TESORO GOLDEN SABRE

[dbanner]

The diodes that I placed have the denomination ST4148.

could it be Zener diode?

No, I dont think so. It is ordinary diode same as 1N4148?

[dbanner]

Maybe it is bad 220uF cap to ground. On the negative rail you should not see any ac waveform.

[Ruben2000]

Thank you for your appreciation banner, I will change for other elements and see what happens.

[Ruben2000]

hello banner!!
I changed both the capacitors and the diodes for new ones from the store and there were no big changes; I took the measurement and got -7.31v.
I will continue with the next steps. I'll go to block number 4 which is the RX stage and see what happens.

[dbanner]

i am now curious to measure the negatve voltage rail on my home brew tgsl. just for comparison.

[dbanner]

i am now curious to measure the negatve voltage rail on my home brew tgsl. just for comparison.

I just measured the negative voltage supply(rail) on my tgsl. It sits at -6.14V. This is more in line with what the schematic of the voltage inverter should derive.

That is with the whole circuit connected and operational.

The -5V on the schematic is wishy washy

[dbanner]

[Ruben2000]

hello banner!
I also opened my non-discriminating TGSL and took the measurement at the -5V point and got -6.5V.

[Ruben2000]

I don't know why the photos are coming out inverted.

[Ruben2000]

hello banner!!
This time I placed all the components of block number 4, also placing the IC U107 (LM35; now being loaded I took the measured at the point of -5V and got -6.35V.

[dbanner]

Load will drop the voltage of the negative rail. Me being kitchen table engineer, I can get this.

But I still don't know why the schematic should insist on -5V, especially when nobody will ever measure anything approaching -5V in reality.

I don't know where they came up with that figure. Perhaps it is meant to infer a minimum voltage.

[waltr]

The charge pump circuit used to create the negative Voltage is not regulated and dependent on components and loading.
Anywhere between -5V to -8V will work to power the op-amps.

[Ruben2000]

Hi friends!!!
I am in the RX stage, I placed a 15nf capacitor in C6 (measured 14.99nf) according to the calculation I made to be able to obtain 16.12KHz (non-resonant) with an Rx inductance of 6500uH. I put it on the oscilloscope and I want to know your opinion about it, here I put the image: It is at 20uS, 5V (higher is TX).
20uS, 0.1V (bottom pin7 U101a).

[Ruben2000]

This is another image where the coils are very close to the null point and the RX wave is deformed.

[mostafalesnar91]

Is this cable suitable ??? And that it should be a few meters