How to receive multiple frequencies simultaneously through a sub1ghz chip?

[pdskill]

I have a remote control that can copy multiple frequencies, such as 433 MHz, 315 MHz, or other frequencies. When I disassembled it, I found that the main control chip and the RF chip were polished, so I couldn't identify the model through the markings. However, by examining the package, crystal oscillator, and the distribution of external capacitors and resistors, I deduced that the RF chip is a sub-1GHz chip produced in China with the code name CMT2300A. How is it possible to use a sub-1GHz chip to simultaneously detect multiple frequencies and copy signals from remote controls of various frequencies?

[shabaz]

Curious why the photo has silkscreen labeling hidden by you. What's the reason? Secondly, do you require the information for a legal purpose? Given that it looks like a device for rolling codes.

[radiolistener]

How is it possible to use a sub-1GHz chip to simultaneously detect multiple frequencies and copy signals from remote controls of various frequencies?

This is very easy, just use several frequency down converters feed with different frequency and get as many simultaneous frequency reception as you want.

There is also more simple and cheap way, just scan several frequencies every 0.1 sec and when a carrier is detected on one of the scanned frequencies, simply start recording it. In that way you can done it just with one mixer.

[tggzzz]

Curious why the photo has silkscreen labeling hidden by you. What's the reason? Secondly, do you require the information for a legal purpose? Given that it looks like a device for rolling codes.

Precisely.

The near-duplicate posting is also suspicious https://www.eevblog.com/forum/beginners/a-question-about-the-implementation-of-multi-frequency-copy-remote-control/msg5573751/#msg5573751

[pdskill]

Curious why the photo has silkscreen labeling hidden by you. What's the reason? Secondly, do you require the information for a legal purpose? Given that it looks like a device for rolling codes.

Precisely.

The near-duplicate posting is also suspicious https://www.eevblog.com/forum/beginners/a-question-about-the-implementation-of-multi-frequency-copy-remote-control/msg5573751/#msg5573751

This is my first time using this forum, so I don't know which section to post to.

Curious why the photo has silkscreen labeling hidden by you. What's the reason? Secondly, do you require the information for a legal purpose? Given that it looks like a device for rolling codes.

Precisely.

The near-duplicate posting is also suspicious https://www.eevblog.com/forum/beginners/a-question-about-the-implementation-of-multi-frequency-copy-remote-control/msg5573751/#msg5573751

[pdskill]

How is it possible to use a sub-1GHz chip to simultaneously detect multiple frequencies and copy signals from remote controls of various frequencies?

This is very easy, just use several frequency down converters feed with different frequency and get as many simultaneous frequency reception as you want.

There is also more simple and cheap way, just scan several frequencies every 0.1 sec and when a carrier is detected on one of the scanned frequencies, simply start recording it. In that way you can done it just with one mixer.

If I only use one, how should I ensure that every transmitted frequency can be received? I have tried the method of cycling the frequency, but it cannot guarantee that every transmitted signal can be received.

[tggzzz]

Curious why the photo has silkscreen labeling hidden by you. What's the reason? Secondly, do you require the information for a legal purpose? Given that it looks like a device for rolling codes.

Precisely.

The near-duplicate posting is also suspicious https://www.eevblog.com/forum/beginners/a-question-about-the-implementation-of-multi-frequency-copy-remote-control/msg5573751/#msg5573751

This is my first time using this forum, so I don't know which section to post to.

Double posting is always annoying, on any forum, and has been for the past 40 years.

Do you have any responses to the questions from shabaz?