The Vibe, didn't phase

[spoontex]

I've just build the " The Vibe ", but I haven't no effect... I've think that I checked all the components and shmeatic whitout luck. Anybody can help me?

Thanks.

http://www.guitarpcb.com/PDF%20Files/The%20

http://4.1m.yt/sVhRcZc.jpg

IC1:
1: 149.5mV
2: 4.59V
3: 4.34V
4: 0
5: 149.7mV
6: 4,58V
7: 9.93V
8: 10mV

IC2:
1: 4.57V
2: 4.57V
3: 4.57V
4: 9.94V
5: 0
6: 0
7: 4.58V
8: 4.57V
9: 4.57V
10: 4.57V
11: 0
12: 4.57V
13: 4.57V
14: 4.57V

IC3:
1: 0
2: 158.7mV
3: 5.98V
4: 0
5: 0
6: 9.30V
7: 9.91V
8: 0

Q1:
G: 0
S: 4.57V
D: 4.56V

Q2:
G: 0
S: 4.58V
D: 4.57V

Q3:
G: 0
S: 4.58V
D: 4.57V

Q4:
G: 0
S: 4.57V
D: 4.56V

Q5:
E: 4.59V
B: 3.98V
C: 2.44V

D1:
+: 0
-: 4.58V

[Kipper4]

http://www.guitarpcb.com/PDF%20Files/The%20

Page not found

[spoontex]

http://www.guitarpcb.com/apps/webstore/products/show/7240161

Try this.

[Kipper4]

IC2 volts look good


Edited I should RTFM


Do you get an lfo wobble at the gate of the fets?

[Kipper4]

Out of intrest did you do some of the mods?

[spoontex]

RTFM?

Isn't it extrange that the gate of each fet get 0 volts? I didn't get any kind of wobble...

First when I finished I made a mod, but later when I see that can get any phase I uninstalled the mod.

[Kipper4]

RTFM;Read The F*&%£ing Manual.

Your lfo is slammed at the plus (+9v) rail. It should wobble some where between 4v5 and 9v on the Dmm. (If I RTFM right)
Check the values around the lfo (IC3) and twiddle the TR1 too.
What volts are you getting at R30?

[spoontex]

The R30 have, 2,160v and 1,98v to the other leg. I've change the trim and nothing... it's rare...

[Kipper4]

Disconnect power and see if you made a poor resistor choice in the lfo.
Also check the orientation of any polarised caps.

[Mark Hammer]

I'm not sure why the 33k feedback resistor (R16) is suggested.  Feedback on a phaser sounds nice.  Feedback on a vibe does nothing useful. The reason is that where the notches on a phaser (and adjacent peaks) are focussed, specific, and identifiable, vibes produce broad shallow dips, rather than notches.  So there is really nothing to emphasize via feedback.

If the builder wishes to use same-value caps across all 4 phase-shift sections to make a phase-shifter (the board supports both phaser and vibe), then consider replacing the 33k resistor with a 12k fixed resistor in series with a 22nf cap and 25-50k pot.  But if the goal is vibe, then leave R16 and the toggle off.

[spoontex]

I've checked all the components, they seems be ok... and don't understand...

[Kipper4]

Have you checked around the lfo with a magnifier for bad joints, cold solder joints?
You can use the DMM in continuity mode to check for bad joints too.

[Mark Hammer]

One of my preferred practices for troubleshooting is to clean the flux off the copper side of the board.  The flux does not do anything "bad", but can often make it difficult to spot solder unintended bridges or cracks.  Those aren't always the reason for things not working, but it's nice to be able to cross things off the list and know that "it's not that".

As it happens, I was having issues with a Rocktave octave divider I was boxing up the other day, and the flux actually WAS making it hard to see an unintended bridge between two pads.

[spoontex]

Nothing... nothing... it is desespearte.... Recheck all again and nothing...

[spoontex]

I've voltage betwen 9v+ and terminal In and Out !!! This is normal?!?!?!

[spoontex]

Habemus Vibe.... Now I get some wobble. I upload a demo. This is how it should sound? It's more like a vibrato than a phase no?!?!

https://soundcloud.com/david-rotger-florit/vibe

[pinkjimiphoton]

in that circuit, unless the gain of the q's is at least around 260, it won't phase at all.
make sure you have the proper pinouts and are using the specced jfets.

i hate to say it, but you may be better off buying a matched set from guitar pcb or from steve at small bear,
IF you can find the specc'd jfet... i forget... 2n547 or something like that... you gotta buy around 100 of them or more to find FOUR that will be close to what you need. major hassle and not worth it imho. i bought a couple bags of them and didn't get a single matched quad of sufficient gain to work in this circuit. best i got was around half the reccomended gain or vgs or whatever ya call it. as barry says, if it's belo 260 or so, throw 'em out. (well, don't throw 'em out, they'll be useful in other things, just not this circuit)

if you are doing the vibe mods to the p90 circuit, you can't pick and choose... the "vibe" is bypassing the 3rd and 4th stage of the phase 90 circuit (feedback will only work in p90, not p45 mode... p45 is the "vibe" mode in this project). since the feedback comes from the last stage it cannot work in "vibe" mode at all.

like rich said, RTFM

the vibe, in vibe mode, is nothing but a vibrato.  it's a phase 45 with the dry signal gone. in the other mode, it's a phase 90, and is intended to be used with either switchable feedback or a feedback pot. i found in my build the pot was too much hassle, and stuck a fixed 33k resistor in there. the more standard 47k you usually see caused feedback oscillations on the tops of the sweep.

this particular circuit is killer in a crybaby shell... you may need to adjust the "low" range of the speed pot with a trimmer between wiper and pin 1 of the 500kc pot.

if ya need a good pot for that, the best you can get imho is from forumite joe gagan, his smooth pots are the only thing i will use in treadle based effect pedals. and his 500k reverse audio is perfect for this circuit.

[pinkjimiphoton]

I'm not sure why the 33k feedback resistor (R16) is suggested.  Feedback on a phaser sounds nice.  Feedback on a vibe does nothing useful. The reason is that where the notches on a phaser (and adjacent peaks) are focussed, specific, and identifiable, vibes produce broad shallow dips, rather than notches.  So there is really nothing to emphasize via feedback.

If the builder wishes to use same-value caps across all 4 phase-shift sections to make a phase-shifter (the board supports both phaser and vibe), then consider replacing the 33k resistor with a 12k fixed resistor in series with a 22nf cap and 25-50k pot.  But if the goal is vibe, then leave R16 and the toggle off.

this is normally built with switches to bypass the last two stages of the phaser, mark. it can be a p45 with no feedback, or a p90 with feedback used at will on a switch or pot. that's why the 33k resistor is suggested... it's for the normal "stock" circuit, not the vibe mod.

also, in this circuit "univibe cap values" (.015,  .22,  .47, .0047uF) for the 4 swept stages sound absolutely KILLER. a 4 stage phaser is a 4 stage phaser, it's not gonna sound identical to the univibe without the lamp, but it's mos def close enough for rocknroll. even with just the first two stages used, it gets a nice rather asymetric wobble to it.

[spoontex]

First, thanks for all.

I bought 4 matched transistors from banzaieffects. The univibe cap's are interesting. I can put in the place of each 10nf that I want? Or specific place?

Thanks.

[pinkjimiphoton]

yessir, those are the stock univibe values in the correct order, you can change those caps to whatever sounds best to you. in some cases if you go too big, it may stall the lfo tho. socket and experiment. barry uses completely different values in his, and his sounds amazing too.
once ya get it right i think you'll love it bro