Building Wolf Treasure [Tesoro Lobo]

[Ruben2000]

Also, in post 28. Again, test point B (a different B).
As KT315 pointed out, that "square" wave is looking lopsided, agree?
Supposedly, we have gotten past that ugly waveform, because otherwise, you would probably not have a nicely symmetrical, low distortion sine wave at point A.
SO, what is the story? Please do not overlook important details or you waste everybody's time.

Check again, using the high dollar scope. That should be a 50-50 square wave, or at least have almost immeasurable deviation from being square.

Thanks for your rolling rock advice.

Is it necessary for the output signal to be 50% high and 50% low at 555 pin 3?

[Ruben2000]

Sir Ruben, how It's going? Your PCB looks good the component very convincing, the coil part, how many coil you have? I make five coil mix with my DIP version of vlaser smd origin design. Have you try zoomix coil the one with 28mh RX ? The coil making and amplitude adjustment is my worst part as I lack of understanding, but vlaser version the one without static channel are simplest

Hello op04!
I only have the coils that I made the ones mentioned in message # 25.

What is the Vlaser version you are building?
Could you upload it to the thread, maybe I would encourage myself to build it?

I have not tested the zoomix coil, nor do I know its capabilities. I am new at this.

For me it is also difficult to make the coils and adjust it; You should keep in mind that LCRs and multimeters do not measure equal to the capacities of the coils and capacitors.
For the amplitude according to what you learned is that you should try not to deform the wave in the highest peak, you have to keep a clean sine.

I would like to see your DIP Vlaser version.

[Op04]

Sir Ruben, how It's going? Your PCB looks good the component very convincing, the coil part, how many coil you have? I make five coil mix with my DIP version of vlaser smd origin design. Have you try zoomix coil the one with 28mh RX ? The coil making and amplitude adjustment is my worst part as I lack of understanding, but vlaser version the one without static channel are simplest

[rolling rock]

Moving right along... I must have been seeing thing.

Where I come from they call it... OPTICAL ILLUSIONS!!

[kt315]

in our language MEANDER is the clear symmetrical square signal. in your one i see, i googled, MEANDER has more widely concept, sometimes not 50/50.
ok. if we take a full period the signal is sure half of it. SURE 50% of full period.

[rolling rock]

Also, in post 28. Again, test point B (a different B).
As KT315 pointed out, that "square" wave is looking lopsided, agree?
Supposedly, we have gotten past that ugly waveform, because otherwise, you would probably not have a nicely symmetrical, low distortion sine wave at point A.
SO, what is the story? Please do not overlook important details or you waste everybody's time.

Check again, using the high dollar scope. That should be a 50-50 square wave, or at least have almost immeasurable deviation from being square.

[rolling rock]

Will the waveforms be okay?

Referring to the picture in post 34, the answer to your question is NO.

What do you have, off the page, connected to point B?? That is supposed to be a square-wave, with slightly rounded edges. What you are showing at B is (was) very bad. I believe you were going to replace your 2N3819 with 2N4393, so, what does point B look like now?

[Ruben2000]

Here i have a picture.

[kt315]

rolling, yup,,, in later circuit same constructor did put a trigger between 555 and tx driver. it gives clear symmetry.
simplest decision. we know this schematic like TROY SHADOW.

[rolling rock]

In post #65, "Analog 5V transmit 20us", that wave is not symmetrical. Just like KT315 told you (in different words), it has to be a LOW DISTORTION sine wave.
Provided you have enough travel on VR2, you should adjust VR2 as you watch the oscilloscope: the wave will increase and decrease as you turn the trimmer. Adjust VR2 for maximum amplitude, then use VR1 to get about 16Vp-p (no more, assuming your transmit supply is +8V). Then, use VR2 again, to make sure of best low distortion possible. Go back and forth, as many times as necessary.
The correct position for VR2 depends on the LC values, they go hand-in-hand.

Fo = 0.159/(square root (LC))
Multi-turn trimpots are really good to have here.

[Ruben2000]

Thank you very much for your rolling rock tips !!
I don't know much about what the wave should look like but I'm going to give it a try.

[rolling rock]

Your transmit signal is not a very clean sine wave, but indicates that the parallel capacitor is not exactly the correct value to resonate at the frequency you have chosen. A very near miss, but could be improved. You should adjust VR2 until the waveform is not obviously distorted. That would be easier than replacing the capacitor, but it's your choice. You will also need to be adjusting VR1 to adjust signal amplitude, back and forth, until optimized signal purity and amplitude are attained.

However, your lack of discrimination is a separate problem.

[Op04]

For 4393 I recommended PN4393 mpf102 or J113 or BF245A look post #3

[Ruben2000]

Here I publish the measurements with the two oscilloscopes, one is the TX signal and the other is the signal from Pin 6 of the 4024.
Are those measurements correct?

[Ruben2000]

check polarity of the diodes on 4024 and their availability.

Thanks KT, the polarity of the diodes is correct.