Aquasound

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Deleted

[Altair]

I am busy with schematic revise: draw is completed, check components value to be terminated.
Schematic of existing pcb will ready soon.

[Altair]

Here schematic (rev 1) related to the available photos from KT315:

[jasonNZ]

What transformer is being used on this pcb ? I would like to try source them.

[Altair]

What transformer is being used on this pcb ? I would like to try source them.

jasonNZ,
the trasformer should have the following spec:
ratio 1:2+2;
primary: 25 Ohm
Secondary: 50 + 50 Ohm

I don't know more.

[kt315]

sorry, output transformer. it transforms a voltage in a current. then primary would be more, secondary less.

[dbanner]

Audio output transformer from junk pocket transistor radio, you can find those.

[kt315]

yup, also can take any ferrite ring and wind 150-200 plus 20-50 wire loops. on secondary take 0.4-0.7 diameter wire.

[dbanner]

SLB (search loop balance) pots are ordinary 100k linear potentiometers. "R" and "C".

[dbanner]

Coil must be set at 0 degrees phase, very important when making the coil.

(According to the patent) "the coils are adjusted for 0 degrees phase shift of an impressed test signal from the tx coil, as received by the RX coil."

That's fancy language for saying that the coils are balanced by phase and not by minimum residual voltage.

[dbanner]

Here again I'm reminded of tesoro coil balance by phase and not minimum residual voltage.

[dbanner]

However there is one caveat. No mention is made of whether the RX is tuned or left untuned while balancing for 0 degrees phase shift.

I ask this question because I know phase shift is frequency dependent, is it not?

So is it 0 degrees tuned or 0 degrees untuned?

Given the fact that this detector has feedback adjustment pots for both voltage and phase, I think the 0 degrees phase shift is with the tuning capacitor. But I'm not certain.

[dbanner]

Thinking about it some more, perhaps it's simply balancing the RX coil without any tuning cap, just naked, and looking for 0 degrees phase shift directly from the RX coil to the scope.

[kt315]

my mistake. this transformer is for piezo element, not for a speaker connection . so secondary part has more winding, because piezo 'needs high voltage'.
first issue is RIGHT.
http://kamrad-club.ru/-razdel-master....html#comments

[Altair]

I have rougly calcutated the coil inductance starting from Nautilus Patent:
TX: about 1500 + 1500 uH (with bucking reduction);
RX: about 4000 + 4000 uH.
Now a coil with different diameters can be calculated.