Hi,
I have built what seemed to be a simple 555 timer circuit with variable resistors to adjust the output frequency of the 555 timer.
There seems to be some issues with the circuit when viewed on my PC based O/Scope & i would like to ask for some advise regarding these issues as i am inexperienced in electronics.
I have attached the Schematic of the circuit.
All tests done with 12V input:
First up, i noticed there is a "dip or voltage drop" --(not knowing the correct electronics term) in the signal along the peak voltage lines so the peak signal is not clean.
Attached as "Voltage Drop"
The second issue is the voltage output is not stable & seems erratic, i am not sure if it is characteristic of this particular circuit or i have some problems?
The output voltage will stay stable for a few seconds & then becomes erratic & starts jumping around in small increments & keeps increasing until it jumps from around 5v to just over 20v for a few seconds & then goes stable again & so on.
I noticed that the output frequency also changes when it jumps to the lower voltage marks as can be seen in the attachment.
In the Attachment --Erratic Voltage--i have captured the changes in the output voltage--Again with a constant 12v input.
I have another attachment--Frequency-- that shows the Minimum to Maximum Frequency of the Circuit. The higher frequency is not clean, i would like to get a nice clean signal.
Seems i have a few issues & i am not sure if it is the particular circuit design or not?
Any help would be greatly appreciated.