neovibe

[Jaicen_solo]

I can't remember if it was a Dejavibe or a Captain coconut PCB I saw once, but they were using MPSA14 darlingtons in place of the 2N3904 pairs in the original. Intersting eh?

[newperson]

Got the final two parts today. 
Does it matter which way I wire the power jack?  I am going to use the 18volt DC because I already have a power supply.  Should the neg side go to the (-) side of the board? 

Thanks,
Paul.

[no one ever]

Got the final two parts today. 
Does it matter which way I wire the power jack?  I am going to use the 18volt DC because I already have a power supply.  Should the neg side go to the (-) side of the board? 

Thanks,
Paul.

yep, pad j

[newperson]

Should the sleeve be the (neg) and the tip be (pos) for the jack? 
-Paul.

[no one ever]

Should the sleeve be the (neg) and the tip be (pos) for the jack? 
-Paul.

there should be a diagram on your adapter...


what enclosure are you using?

[newperson]

Now for the debugging.

Bad hum due to it not being grounded right I think.  The Output jack only shows one wire going to it.  It should have a ground to the board right?  

No guitar sound coming through the board when on.  The light thumps and causes the thumping to come through.  The speed control changes the speed of the light and thumping.  The depth changes the brightness and the loudness of the thumping.  But no guitar sound coming through.  

Could I ground the Output jack to the ground on the input?

The sheet with the voltages on it read:

Sheet_____________My readings
Input: 17Volts______17.7
Q12:   10V_________blinking 7-11V
R40:    11.7________10.7
Q10:     5.4________5.9
R32:     6.1________.65
Q5:      4.1________4.25
R18:   10.9________12
R13:    4.1________4.9

So I have R32 really off.  Q12 Changing between 7-11.  The others are close.

Any suggestions?
All the parts are coming form the GGG PDF file.  Nothing changed.  The LDR's are from Small Bear.  The light is the RadioShack 12v 25ma one.  I have changed the speed pot wiring as stated above.  I tested all the Resistors before putting any in to get as close to the value as possible.  The switch is a blue 3pole from the forum.  All the transistors are the 2N3094 ones.


Any thoughts,
Paul.

[newperson]

the adaptor is a multi type.  I can change it from - or + ground and change the volts around.  ect.  I put it on the neg ground(sleeve) and wired the jack to be neg ground(sleeve). 

[newperson]

It is not in a box yet. 

[newperson]

Edit:  I made a mistake on the voltage reading for R32/C15

Now for the debugging.

Bad hum due to it not being grounded right I think.  The Output jack only shows one wire going to it.  It should have a ground to the board right?  

No guitar sound coming through the board when on.  The light thumps and causes the thumping to come through.  The speed control changes the speed of the light and thumping.  The depth changes the brightness and the loudness of the thumping.  But no guitar sound coming through.  

Could I ground the Output jack to the ground on the input?

The sheet with the voltages on it read:

Sheet_____________My readings
Input: 17Volts______17.7
Q12:   10V_________blinking 7-11V
R40:    11.7________10.7
Q10:     5.4________5.9
R32:     6.1________5.85
Q5:      4.1________4.25
R18:   10.9________12
R13:    4.1________4.9

 Q12 Changing between 7-11.  The others are close.

Any suggestions?
All the parts are coming form the GGG PDF file.  Nothing changed.  The LDR's are from Small Bear.  The light is the RadioShack 12v 25ma one.  I have changed the speed pot wiring as stated above.  I tested all the Resistors before putting any in to get as close to the value as possible.  The switch is a blue 3pole from the forum.  All the transistors are the 2N3094 ones.


Any thoughts,
Paul.

[no one ever]

did you fine-tune the bias of the lamp driver / adjust the clean/wet mix ?

[newperson]

I made it glow the dull orange like it said with the depth all the way down.  The clean wet mix have the two resistors on them like the layout.  I matched all the resistors with my meter before I put any of them in to make sure to have the right values.  I have read some of the other posts where they got some values mixed up.  I did not want that to happen.

I have put the sleeve ground of the output to pad "O" below "j" and "K."  This got rid of the hum.  The bypass works now.  Nice clean guitar sound when turned off.  All the functions of the pots work and change the effect like they are suppose to.  I can see them effecting the light bulb. 

Now, I have tried to put a strong signal (Boosted guitar) into the effect and found that it would pass with a farty distorted sound.  The speed, depth, and vol all work with this farty distorted sound when I pick very hard.  The distorted signal dies out very quickly also.   

I have been looking at the schematic and see that the layout has a couple different changes.  First being the Input ground going to pad "C."  The layout has it going to pad "B."

Second, The switch goes to pad "A" where the layout shows it going to pad "AA?"

Any thoughts?,
Paul.

[no one ever]

I made it glow the dull orange like it said with the depth all the way down.  The clean wet mix have the two resistors on them like the layout.  I matched all the resistors with my meter before I put any of them in to make sure to have the right values.  I have read some of the other posts where they got some values mixed up.  I did not want that to happen.

I have put the sleeve ground of the output to pad "O" below "j" and "K."  This got rid of the hum.  The bypass works now.  Nice clean guitar sound when turned off.  All the functions of the pots work and change the effect like they are suppose to.  I can see them effecting the light bulb. 

Now, I have tried to put a strong signal (Boosted guitar) into the effect and found that it would pass with a farty distorted sound.  The speed, depth, and vol all work with this farty distorted sound when I pick very hard.  The distorted signal dies out very quickly also.   

I have been looking at the schematic and see that the layout has a couple different changes.  First being the Input ground going to pad "C."  The layout has it going to pad "B."

Second, The switch goes to pad "A" where the layout shows it going to pad "AA?"

