Hi

[ivconic]

Q6, BC327/40 should not get hot at all.
TX coil inductance can vary from 1mH to 2.2mH and in resistance 2.5 to 3.5 ohms.
In case of 1mH; parallel capacitor is 474+473 in parallel.
In case od 2.2mH; parallel capacitor is 224.
R12 200 ohms usually adjusted to 68-100 ohms.
R12 serves there to adjust TX amplitude, when observed on oscilloscope to be clean sinus.
Better to use fixed resistor later when adjusted clean sinus.
I can't imagine why and how Q6 can get hot; is schematic and coil specs are obeyed.
Maybe TX coil resistance is too low and applied voltage is too high?
That's common case at some people trying to "boost" it up on amplitude, hoping for better performances.
There would be no better performances that way. On contrary.

[Carl-NC]

Q6, BC327/40 should not get hot at all.

My apologies, I was thinking PI circuits. Ivica is right, Q6 should not get hot. It probably means the oscillator is not oscillating and Q6 is just dumping DC current through the coil.

[hooby life]

Q6, BC327/40 should not get hot at all.
TX coil inductance can vary from 1mH to 2.2mH and in resistance 2.5 to 3.5 ohms.
In case of 1mH; parallel capacitor is 474+473 in parallel.
In case od 2.2mH; parallel capacitor is 224.
R12 200 ohms usually adjusted to 68-100 ohms.
R12 serves there to adjust TX amplitude, when observed on oscilloscope to be clean sinus.
Better to use fixed resistor later when adjusted clean sinus.
I can't imagine why and how Q6 can get hot; is schematic and coil specs are obeyed.
Maybe TX coil resistance is too low and applied voltage is too high?
That's common case at some people trying to "boost" it up on amplitude, hoping for better performances.
There would be no better performances that way. On contrary.

Hello ivconic your Settings TX ans rx are
TX 517nf,1mh=7khz
Rx 68nf, 14.75mh=5khz
Did this correct ?
Regards

[ivconic]

Hello ivconic your Settings TX ans rx are
TX 517nf,1mh=7khz
Rx 68nf, 14.75mh=5khz
Did this correct ?
Regards

7-7.3kHz, depends on components tolerances.
But SMW will work fine from 6.5 to 8.3kHz with slight adjustments.
Yes, you got those right.

[Ruben2000]

Hello Iconic good work for the contribution of the SMW.
I am just getting started on this MD and I am mounting all the components on the PCB; but I would like to ask you several questions regarding the latest publication of the PCB.

[Ruben2000]

First I would like to know why you added this resistor and the connections?

[Ruben2000]

Second, on its PCB and on the Lay I put two 100K resistors but in the diagram they are 10K.

[Ruben2000]

For the coils it is very important that TX is 1mH and RX 15mH?