My phase 90 clone isn't working

[andy-h-h]

Better?

It still needs to be cleaner.  Even a small spot across tracks can be a problem on vero - see marked-up image.  The tracks in between conductive strips should not have anything in them at all.   

The areas with big black marks etc are still concerning.  There's a lot to clean-up.

As others have said, scrape it clean with small screwdriver.  Sometimes a reflow with the soldering iron and flux is also needed before you can do this.  It's really difficult (near impossible) to scape off solder that's overflowed across tracks.   If you have isopropyl alcohol (99% alcohol) give it a light spray afterwards and a clean with a toothbrush just to be sure.

[snow123]

I hope this is an improvement

[snow123]

actually the signal just comes out as more distorted but quieter, not weaker.

[andy-h-h]

actually the signal just comes out as more distorted but quieter, not weaker.

Still haven't seen any voltages.  It'a guessing game without them.   

[stallik]

After using the blade/screwdriver between the tracks, I use a stiff, dry toothbrush to polish it up and remove the last bits of crud that I can't see. Any discolouration of the solder at this point should be reflowed.
I'm lucky to have an extremely powerful dissecting scope that really shows how dirty vero can become. One little bit of crud left over is all it takes to break the circuit

[snow123]

actually the signal just comes out as more distorted but quieter, not weaker.

Still haven't seen any voltages.  It'a guessing game without them.   

i have the multimeter on 200 DCV with the black probe to ground and the red probe to the legs/pins, and i used a battery snap that plugs into the dc jack for powering the circuit.
transistor voltages: (Q1-Q4 are 2n5457s instead of 2n5952)
Q1
D = 8.1
S = 8.2
G = .9

Q2
D= 8.1
S= 8.2
G= .9

Q3
D = 8.1
S = 8.2
G = .9

Q4
D= 8.1
S= 8.2
G= went from .8 to .9 and stayed at .9

Q5 (2N4126 instead of 2n4125)
C = 4.8
B = 5.2
E = 8.2



ICs (top to down)

IC1 (top)
P1 = 8.3
P2 = 8.3
P3 = switched between 8.0 and 8.1
P4 = 0.0
P5 = 8.0
P6 = 8.3
P7 = 8.3
P8 = switched between 9.0 and 9.1

IC2 (middle)
P1 = switched between 8.2 and 8.3
P2 = 8.3
P3 = 8.0
P4 = 0.0
P5 = 8.0
P6 = 8.3
P7 = switched between 8.2 and 8.3
P8 = 9.0

IC3 (bottom)
P1 = switched between 8.2 and 8.3
P2 = switched between 8.2 and 8.3
P3 = 5.6
P4 = 0.0
P5 = randomly switched between 6.5, 6.6, 6.7, and 6.8
P6 = 6.9
P7 = switched between 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8.0, 8.1, 8.2, and 8.3
P8 = 9.0

D1 (5v1 zener)
Anode = 5.4
Cathode = 8.1

[andy-h-h]

Hello

Those voltages are pretty off - compare to this  http://www.generalguitargadgets.com/pdf/ggg_p90_instruct.pdf   

Check your biasing first, and see what's happening there.   Sometimes it's good to pull the IC's etc out and see what's happening without them (voltage where it should not be)

[snow123]

how would i check my biasing tho

[snow123]

ok, when i took out the ics i got this:

Q1 - Q4 voltages:

D = 8.3
S = 8.5
G = 3.9

Q5 voltages:

C = .7
B = .9
E = 8.5

[andy-h-h]

ok, when i took out the ics i got this:

Q1 - Q4 voltages:

D = 8.3
S = 8.5
G = 3.9

Q5 voltages:

C = .7
B = .9
E = 8.5

What voltages are you getting in the empty sockets?   I'd check for continuity across the tracks - good chance you still have issues as you have voltage where it doesn't belong. 

Is D1 definitely a 5.1 zener?   

[ElectricDruid]

how would i check my biasing tho

What's the voltage across the 250K trimmer R22, or equivalently between the legs of C6/10uF?

It should be 5.1V because D2 is a 5.1V zener diode that sets the bias, but on yours it looks like it's over 8V, so something's up.

(Note I'm using part names from http://www.generalguitargadgets.com/pdf/ggg_p90_sc.pdf - I don't know if the the perf layout renamed things or not).

[snow123]

im pretty sure the vero layout im using is based on this tonepad schematic/pcb: http://www.tonepad.com/project.asp?id=7

[snow123]

ok, when i took out the ics i got this:

Q1 - Q4 voltages:

D = 8.3
S = 8.5
G = 3.9

Q5 voltages:

C = .7
B = .9
E = 8.5

What voltages are you getting in the empty sockets?   I'd check for continuity across the tracks - good chance you still have issues as you have voltage where it doesn't belong. 

Is D1 definitely a 5.1 zener?

wait i just realized i accidentaly desoldered d1's anode lmao

[snow123]

ok, when i took out the ics i got this:

Q1 - Q4 voltages:

D = 8.3
S = 8.5
G = 3.9

Q5 voltages:

C = .7
B = .9
E = 8.5

What voltages are you getting in the empty sockets?   I'd check for continuity across the tracks - good chance you still have issues as you have voltage where it doesn't belong. 

Is D1 definitely a 5.1 zener?

ok these are the IC socket voltages without the op amps in them
IC1 (top)
P1 = 0.0
P2 = 0.0
P3 = 4.2
P4 = 0.0
P5 = 4.2
P6 = 0.0
P7 = 0.0
P8 = 9.0

IC2 (middle)
P1 = 0.0
P2 = 0.0
P3 = 4.2
P4 = 0.0
P5 = 4.2
P6 = 0.0
P7 = 0.0
P8 = 9.0

IC3 (bottom)
P1 = 0.0
P2 = 0.0
P3 = 2.9
P4 = 0.0
P5 = 3.2/3.3
P6 = 0.0
P7 = 1.4
P8 = 9.0

[snow123]

how would i check my biasing tho

What's the voltage across the 250K trimmer R22, or equivalently between the legs of C6/10uF?

It should be 5.1V because D2 is a 5.1V zener diode that sets the bias, but on yours it looks like it's over 8V, so something's up.

(Note I'm using part names from http://www.generalguitargadgets.com/pdf/ggg_p90_sc.pdf - I don't know if the the perf layout renamed things or not).

with the black probe on ground, all the transistors and op amps in the sockets, and the trimpot maxed out, heres the trimpot voltages:

fixed end 1: 4.2
fixed end 2: 0.0
variable end: 4.2

[snow123]

and i am using a battery snap for voltages and stuff so voltages might be a little off

[snow123]

when i put the DMM on diode test mode and put both probes on D1 i get about 1.71 volts.

[snow123]

btw i did fix d1's solder joint lol right after i mentioned it

[andy-h-h]

Any photos of the board from above showing all components?   

[snow123]

Any photos of the board from above showing all components?