I'm using fairly match Qs and I've reflowed solder twice to fix small problem...
But the real kick in the pants seems trimmer pot that seems to be buggy... sigh will replace and see if it fixes the problems... if not then I'll post voltages and maybe you dudes can give me a hand.
Ok I need some help...
Currently the circuit is passing signal and it is around unity, but I'm not getting the phase sweeping effect.
I think the problem is in the trimmer pot area. I notice that as I am turning the pot pot I get the phase effect.... which I guess would be normal. Also When the screw driver is turning the knob and I hold the screw driver and touch the guitar string I get the effect for a bit... I think all I'm doing is shorting the pot to ground and that is changing resistance and giving the sweep effect... will post voltage in a second... just got into a LoL game.
Got pictures and sus you check the pinout of the fets? What layout are you using?
SQUASH THAT BUG!!
http://www.diystompboxes.com/smfforum/index.php?topic=29816.0
for now, replace the trimmer and see if it works. check the zener diode in the circuit...
but we need voltages, etc
Quote from: Ark Angel HFB on July 26, 2013, 06:25:34 PM
But the real kick in the pants seems trimmer pot that seems to be buggy
By "buggy" if you mean moving in and out of a distorted sound, than it's working fine.....that's normal.
Jimi's advise is correct, assuming you're using a 5.1 volt zener, try changing it to 4.7v or 5.6v.
Ok inc voltage reading...
http://www.sabrotone.com/wp-content/uploads/2010/08/MXR-Phase-90.gif Here is the vero I used...
Anyway the ICs had the same voltage reading except for IC3 Pin 3 and Pin 5 which was a little lower.
IC 1 & IC 2 = 1(5.05) 2(5.05) 3(4.95) 4(0.00) 5(4.95) 6(5.05) 7(5.05) 8(8.05)
IC 3 = 1(5.05) 2(5.05) 3(3.42) 4(0.00) 5(4.45) 6(5.05) 7(5.05) 8(8.05)
Q 1-4 All had the same readings... honestly pretty happy with the match job I did.
D: 4.95
S: 5.05
G: .066 to 2.85 depending on where the trimmer pot is set.
Q5
E: 5.05
B: 4.46
C: 3.24
Anything else?
OH OH one more thing... the Rate pot doesn't do a damn thing(didn't move it during voltage test so it might change a voltage) but the switch for script/block does change the sound a bit... just it is very subtle... and completely a mute point without the phase effect.
You should have oscillations on IC1 pins 5, 6, and 7.
Look for a bad solder joint or a solder bridge.
Even if you looked before.....look again.....closer. :icon_wink:
Also that layout has some hidden cuts you can't see. Under D2 for example
I C... see what I did there...
I'm aware of the under cuts... I copied that Vero Design over and built from this
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/Phase90_zpsdd27447a.png) (http://s73.photobucket.com/user/Ark-Angel-H-F-B/media/Phase90_zpsdd27447a.png.html)
Do you see any problems with it? All I did was add an extra line and change where the ground came in so that i could add some better power filtering.
Also... What would cause the lack of oscillation? could it be a bad chip?
A bad IC is always the scapegoat! :icon_wink:
Look for a cut that is not "cut" completely, bad solder joint, ect.
I had trouble with this layout. I scratched and rebuilt and it works great now.
My problem the first time was that it would phase but there was a volume drop with noise every couple seconds. Never knew why. I know that doesn't help you but my point is it's probably a mistake you haven't found yet. Same as what I was told.
the phase trimmer should be best somewhere around the middle. you can set it by ear... listen thru your amp CRANKED UP a bit CLEAN and listen to the phaser..
too much to the let or right it will get fuzzy and cut out. you wanna tweak this til you get the most phasing with the least noise and the least distortion.
that's right.. it's gonna be a compromise to a point.
looks to me like there's a voltage problem on that last ic... i bet there's a tiny bridge somewhere you can't see without really looking for it...hard
Quote from: pinkjimiphoton on July 27, 2013, 12:48:39 AM
the phase trimmer should be best somewhere around the middle. you can set it by ear... listen thru your amp CRANKED UP a bit CLEAN and listen to the phaser..
too much to the let or right it will get fuzzy and cut out. you wanna tweak this til you get the most phasing with the least noise and the least distortion.
that's right.. it's gonna be a compromise to a point.
looks to me like there's a voltage problem on that last ic... i bet there's a tiny bridge somewhere you can't see without really looking for it...hard
Right, but above someone said I should be getting oscillation on IC1... pin 5, 6, & 7. All voltages everywhere are stable.
