Are there still applications for AM DSB-SC system?

[KerimF]

Hello,

I am new here.
So, I apologize in advance if such a topic is not related to this forum.

I guess most of you know already that the two main drawbacks in transmitting voice/info by using the RF system of double side band suppressed carrier (DSB-SC) are:
[1] Its effective/needed bandwidth is twice of the SSB-SC one.
[2] The receiving circuit is more complex than in case of SSB-SC.
There may be a third drawback (though not clearly confirmed yet, speaking practically) related to S/N ratio.

On the other hand, we may say that the main advantage of DSB-SC could be seen in its transmitting circuit which is simpler than of SSB-SC.

May I ask two questions?

[Q1] If the demodulator of the DSB-SC signal is made to be simpler (cost-effective) and more reliable (practical) than of SSB-SC, do you think there could be simple or commercial applications for it?

[Q2] If such a simple reliable DSB-SC demodulator (with a lock range around the suppressed carrier) cannot be found in the university’s libraries, don’t you think it is good/worth to add its topology as an academic idea, in the least?

Thank you.
Kerim

 

[KerimF]

By the way, a DSB-SC demodulator is said simple if:
1. It hasn’t I-Q signals (in quadrature), as in Costas Loop.
2. And it hasn’t a selective LC filter (a coil), as in the Squaring topology.
3. Also, the values of its resistors and capacitors don’t have to be precise.
4. Its ICs are low-cost standard ones.
5. If necessary, it can be made as a low-cost integrated circuit (IC).

It is said reliable/practical if:
6. It is a synchronous detector that doesn’t have the limitations of a diode detector.
7. It locks to the frequency of the suppressed carrier even if it varies, deliberately or not (due to temperature for example), in a relatively wide spectrum.

 

[Delta Prime]

I guess most of you know already that the two main drawbacks in transmitting voice/info by using the RF system of double side band suppressed carrier (DSB-SC) are:

You guessed wrong!
Aren’t you the one while working on your thesis in (1979),you had the idea (it was before the last one) to recover the original audio amplitude by inverting the demodulated one at the appropriate crossover points of the DSB-SC.
What a joke!
Empirically you are a troll.

 

[KerimF]

You guessed wrong!
Aren’t you the one while working on your thesis in (1979),you had the idea (it was before the last one) to recover the original audio amplitude by inverting the demodulated one at the appropriate crossover points of the DSB-SC.
What a joke!
Empirically you are a troll.

Hi Delta,

Yes, I am the one who had the chance to build, in 1979, a simple DSB-SC demodulator. But it is based on PLL, not by inverting the demodulated signal... etc.

The one, you mentioned, was patented by someone else and it is not based on PLL. So, it doesn't lock to the frequency of the suppressed carrier as mine does.

I wonder why you were confused. Unfortunately, we, the imperfect humans, cannot avoid misunderstanding each other once a while.

Cheers,
Kerim

 

[Delta Prime]

we, the imperfect humans, cannot avoid misunderstanding each other once a while.

Speak for yourself human or ugly bags of water. Post your schematic!

 

[KerimF]

Speak for yourself human or ugly bags of water. Post your schematic!

Sorry, I seldom talk to a perfect human (a perfect AI robot?).

I liked the description you gave: "ugly bag of water". This is the first time I hear it, thank you. And you followed it by 'an order', as in the army. Yes, it is an amazing situation; ‘an ugly bag of water’ is commanded by a perfect non-human master to do something.

After all, you have no real interest to see the schematic of my simple reliable DSB-SC demodulator, for two reasons:
[1] You know my work already from the same site you discovered that I did it (its basic version) in year 1979.
[2] You didn’t give any serious answer, positive or negative, to the thread’s question.

Finally, after hearing your two warm welcomes, I expect I will be banned soon if you own this forum. And I will have no reason to blame you. In these days, a perfect AI robot is not supposed to talk to an imperfect human.

 

[KerimF]

Subterfuge!
Post your schematic…

A new word to learn, thank you. I am looking for the meaning of 'subterfuge'.

 

[KerimF]

I wonder why you insist asking me to break the rule (even as an order, after you called me a troll)!
The schematic is off topic here. It doesn’t answer the thread’s question.

It could be the topic of another thread though, for example a thread whose title is like ‘Which is the simplest reliable DSB-SC demodulator?’

 

[Delta Prime]

The schematic is off topic here. It doesn’t answer the thread’s question.

I recognize the importance of an electronic schematic.
A schematic says more than anything else, in an electronic circuit.
Generally speaking; at minimum I wind up being as precise as I need to be, or at maximum as precise, as I can be…

 

[Delta Prime]

To the moderators who deleted my post! You might as well delete said Quote as well!
You don’t tidy up very well do you?
After all, everyone learned something of this thread.