Hi
Please help me to answer this quetions about electronic canary circuit


http://www.sentex.ca/~mec1995/circ/canary.gif

1- How the capacitor 103 control the frequency of the tank cicuit ? it must be for feedback only ...so if i put any value instead why the frequency changes?

2- In general in Hartley oscillator circuit they say that the gain must not exceed mor than one ..What element control the gain in canary circuit?

3- If i want to make the transformer what rules i must depend on ?..is this transformer audio or power transformer ?..is it is her for matching also?

4- If i want to increase the sound i must added another transistor amplifier ? or what?

5- How the designer choose the capacitor 100 micro ? why another value not work ?

 

Hello,

This post is moved on request of the OP from the 3D MAX thread.

Bertus

 

Mr :bertus
Please send my subject to general electronic chat

 

Hello,

The thread is moved.

Bertus

 

Hello,

The thread is moved.

Bertus

Thank you my dear Bertus

 

For full story, go to find box, upper right, this page & put in canary, scrool down to - IS there any 12V doorbell----. There is also a link to sample of sound.

 

For full story, go to find box, upper right, this page & put in canary, scrool down to - IS there any 12V doorbell----. There is also a link to sample of sound.

Thank u
I inter many links like your link and i did not found answers about my questions except that the transformer is audio transformer that has impedence of 1k Ω and 8 Ω ..how the designer limit this value to this type of audio trnsformer ..if it is 500 Ωto 8 Ω ..is the circuit will work or no?
and another question about this audio transformer ..i found it in many electronic circuit work as amatching ..How can i choose it to matching between to circuits or between any amplifier and speaker?..
Is the turns ratio is important ?
This is with respect to transformer and i wait for the answer of other questions ..Please

Thank u

 

Can any friend give me a link and i will search ..because i think that my questions is not normal and need some research

 

Hello,

Here is the intended link:
http://www.radiolocman.com/shem/schematics.html?di=62835

Bertus

 

Hello,

Here is the intended link:
http://www.radiolocman.com/shem/schematics.html?di=62835

Bertus

This is asimple explaine and i did not found in it what i look for
Thank u
I did not expect that there is no answere about my questions

 

Hello,

I will try to answer your questions:

1- How the capacitor 103 control the frequency of the tank cicuit ? it must be for feedback only ...so if i put any value instead why the frequency changes?
Other values will work, as long as it is not to small for feedback.

2- In general in Hartley oscillator circuit they say that the gain must not exceed mor than one ..What element control the gain in canary circuit?
The gain is depended on the ration of the coils.
Have a look here for more info:
http://www.electronics-tutorials.ws/oscillator/hartley.html

3- If i want to make the transformer what rules i must depend on ?..is this transformer audio or power transformer ?..is it is her for matching also?
The used transformer is an audio transformator, The core of a power transformer would most likely give problems.

4- If i want to increase the sound i must added another transistor amplifier ? or what?
You could tap the signal from the collector of the transistor with a capacitor to feed it into a power amplifier.

5- How the designer choose the capacitor 100 micro ? why another value not work ?
The 100 μF capacitor determines the speed of the tjirp.
A smaller capacitor will make it tjirp fatster.
A larger capacitor will make it tjirp slower.

Bertus

 

Thank u Mr Bertus