Timeline for Why can't this circuit amplify the oscillator signal?
Current License: CC BY-SA 4.0
17 events
| when toggle format | what | by | license | comment | |
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| Oct 28, 2020 at 9:03 | comment | added | rackandboneman | Also, how are you probing the output? A 10:1 with a mile long ground wire connected to a breadboard that is already full of mile long current loops is not going to display anything meaningful.... | |
| Oct 28, 2020 at 6:00 | history | tweeted | twitter.com/StackElectronix/status/1321330882301644800 | ||
| Oct 28, 2020 at 1:32 | history | became hot network question | |||
| Oct 27, 2020 at 20:12 | comment | added | Bruce Abbott | How long are the leads to your battery? Compare that to the length of wire in your coil, and consider the inductances. | |
| Oct 27, 2020 at 20:00 | answer | added | Frog | timeline score: 4 | |
| Oct 27, 2020 at 19:43 | vote | accept | sa as | ||
| Oct 27, 2020 at 19:43 | comment | added | sa as | @bruceAbbott,I was using battery | |
| Oct 27, 2020 at 18:56 | answer | added | Kevin White | timeline score: 10 | |
| Oct 27, 2020 at 18:47 | comment | added | Bruce Abbott | Where are your power supply bypass capacitors? | |
| Oct 27, 2020 at 18:42 | history | edited | JRE | CC BY-SA 4.0 |
added 12 characters in body; edited title
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| Oct 27, 2020 at 17:58 | comment | added | sa as | I thought parasitic capacitance in the breadboards are too small to affect it,I'll try it on a pcb or like Manhattan style. | |
| Oct 27, 2020 at 17:47 | comment | added | Aaron | " i don't understand why does this oscillator output decreases when frequency increases" breadboards have a lot of parasitic capacitance. What happens to a signal passing through a capacitor as frequency goes up? | |
| Oct 27, 2020 at 17:40 | history | edited | TonyM | CC BY-SA 4.0 |
Typo' fix in title.
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| Oct 27, 2020 at 17:40 | comment | added | Aaron | Expanding on @BrianDrummond comment, use a class C amplifier topology for RF, not class A. | |
| Oct 27, 2020 at 17:38 | comment | added | user16324 | Its gain is 10 at low frequencies : designing an amplifier fo a specific gain at 40MHz is not something to tackle in a comment, but start with a capacitor across R7 and an RF choke or a 40 MHz parallel tuned circuit in place of R4. Also, dead-bug it on a piece of copper clad PCB : breadboard WILL NOT do. | |
| Oct 27, 2020 at 17:38 | comment | added | jonk | Yeah. When I'm working on a 40 MHz oscillator, the very first thing that comes to mind about building it is to use a solderless breadboard. NOT. The first thing to do is to build that in a proper way. Perhaps try the Manhattan style? | |
| Oct 27, 2020 at 17:30 | history | asked | sa as | CC BY-SA 4.0 |