Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

does any one uses LM567 tone decoder..??

Status
Not open for further replies.
A

aliraza786

Full Member level 4
Joined
Nov 10, 2009
Messages
210
Helped
14
Reputation
28
Reaction score
14
Trophy points
1,298
Location
Lahore, Pakistan, Pakistan
Activity points
2,914
i have build this circuit
Google Images

but this does not work i adjust the values of resistance nad capacitor to give output only at 2KHz but it gives me output on all frequencies i dont know what is going wrong help me....
 

Did you see this section:
loc.cit. said:
The LM567 and LM567C are general purpose tone decoders designed to provide a saturated transistor switch to ground when an input signal is present within the pass band. The circuit consists of an I and Q detector driven by a voltage controlled oscillator which determines the center frequency of the decoder. External components are used to independently set center frequency, bandwidth and output delay.
<snip>

If the input signal has a minimum voltage of about 25 mV and the frequency around the frequency of internal oscillator, the output will be low level logic.
Click to expand...

In other words, you should get a logic low at the center frequency. What are the component values that you are using?

John
 

aliraza786 said:
i have build this circuit
Google Images

but this does not work i adjust the values of resistance nad capacitor to give output only at 2KHz but it gives me output on all frequencies i dont know what is going wrong help me....
Click to expand...

How does your circuit behave when you use a tone of 91 Hz?

John
 

it behave normaly mean if i send 91 hz or 91khz the response is same i use diffrennct capacitor and resistance to to test but it does not recognice the frequencies and when ever any signal fell at the iR reciver its out put bcome low mean it become on...............
 

Please post the exact circuit you are using and the values of all components. What are you using for a signal source (voltage, wave type)?

John
 

jhon basically i am making this circuit **broken link removed**
but this circuit responsese me on all frequency what is the problem according to you...!! soon i will upload the video of my working
 

Unfortunately, right now, your link or EDAboard seems to be hacked and goes to : **broken link removed**

I tried it several times. The first time it went to a beautiful sexy blond.

Anyway, when someone is trying to duplicate a working design and it doesn't work for them, it is often futile to try to troubleshoot the published circuit. More often, it is the questioner who has a wrong value, say a 10 uF capacitor instead of a 10nF one and so forth or a wrong connection. It has been a few years since I have used a LM567, but I have several of them in my parts boxes. If you can show exactly what you are trying to make, not "basically" or something similar, I was offering to put it on a breadboard and see how it behaves in my hands.

John
 

I understand, that you're referring to the below circuit, and 10k and 1 uF are the values of the oscillator components R1 and C1.

As jpanhalt mentioned, LM567 works fine in a lot of applications. But all circuit component need reasonable values. If you set the operation frequency to rather low 90 Hz, the PLL loop filter and detector filter have to be adjusted respectively. Review the LM567 datasheet for details.

 

ok i check the datasheet again and johan i will post the pics of my work here and i FVM posted circuit is the circuit on which i am working...
 

Fvm i studied the datasheet of 567 but i coudnt find any info about adjusting the pll loop dtector filter loop..i find only this thing helpful only.
cats.jpg
this is the datasheet u can tell me the page on which i can understand how to adjust PLL and detector filter...and can u tell me the software on which i can simulate the 567 becuse on protious i couldnt find it...
LM567 Datasheet pdf - Tone Decoder - National Semiconductor

i am making two channel remote controle but without microcontroller.
 
Last edited:

There are formulas and diagrams related to the dimensioning of loop filter C2 and output filter C3 in the national datasheet.

Unfortunately I don't know where to find a LM/NE567 simulation model.
 

What center frequency do you want to use for the first channel? Your first post mentions 2KHz, which sounds reasonable, but the discussion then digresses to 91 Hz. Let's try to get it to work at 2 KHz first. Then you can pick a second higher frequency for your other channel. What were the component values you used at 2 KHz?

John
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top