Altec 1592A Mixer Output Transformer

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CJ

Well-known member
Joined
Jun 3, 2004
Messages
16,114
Location
California
Got this in the mail, thanks!

Looks like a pentafillar wound coil on a sq stack of 375 EI

So of course 1:1 ratio primary to secondary

1:1 ratio primary to feedback

5 strands of 34 AWG
0.007" red and green, scatterwound at the same time,

PRI DCR 30 ohms each coil

Green former and lead plate all as one, indicates Peerless

PRI Ind 12 Henrys at 50 Hz (one PRI)

Saturation at about 6 Vrms
(1 PRI)
Looks like an easy rewind if I can get the core apart.

Pentafillar wound means no worries about phase between primary and tertiary winding, the capacitance is high but balanced. Similar to API output.

Pics and print coming up...
 
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some pics of the Altec transformer,

they used an epoxy so the lams could not be taken out without destruction, no matter how hot,

and that former will melt if you get it real hot,

but now i can get the turns,
 

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got the coil unwound which was not easy as the outside layers of wire were breaking due to the coil being processed with epoxy.

the inner winds came apart fairly easily with the heat gun, 5 strands to pull on at once

here is a prelemiunary print before the rewind, the turns count might go up or down depending on how full the bobbin gets with #34 AWG.
 

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got this thing rewound, 525 turns #34 did the trick, same fill %, same DCR,

tried new nickel lams but the old ones, even after getting beat up during dis-assembly, seem to match up with the new, so those were used and these lams saved for something else,

#20 AWG buss wire JB welded into the holes instead of square posts which just get smashed into the former and epoxied during processing.,

had two different colors of #34, red and redder,
 

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tests out just like the API quad-filar output, capacitance takes over gradually, extending the response out to 1 Meg,

no phase shift, which is good for the F/B wind,

dual trace, input vs output
 

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I measured the turn length of an outside wind in inches and multiplied by 550. Then divide by 12 to get feet, measured the turn length of the empty bobbins etc, then spooled up some bobbins with that length and a few more feet jic.
 
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