Idea for a half sweep phaser

[iainpunk]

Eyyyy

That schematic you posted up there, the R1 determines fall time and R2 determines rise time, just put in 1meg pots( possibly in series with 1k ohm to set minimum  time) in stead of both resistors so you can control both the rise and fall time.

The nonlinearity of the led might come from the fact it needs a certain voltage to turn on.

Hope this helped somewhat.

[patrick398]

Thanks for the suggestion Iain. I think i took that circuit about as far as i could in terms of getting what i wanted out of it. I've abandoned it now in favour of a tremulus lune lfo with which i can get pretty close to what i'm after. I want really know until i hook it up to the phaser though so watch this space
Thanks again everybody for your help and suggestions

[duck_arse]

patrick398 - seeing as this is your thread, if you wanted to post a photo, say, of your cro in use, showing people the front-panel settings and switch positions, well, who could say - no, you can't? who? and people might look and say, switch A to position C, like that, and another Robert would have a [niece/]nephew.

[patrick398]

I don't have a camera phone unfortunately so posting photos is always a bit of an issue haha. I usually have to borrow my flat mates phone when he's in. Point taken though, in the future i'll try and take photos as i go so you guys can guide me in the right direction easier. My TL082's have just arrived so i'm going to put together that circuit that Mark posted, see where that gets me.

However, IF the LED coming off the trem lune circuit i've got on the breadboard at the moment is anything to go by i've got high hopes for it working nicely with the phase 90..but i'm more than ready for a fall from grace 

[Kipper4]

Did you notice the Lune lfo is made with a single op amp (the second op amp is used as a buffer for the led)

link to scheme
http://fuzzcentral.ssguitar.com/tremulus/tremulusschematic.gif


Where as the linked one from Mark is a dual op amp circuit.
Q1 is the led buffer.

[patrick398]

I did not notice that but can see it now you've pointed it out, thanks!