Any thoughts?,
Paul.

i believe it should go to that top A pad.

did you get a dual revlog pot?

[newperson]

I got the dual pot on the PDF file from mouser.  Dual A 100k.  I do not think that it is the reverse pot. 

Do you know if C4 and C12 have a (+) (-) side?  They are the caps that are in a clear plastic type holder.  Mouser part#23PS133  330pF and #23PS147 470pf. 

Q11 and Q12 jump around for the "E"  values.  Should this happen?  And if not how would that be fixed?  I have been looking for bad connects and see none around them.  My meter shows them connected ok. 

Should the input jack only have the tip and ring connected? 

[no one ever]

I got the dual pot on the PDF file from mouser.  Dual A 100k.  I do not think that it is the reverse pot. 

Do you know if C4 and C12 have a (+) (-) side?  They are the caps that are in a clear plastic type holder.  Mouser part#23PS133  330pF and #23PS147 470pf. 

Q11 and Q12 jump around for the "E"  values.  Should this happen?  And if not how would that be fixed?  I have been looking for bad connects and see none around them.  My meter shows them connected ok. 

Should the input jack only have the tip and ring connected? 

i believe so, as there's no battery and thus no need for power conservation.

doesn't that mouser pot work reversely? as in 5 o clock is slowest

[newperson]

I tried a larger power supply because someone in a past post solved a buzzing problem with this pedal with more power.  It did not fix my problem.  The past post said that a wall wart will read more voltage when not plugged into an effect.  So I tried one that reads over 24volts.  The sticker says 24volts, but it reads more.  This did not solve the problem though. 

How many ma does this thing need?  Could that be my problem?  My power supply that reads 19volts has 1000ma or 1amp.  The one that reads over 24volts offers 600ma.  On the only post where the person solved the buzzing problem, they had a 2amp 24volt supply.

-Paul.

[newperson]

I have been messing aaround with the unit today and tried 16VAC with it.  Same thumping problem/no guitar sound.  I audio probed around and found that there is nothing coming out of Q1.  The guitar sound stops here.  The base has the guitar but nothing else attached to the transistor.  Should there be sound coming out the E or C of this transistor?  Is this the amp stage?  I am going to look at all the resistors and caps and Q2,3 around this area.  If I short out this area of the back of the board with my hand the effect with the guitar comes through shortly.  I have blown up 2 Q12s so far by messing around shorting at the back of the board. 

Paul.

[R.G.]

I audio probed around and found that there is nothing coming out of Q1.  The guitar sound stops here.  The base has the guitar but nothing else attached to the transistor.  Should there be sound coming out the E or C of this transistor?  Is this the amp stage?  I am going to look at all the resistors and caps and Q2,3 around this area.  If I short out this area of the back of the board with my hand the effect with the guitar comes through shortly.

You have found your problem area - at least for this problem.

Measure and post the DC voltages of each pin of each transistor Q1-Q4.

[newperson]

Hi,

Just the person I was wanting to write me.  I have replaced Q1, Q2, C1, C3, and R5 to see if there would be any changes.

I have found that if I touch the base pin (with my finger or the tips of my meter probe) of Q1 to R5 it clicks and then the effect works as it should for about a min or so.  It then fades aways to static till no more effected input signal passes.  At this point it goes back to the thumping of the light.  If I touch the pins together again it starts this working process all over again. 

Q1: E1.09, B of Q1 moves down to 0 from .03 then stays at 0, C3.25,
Q2: E2.6, B3.25, C2.7
Q3: E2.1, B2.73, C14.1
Q4: E4.9, B4.84, C15.6

Thanks for any help.  I have been messing with this all day.
Paul.

[R.G.]

I have been messing with this all day.

Yeah. I've been messing with it since 1993.  

Q1: E1.09, B of Q1 moves down to 0 from .03 then stays at 0, C3.25,

Q1 base being at 0 would account for your problems if that's a real reading. Check the values of R1 -R11 by measuring the resistance with an ohmmeter. Then check the resistance from Q1 base to Q2 emitter (should be 1.2M) and the resistance from Q1 base to ground. Also measure the voltage at the junction of R4 and R5.

There are two possibilities. (1) you could have a problem with the base of Q1 being shorted or open (2) there could be too little current coming through R4/R5 to let the thing get biased up. The checks above should let you catch those.

[newperson]

Ok here is what I got:

R1: 19.05K          Paper says: 22K
R2: 21.8K            Paper says: 22K
R3: 33.6K*  reads 46.2 out of circuit. Replaced with 46.1.  Now reads 33.5K in board     Paper says: 47K
R4: 1.2M             Paper says: 1.2M
R5: 98.8K            Paper says: 100K
R6: 6.78K            Paper says: 6.8K
R7: 1.103M* reads 1.202M out.  Now reads 1.19M back in.        Paper says:  1.2M
R8: 1.195K          Paper says: 1.2 K
R9: 3.28K            Paper says: 3.3K
R10: 46.8K          Paper says: 47K
R11: 4.7K            Paper says: 4.7K

Q1base to Q2 E: runs right over 2M
Q1 base to ground runs up over 2M, but seems to be right over 2M

Took Q1 out.  Reads 129.  Replaced with another Q1 with 128 reading.
New Replaced Q1 base to Q2 E: reads 1.98M
New Replaced Q1 to ground reads 1.97M

Do not see where the R4/R5 junction is but:
Top of R5 is 13.44V
Bottom of R5 is 15.61V

Top of R4 starts around .3 then runs down to 0V
Bottom of R4 runs down to 0 also.

Tested the effect again and got the same no input signal passing until it touch Q1 base to R5.  Then the effected input signal fades out like before.

Does this help any?
Paul.