Thats great Timescope ! Im still tinkering with it.. i have no idea how to calculate anything so im just pluging away with diffrent values having fun Mr.

 

Have fun but do not burn up all your 555 ics because you will need three for the circuit that I am working on.

You will also need two pnp small signal transistors, four npn small signal transistors and one LM358.

Transistors like BC182, 2SC945, 2N3904 etc for the npn
BC212, 2SA733, 2N3906 etc for the pnp.

Timescope

 

Cool i have all that on hand.

 

Have fun but do not burn up all your 555 ics because you will need three for the circuit that I am working on.

You will also need two pnp small signal transistors, four npn small signal transistors and one LM358.

Transistors like BC182, 2SC945, 2N3904 etc for the npn
BC212, 2SA733, 2N3906 etc for the pnp.

Timescope

Can you post any part of it.. maybe the 555 section and let me get started on that part of it?

 

Ya havent given up on it have ya Timescope?

 

I have almost finished. I hope to upload later tonight.

Timescope

 

Thank You Timescope.The schematic you posted earlier has been fun learning about the op amp.I still have ALOT to learn, even with the 555.I believe your TSG circuit will be one of the best if not the best learning block not only with the OP-AMP and 555's but equally as well with the small signal transistors! I cant say Thank You enough.. this circuit I believe will be a wanderfull tool to help ALOT of people learn All About Circuits !

 

OK, I suppose you don't want to say what you are trying to accomplish.

 

Im simply wanting to expieriment with this waveform...it produces a distinct sound compared to a triangle or sawtooth wave... it producez more surface area on aluminum capacitor plates...what really has memost interested inthe waveform is it showed up on asimple 555 circuit i was building just seeing wat all i could do but my 555 burnt up and i could not reproduce it.now after having played with Timescopes fixed frequency circuit i feel his adjustable version will help me and other novices like me have fun learning more about the 555 ,op amps and small signal transistorz.

 

Hi waveguy, I have been overloaded with work recently. First, here is the circuit that I promised to upload over a week ago. The design details are in the attached word document. If you have problems opening it, let me know and I will use another method.
I will try to finish the other variable circuit over the weekend.

C4 is 10nF

Timescope.

 

The attachment says the LM358 is not suitable, so what op-amp is appropriate? Thanks.

 

One with a high slew rate of 20v/us or more, and a differential input voltage range that includes the positive supply. I will do some research. Suggestions are welcome.

Timescope

 

Thank you Timescope !

I'll try and search as well

 

How about this one?
http://www.ti.com/general/docs/lit/getliterature.tsp?literatureNumber=sbos103

 

Thanks tubeguy, the OPA2353 will work well. It is similar to the LT1632 that I just found.

Timescope

 

One with a high slew rate of 20v/us or more, and a differential input voltage range that includes the positive supply. I will do some research. Suggestions are welcome.

Timescope

Thank you again Timescope ! I like the LT stuff so ill be finding a way to order a few of those

 

i have the lt1632 on order...hopefully be here by the weekend

 

Timescope's TSG circuit is working great ! The negative (2) slope is variable with the fixed slope circuit posted.I have just assymbled the circuit and will begin to study what all is going on within the 555 and op-amp.
Ive had to move R1 and its diode to an independant trace to get the desired output waveform.Ive also had to use a 2.2nf capacitor not having the posted 1.8nf .

 

Good job both of you!!!!

 

Great job waveguy. The variable circuit will be finished soon. Please note that it is completely different from the first circuit and is more advanced.

Hint : It uses current sources and current mirrors.

Timescope