Hello, can somebody help wich transistor is like bfg520

[michael1978]

It will not work. I told you and showed you:
1) L1 must be parallel with its tuning varactor but instead it is wrongly in series with it.
2) The value of C1 is 1 million times too much at 220uF and instead should be 220pF.

i make also parallel, but no success

 

[davenn]

i make also parallel, but no success

and did you change the value of C1 ?

 

[Audioguru]

Please post the schematic with parts values and a photo of the last circuit that did not work.

 

[WHONOES]

Hi again. See attached my version of your oscillator which does work. Simulated using Simetrix.
To actually make this sort of simulation work, you often need a perturbation of some sort to initiate oscillation. That is what the extra bits "V2 and C5" are for. They combine to give a very short pulse at the junction of C3 and L1. To set the pulse from V2, right click it and then set up as in the third attachment "Set V2".png.
To get best sine wave resolution, click on "Simulator" on the menu bar, make sure "Transient" is selected, click on "Advanced Options" at the bottom of the window the in the next window, set "Max Time Step" to 50p then close that window.
Now simulate and you should get the same results as me.

 

[michael1978]

and did you change the value of C1 ?

No sir

 

[Audioguru]

C1 is an electrolytic capacitor that has too much inductance for it to work at the high radio frequency.

 

[michael1978]

C1 is an electrolytic capacitor that has too much inductance for it to work at the high radio frequency.

what to do? can you tell wich value to set to capacitors and i wanna try please, do you rembmember you said in parallell

 

[michael1978]

Hi again. See attached my version of your oscillator which does work. Simulated using Simetrix.
To actually make this sort of simulation work, you often need a perturbation of some sort to initiate oscillation. That is what the extra bits "V2 and C5" are for. They combine to give a very short pulse at the junction of C3 and L1. To set the pulse from V2, right click it and then set up as in the third attachment "Set V2".png.
To get best sine wave resolution, click on "Simulator" on the menu bar, make sure "Transient" is selected, click on "Advanced Options" at the bottom of the window the in the next window, set "Max Time Step" to 50p then close that window.
Now simulate and you should get the same results as me.

Thank you a loottts for time and help thanks

 

[michael1978]

C1 is an electrolytic capacitor that has too much inductance for it to work at the high radio frequency.

i gonna send you tomorow the schematic i go to seep

 

[davenn]

No sir

what to do? can you tell which value to set to capacitors

C1 .... the 220uF should be a 220pF, preferably a disc creramic

 

[michael1978]

C1 .... the 220uF should be a 220pF, preferably a disc creramic

I did it 47p and 100p connected to resistor 1

 

[michael1978]

I did it 47p and 100p connected to resistor 1

is working so

I did it 47p and 100p connected to resistor 1

I did it 47p and 100p connected to resistor 1

I change 220p 220p
do you know why i cant get clear waveform sine?

 

[michael1978]

Hi again. See attached my version of your oscillator which does work. Simulated using Simetrix.
To actually make this sort of simulation work, you often need a perturbation of some sort to initiate oscillation. That is what the extra bits "V2 and C5" are for. They combine to give a very short pulse at the junction of C3 and L1. To set the pulse from V2, right click it and then set up as in the third attachment "Set V2".png.
To get best sine wave resolution, click on "Simulator" on the menu bar, make sure "Transient" is selected, click on "Advanced Options" at the bottom of the window the in the next window, set "Max Time Step" to 50p then close that window.
Now simulate and you should get the same results as me.

Hello sir, i make min, but i dont know why i dontt get wavefrome like yourss? and idea, is nice software i like it

 

[WHONOES]

is working so


I change 220p 220p
do you know why i cant get clear waveform sine?
View attachment 42318

Did you set all the component values as in my schematic? including the transistors?
Also, the circuit needs R4 which is effectively the DC resistance of L1. Without it the simulator will regard L1 as a perfect inductor and it will have a very high Q.
Attach a copy of your simulation circuit to your next post. Save it as a PDF and attach as such.

 

[michael1978]

Did you set all the component values as in my schematic? including the transistors?
Also, the circuit needs R4 which is effectively the DC resistance of L1. Without it the simulator will regard L1 as a perfect inductor and it will have a very high Q.
Attach a copy of your simulation circuit to your next post. Save it as a PDF and attach as such.

I can give you my file if you want, but the valuse are the same like in begin, but i make it yours is working perfect
if i make bf199 than i get this one , maybe i confige bad the simulator, can you do something? thanks

 

[WHONOES]

I can give you my file if you want, but the valuse are the same like in begin, but i make it yours is working perfect
if i make bf199 than i get this one , maybe i confige bad the simulator, can you do something? thanksView attachment 42320

First off, I can't see your circuit behind the graph which you have superimposed over the schematic. Second, R4 is not the correct value, it should be 390R. Third, the filter will be loading the O/P stage causing the distortion that you see.
Please save schematic and graph separately as PDF's, you can do that from the file menu, and sent both of them.

 

[Audioguru]

How should he fix his broken spelling and broken grammar??
Maybe his translation software is broken?

 

[michael1978]

First off, I can't see your circuit behind the graph which you have superimposed over the schematic. Second, R4 is not the correct value, it should be 390R. Third, the filter will be loading the O/P stage causing the distortion that you see.
Please save schematic and graph separately as PDF's, you can do that from the file menu, and sent both of them.

can i send you the file better, my version is 7.2 OF SIMETRIX

 

[michael1978]

First off, I can't see your circuit behind the graph which you have superimposed over the schematic. Second, R4 is not the correct value, it should be 390R. Third, the filter will be loading the O/P stage causing the distortion that you see.
Please save schematic and graph separately as PDF's, you can do that from the file menu, and sent both of them.

Here is complete schematic 1.RAR you need winrar to uuzip

 

[michael1978]

First off, I can't see your circuit behind the graph which you have superimposed over the schematic. Second, R4 is not the correct value, it should be 390R. Third, the filter will be loading the O/P stage causing the distortion that you see.
Please save schematic and graph separately as PDF's, you can do that from the file menu, and sent both of them.

Hey man is working i change R4 is perfect sinewave. Thanks a lotttttttttt for taken so much time from you peace