Article - Sony VFETs part 1

[buzzforb]

funny transformer thingies

 

[Zen Mod]

now you know why I'm hysteric , all the time

 

[Michael Rothacher]

Lol! Yeah, they're tricky.

When you look at the spec sheets, be sure to look at the number of windings, and when they give a ratio you have to see if they're specifying it for series/series, parallel/series, etc.

 

[dady]

JT-112-LCF JT-11-FLCF - Datasheet Archive


1:2 CONFIGURATION LINE OUTPUT TRANSFORMER QUADFILAR WINDINGS M M M M M Distortion 0.032% typ at 20 Hz and +4 dBu output level



JT-112-LCF JT-112-LCF 1:2 CONFIGURATION LINE OUTPUT TRANSFORMER QUADFILAR WINDINGS M M M M M Distortion 0.032% typ at 20 Hz and +4 dBu output level Wide bandwidth: !3 dB at 0.27 Hz and 370 kHz Drives 600 S loads to levels up to +21 dBu at 20 Hz Excellent time domain performance: DLP 0.3E typ 20 Hz to 20 kHz E Loading loss only 1.5 dB when driving 600 S load This transformer is designed for use as a 1:2 step-up for line output stages operating from low voltage rails. For 1:1 applications consider the JT-11-FLCF JT-11-FLCF. The 50% nickel core alloy has excellent level handling and low distortion.

 

[dady]

JT-11-FLCF does the right transformer?

 

[Michael Rothacher]

Computer says no.

https://www.youtube.com/watch?v=WOdjCb4LwQY

 

[Michael Rothacher]

I just spoke to the very nice people at Jensen and they are going to do a run of the transformers. They asked me to let you know that the JT-112-LCF has been re-numbered and will now be called the JT-123-FLCF, which is just the wire-terminated version of the JT-123-FLPCH, which NP used in the F6 project. So, the two are interchangeable, just terminated differently.

 

[Michael Rothacher]

The take-away here is "four identical windings". I've seen a model or two mentioned in this thread that only have two windings.

 

[Michael Rothacher]

The transformer should look something like this:

 

[dady]

JT-11-FLCF is the right so. Quadrifilar 1 to 1.

 

[Michael Rothacher]

@dady:

I see four wires sticking out of it. One primary, and one secondary. Am I looking at the right one?

And, may I (just out of morbid curiosity) ask what's wrong with using parts that have been specified?

 

[WalterW]

"with primaries in parallel"

You are right, should have looked better at the datasheet....
Not just a quick browse 😱

Walter

 

[Michael Rothacher]

No worries, I think we're mostly back on track. 🙂

 

[Dennis Hui]

I've opened up a thread to better guage the interest of a GB:

http://www.diyaudio.com/forums/grou...ansformers-sony-vfet-project.html#post3869493

Thanks,
Dennis

 

[Soundhappy]

Thanks Dennis for constructive thinking 🙂

 

[Michael Rothacher]

JT-11-FLCF is the right so. Quadrifilar 1 to 1.

JT-11-FLCF is not right.

Quadfilar, yes.

 

[dady]

I mean JT-112-FLCF.
Am I illness by dyslexia?
Quadfilar is enough number of windings?
Thanks Michael and good night, at least we have a defined goal.

 

[Michael Rothacher]

Yes, I think we're on track.

The JT-112-LCF (which is marked JT-112-L on the tape) will soon be known as the JT-123-FLCF as Jensen informs us they'll be renumbering it in the near future. It's just a matter of wire termination vs. PCB pins. I'm sure they will understand what is intended should anyone order the old part. For those building a PCB, the FLPCH is the applicable part.

Good night. 🙂

 

[buzzforb]

Were we off?

 

[Michael Rothacher]

I don't understand the question. Can you give me a little more to work with, Buzz?