:35 am, edited 1 time in total.
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Postby Geek » Mon Sep 14, 2009 6:03 pm

Ty_Bower wrote:You unwound one? I wanna see the pile of spaghetti!


Yup!

I had to bin it fast, one of the cats thought it was spaghetti (sick)


Wow.... You must have the patience of a saint...


It took some... though the chardonnay took the pain out of it though (wine)

It's still kicking around somewhere in teh cellar in one of about fifty boxes full of "iron"


Lucky guy! (love)


I'd bet a lot that the "Handwound" A470 "equivalents" aren't so artfully crafted.


Well, I sent the info to my custom guy.... if it's economical, we might see some quality equivalents popping up somewhere [:)


Cheers!
-= Gregg =-
Fine wine comes in glass bottles, not plastic sacks. Therefore the finer electrons are also found in glass bottles.
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Postby Geek » Mon Sep 14, 2009 9:07 pm

Hi Ed,

EWBrown wrote:I have a "dud" Z-565 that I had considered performing an "alien autopsy" upon, but I never had the "drive" to undertake the operation...


Would you consider sending the bobbin to me to do the dirty work?

Cheers!
-= Gregg =-
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Postby Yves » Tue Oct 13, 2009 6:19 am

Highly enlighting (y)

Thanks a lot for your efforts ;)

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Postby Geek » Tue Oct 13, 2009 2:45 pm

Hi Yves,

You're welcome! :-)

Rich on diyAudio says it's almost identical to a 20W Philips windup.

Cheers!
-= Gregg =-
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Postby EWBrown » Tue Oct 13, 2009 3:52 pm

I take it that since the GZ got nuked, that the tranny winding images you had posted were also blasted into the vast bit bucket black hole in the center of the galaxy?

FWIW, I still can't get to there from here, I tried just about every known trick in the book...

/ed B
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Postby Geek » Tue Oct 13, 2009 4:03 pm

Hi Ed,

EWBrown wrote:I take it that since the GZ got nuked, that the tranny winding images you had posted were also blasted into the vast bit bucket black hole in the center of the galaxy?


One lousy misdressed primary winding was touching a secondary one and created the "lightning globe" in the wax :-\


FWIW, I still can't get to there from here, I tried just about every known trick in the book...


Does your ISP use caching? It may be hosed.

Can you get straight to the GeeK ZonE OK?
http://geek.scorpiorising.ca/GeeK_ZonE/

How about my pics folder?
http://geek.scorpiorising.ca/contrib/Geek/

You can also try the "backdoor":
http://www.scorpiorising.ca/geek

Cheers!
-= Gregg =-
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Postby EWBrown » Tue Oct 13, 2009 4:29 pm

Nope, nope and nope...

All I get is this : Internet Explorer cannot display the webpage

I tried googling, dogpiling and ixquicking, too, no joy...

/ed B
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Postby soundmasterg » Fri Oct 16, 2009 5:18 am

I thought Triode Electronics had a good clone of these available?

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Postby Geek » Fri Oct 16, 2009 5:33 am

Hi,

soundmasterg wrote:I thought Triode Electronics had a good clone of these available?


They probably do, I've never heard anything not good about them.

BUT... I have something else in mind that Triode can't do ;-)

Cheers!
-= Gregg =-
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Postby EWBrown » Fri Oct 16, 2009 8:35 am

I still have yet to dig up the dud Z-565, it'll come to the surface eventually... I'll remove the endbells to lighten the postal load (and, besides, I need them for covering up another "nekkid" trannie.

(round here "naked" means no clothes, and "nekkid" implies some form of monkey business going on) ;-)

stay tubed

/ed B
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Postby Geek » Fri Oct 16, 2009 2:26 pm

Look forward to the project :-D

Cheers!
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Postby Yves » Sat Oct 17, 2009 12:42 am

Hi Gregg,

Please tell about core size and lams thickness ?

TIA

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