Aquasound

[kt315]

thats wert9 wrote me with the pics he sent.

срочно нужно оживить катушку от Наутилуса, там на схеме вроде был нарисован блок встроенный в катушку. Он там сложный оказался, 2 транзистора 4 емкости и покрайней мере 3 резистора, так вот проблема терь с номиналом емкостей, никак маркеровку понять не могу((((((((

На схеме не указаны транзисторы, они 2n5088. Схема на наутилус без ручной балансировки катушки, у меня с ручной, так что номиналы резюков и кандеров отличаются.

Замерил диаметр проводов в катухе и сопротивление:

ТХ и СХ имеют по 4.2 Ом, толщина провода 0.45мм - одна пара хвостов соединена вместе и кинута на землю, вторая пара на платку в параллель им пленочный кандер неизвестного номинала ( не выпаивал его из воска, так и остался в обойме)
РХ имеет сопротивление 26 Ом толщина 0.3 мм, в параллель РХ стоит кандер 22Н.

TX and CX are 4.2 Ohm each, wire thickness 0.45 mm - one pair of tails connected together and thrown to the ground, the second pair on the (preamp) board, in parallel to them with a film cap of an unknown value (did not solder it from the wax, and remained in the cage)
The PX has a resistance of 26 Ohms with a thickness of 0.3 mm; in parallel with the PX there is a 22nF cap.

Корпус катушки изнутри промазан графитом (напыление), и обе половинки корпуса.

[dbanner]

The Nautilus dmc2bA had an automatic feedback tuning circuit instead of those pesky multi turn feedback pots. It was in the form of an add-on PCB to the dmc2b. I wish I knew the circuit for that upgrade.

[dbanner]

Yes, Im agree with You.

Thanks for your keen observation, I don't think I could have figured it out from those photos.

Now I feel confident I can replicate the original coil.

I think all parts of the puzzle are now in place for a successful project. Now I will compile a project file with all the info, parts list, schematic layout, hardware, coil data etc., etc.

[Altair]

I think I've got it right now. Please follow me.


The red and green wires you labeled as buck minus (-) and buck+, is actually the buck coils ground wires. They are connected to same spot on PCB.

The two ends of the buck coils are connected to the two TX ends in a place not visible from the photo.

You see, we are dealing with a bifilar coil!

Hence the green an red wires, look at the tx wires, green and red, which means two separate windings. Now where are the other ends of those tx windings?
Ah dr.watson.....they are connected to the two ends of the buck coils( a green and a red, hidden from view. Case closed.

A bifilar coil.

The trace out from the guy who opened the coil was improperly done, I don't think he fathomed such a coil. Hence the confusion.

Yes, Im agree with You.

[dbanner]

Altair, looking again at your drawing, you are correct. So you figured it out it's a bifilar coil.

[Altair]

Something still looks wrong. For example, if you follow the foil trace on the small PCB, then it seems that buck minus(-) is connected to one end of the RX coil. This cannot be right.
With the exception of the feedback pots, the buck coils and RX are electrically isolated from one another.

Yes, you rigth.
Seems me the coil is wired differently to Aquasound schematic.
Anyway is clear for me that the two 10 ct 10 windings are bucks.
I have modified the picture.

What's even more strange, the wires you labeled as buck+ and buck-. Are both soldered to the same spot. Zoom in and you will see another wire.

No, are "GND Buck+" and "GND Buck -" that are soldered to the same GND spot. This is correct. The another wire is green and more thick respect to RX wire; it could be for connect the shield.

[dbanner]

I think I've got it right now. Please follow me.


The red and green wires you labeled as buck minus (-) and buck+, is actually the buck coils ground wires. They are connected to same spot on PCB.

The two ends of the buck coils are connected to the two TX ends in a place not visible from the photo.

You see, we are dealing with a bifilar coil!

Hence the green an red wires, look at the tx wires, green and red, which means two separate windings. Now where are the other ends of those tx windings?
Ah dr.watson.....they are connected to the two ends of the buck coils( a green and a red, hidden from view. Case closed.

A bifilar coil.

The trace out from the guy who opened the coil was improperly done, I don't think he fathomed such a coil. Hence the confusion.

[dbanner]

[dbanner]

Something still looks wrong. For example, if you follow the foil trace on the small PCB, then it seems that buck minus(-) is connected to one end of the RX coil. This cannot be right.
With the exception of the feedback pots, the buck coils and RX are electrically isolated from one another.

[Altair]

After watch Nautilus coil Photos, I have marked the wirings inside coil. For shure the two 10 ct 10 windings are bucks. See my attached draw.

[dbanner]

https://m.youtube.com/watch?v=vcSbD59HueE&t=300s

https://m.youtube.com/watch?v=FBWhSnMOBt0

[dbanner]

Although the mutual inductance is opposing, I expect that the effect is small, 50x50 turns will get you roughly a little more inductance than 40-10-10-40 buck coil arrangement.

But this is inconsequential, as the RX coil must still be balanced close to full resonance. Don't matter if the TX frequency is 51kHz or 49 kHz. You can tweak the tuning cap value to resonate the coil to 50kHz if that is your goal.

[Altair]

dbanner,
buck coils must wounded in opposite way respect to TX coil so, if 10-10 windings are for bucking, the total inductance of 40-10-ct-10-40 should be less then 50-ct-50 of a corrisponding DD coil.

Kt315,
thank you for share photos.

From photos I note some different components values regarding preamp between Nautilus and Aquasound schematic.

[kt315]

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[kt315]

nautilus coil