neovibe

[newperson]

Hi,

What is a replacement for Mouser part number 338-54C679?
It is the photocell (LDR) for the Neovibe.  Mouser says that they do not have it anymore.

-Paul.

[newperson]

Is smallbear the place to get it? 

[newperson]

Are there any suggestions for a person building this pedal?  I have been reading the old posts and see that several people have had a hard time with this one.  Are there any problems to look out for?  Thanks,

[alderbody]

i just built it and i still have a problem to get it to oscillate at slow speed.

i hope i'll fix it some day.

btw, i got my LDRs from small bear.

[R.G.]

I have been reading the old posts and see that several people have had a hard time with this one.

What you don't see is the hundreds who have built it and not posted. That's the oldest internet clone pedal around, and it's been successfully done many, many times.

Are there any problems to look out for?

A. Download datasheets for the transistors that you actually use and get the pinouts correct.
B. Use good soldering technique.
C. Use an isolated jack for the power connector into the box. Do not let the connector electrically connect to the box.
D. Get the capacitor polarities correct.
E. Do the wiring carefully off the board.

Those five things account for probably 95% of the problems.

[Jaicen_solo]

FWIW, the LDR's i believe this design calls for should have a resistance swing of 70-120K. It took me a fair bit of searching to find that little nugget
Neovibe's top of my list of builds after I get paid this month, I'll keep you posted

[roknjohn]

Correct me if I'm wrong, but wasn't there also a clone version that allowed you to use 4 Vactrols in place of the lamp/ldr combo. Has anyone successfully built this version? I  have built the lamp/ldr version, but had the same problem with the slower speeds. It's still in a box somewhere, never got back to it.

[R.G.]

That would be the Easyvibe. I laid out the board for John Hollis' design of that one. It's an opamp version. Good sound though by all reports.

[no one ever]

would this happen to be a great and maybe better diy version of fulltone's version of the uni-vibe? 


really, i'm curious if this is like fulltone's / uni-vox's.

[newperson]

Going to try this one out.  Parts ordered tonight.  Will be my largest project since the PT-80 delay.  Hope it works out.  I will not be changing anything from the GGG PDF layout.  Hope that is the layout to use. 

[newperson]

Hi again,
So I got most of the parts in.  I have to order again from Small Bear.  I messed up and only order 3 of the light sensors.  So anyway.  I etched an board from the GGG PDF file and it lookes way to small.  I laid some of the parts on it and it would be very tight to make it work.  I put a 35mm black film can on it and it is too small for it to fit.  How big should the board be?  Inches?  I am going to etch another one and make it bigger.  If I make it around 5inches would that be a problem?  Would making it too big be a problem?  I know too small sure is.

-Paul.

[R.G.]

would this happen to be a great and maybe better diy version of fulltone's version of the uni-vibe?

No. Fulltone's vibe is close to the circuit of the original univibe, I've heard. I have never seen inside one, deliberately.

I etched an board from the GGG PDF file and it lookes way to small.  ...  How big should the board be?  Inches?

I think you may have printed the GIF file instead of the PDF. The PDF should print at correct size. If you're trying to save NPN paper, print the PDF, measure from mounting hole to mounting hole, then print the GIF at varying sizes until you get the right one.

It's quite a tight board, though.

[newperson]

Hi,

I printed the PDF, cut it out, then scanned it along with some other ones to make a Blue sheet.  It seems too tight to fit it.  From the one I printed, the layout image looks to be the correct size because my 35mm film holder has the same size circle as the layout's drawing.  I guess I will try to etch another one when I can get another copy done.  If I happen to make it a bit bigger would it make anything weird?  I am guessing not because there are no chips in it.

Thanks for the reply,
Paul.

[newperson]

I do see there is one IC (1A 100v Rectifier) on the board.  That part fits the layout picture on my GGG PDF printout.  So I guess I should etch my next board this size.
_paul.

[R.G.]

I do see there is one IC (1A 100v Rectifier) on the board.  That part fits the layout picture on my GGG PDF printout.  So I guess I should etch my next board this size.

The diode bridge IC can be replaced by four separate diodes if you like. That would let you enlarge it a bit if you like.

[newperson]

Ok,
I made a bigger board this time.  Got all the parts on it tonight except a resistor and 2 caps that I am missing.  I have some simple questions before I finish with the board. 

First:  I think that it is really cool that all the caps polarity are in the same direction.  I did not noticed this until I started putting them all on the board. 

-What are the empty pads for?  Such as pad "P" in the middle of the board?
-Does it matter if I use sockets for the LDR's?  Would there be any benefit from this?
-Can I test the LDR's in someway before I put them onto the board?
-Does it matter if I use 14-16V AC or 20-24 VDC?  Will it change any parts?
-What position should the trimmer be in to turn it on?  Should the grounded side read the 200ohm or should the other side read it?  Or should it be in the middle.  I remember reading somewhere in the past posts about it blowing the lamp if it was in the wrong place.

I have used all the parts that are listed on the GGG PDF file.  I have not changed anything.  I have ordered the LDR's from Smallbear. 

-Paul.

[Kelby]

Paul,

Note that the wiring diagram shows one of the pots wired up wrong (I have forgotten which one), and you need to wire the pots as shown in the schematic.

I'm sorry that I can't remember the answers to your questions; I do recall having the same questions when I built mine.

[newperson]

Hi,
Thanks for telling me that.  Seems I read that somewhere also.  I will dig around and try to find which one it was.

Did you make yours with a 35mm holder or tin metal?  How tall did you leave it?  Do you think it matters the hight of it?  Seems like it would cut down on the light inside of the box with it being too tall.

I have all my parts and pots wired up already.  I am waiting till a store opens to get a 68ohm resistor and a 10uf cap to finish it.  I will have to find out which pot to change tomorrow.  I forgot to fit the lid for the 35mm film holder in there before I started.  So now I have to figure out a way to drill it without messing up my board.

Thanks again for the pot information,
Paul.

[newperson]

I have read to switch pads c and e for the speed pot to fix the layout.

[no one ever]

I have read to switch pads c and e for the speed pot to fix the layout.

thanks man, i'm about to start this project myself pretty soon.

R.G., mouser doesn't have any ac-dc adapters that put out 18v (gotta get the exact RM value for that vintage touch)... only 18vac. is this dangerous to the touch?

i searched geo for a diy solution to create 18vdc, but to no avail. if anyone could help me (us, i guess, i suppose newperson might need help too on this one) and spec a transformer for a diy solution, it would be greatly appreciated. i suppose if the power supply thing doesn't work out, i'll strap together two 9vs. at least i know how to wire that one up.