Neovibe finished and now for some finetuning

[alfafalfa]

Just finished my Neovibe and I was lucky , it fired straight up.
It sounds good when I compare it  with Steve B's  demos.



There one small problem so far ;it choruses fine but  I can't get the fast speed Steve gets.

Did anyone have a similar problem or does  anyone know how to solve it ?

Some other pics : http://i113.photobucket.com/albums/n233/alfafalfa/IMG_0001-1.jpg
                        :  http://i113.photobucket.com/albums/n233/alfafalfa/IMG_0002-1.jpg



Alf

[snoof]

depending on the bulb that you used, it may not be able to keep up w/ the LFO, the rise/fall of the LFO might be faster than the speed that the bulb can go from off to on.  Can you sub in another bulb??  It could also be that the LDR's aren't capable of altering their resistance that fast either.

[SteveB]

Good deal!

Lower the value of R42 & R43. The schematic calls for 4.7k, but I had put in 2.2k's a few years ago. That sped things up a bit.

Earlier this year, I piggybacked some more resistors on top of the existing 2.2k. I measured, & it is somewhere in the 1k range +/-. Yeah, I'm lazy, but it it sounds good to me....

Steve

[alfafalfa]

I just lowered the two resistors and it has more speed now but it also lowered the lightintensity the bulb is able to deliver.

Thanks guys , for the advice . I wille have to experiment a bit more.

Alf

[John Lyons]

Lower the value of R42 & R43. The schematic calls for 4.7k, but I had put in 2.2k's a few years ago. That sped things up a bit.
I used 1K as well. You can tweak the trimmer to get the brightness back up.

Serously though... Take an hour and search for neovibe and or univibe and all the mods are in the forum here if you look for them.
I was planning on getting everything in one place but it has not happened yet....

John

[alfafalfa]

I will search for some more information John and I already have a lot on my computer must take some time to read all of it.
I have tweaked the bias trimpot but find that it has to be lowered from 200 ohms to zero for the best brightness. So thére's no adjustment left.

One more thing I read about people having trouble with the ac on the board , I don't have any hum so farso that's a good thing.

Alf