Let me restate... the circuit is Passing signal... it is at or above unity... turning the trimmer(changing the resistance to ground) give the effect as you are turning the pot...
Since I am assuming the rate knob control the part of the circuit that make it oscillate and the rate knob currently does nothing... what part of the circuit is responsible for the oscillation that should be the area to look for problems?
Is the 2n4125 the Q that controls the oscillation of resistance to ground?
ARE you getting oscillation there? if so, then the phaser's sweeping, and the problem is somewhere in the audio path, probably the mixer stage.
the oscillation looks like the voltage jumping all over the place... if you're getting that, try replacing that last opamp.
IC1B (pins 5, 6, and 7) is the LFO IC.
The above pins should not be "stable." The voltage on these pins should be moving up and down.
Look for the problems I mention above and that C10 is oriented correctly.
Did you socket the ICs or solder them?
Any chance of pictures of your build?
Quote from: armdnrdy on July 27, 2013, 01:21:38 AM
IC1B (pins 5, 6, and 7) is the LFO IC.
The above pins should not be "stable." The voltage on these pins should be moving up and down.
Look for the problems I mention above and that C10 is oriented correctly.
Did you socket the ICs or solder them?
Any chance of pictures of your build?
I'll post pic but they won't be pretty... in trying to solve this I've solder and re-solder a few times and so thing are a bit less net than I'd like... gezz I feel like I'm a teen again and my buddies just walked into my dirty bedroom. lol give me five minutes
Battery for my cam is still charging... might be time to get a new one.
Anyway I re-check again heated my iron ran it between the track to make sure there were no solder jumps...
I re-checked the voltage reading again and there is no oscillation of an kind anywhere.
got frustration so I'm jumping in a LoL game and then I'll try changing the ICs and taking pics for you guys.
I forgot to mention a problem with my second try with this and it sounds like the same problem If I understand what you said.
I did forget the cut under D2 and the phase would only work as I turned the trimmer. Try around there again. to make sure the cut is clean.
plz don't judge me... it was clean and neat once... T_T
To make larger... right click and hit open in new tab... that will give them to you really big.
I didn't have a 15uF cap so I paralleled a 10uF and a 4.7uF...
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/DSCF2554_zps3d7b50ed.jpg) (http://s73.photobucket.com/user/Ark-Angel-H-F-B/media/DSCF2554_zps3d7b50ed.jpg.html)
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/DSCF2556_zps34fe2eb5.jpg) (http://s73.photobucket.com/user/Ark-Angel-H-F-B/media/DSCF2556_zps34fe2eb5.jpg.html)
Why did you convert the layout? I mean that's ok to do but it'll make it very hard for someone to look for a problem visually. Meaning one would have to trace the verified layout to verify yours first, then check out your build.
What's going on with IC2? How you used a IC socket then used the DIP sockets with the transistors.
Sorry I can't help really, a bit too hard to tell what's going on. I want to help as I don't get to often but having built the layout twice with one fail and a success I thought I'd chime in somehow.
Tip on the jumpers, don't worry about stripping insulated wire for the smaller jumps. Just use some component clippings. Easy bend and solder.
Also just taking some time looking at your layout it. Seems very wrong.
Just one point first, I'm confused about your 9v connection. Does it have two connections? The main where you have a black solder pad connecting to pin 1 of IC1, hitting the two upper left 10k resistors and jumpered to one of the 50nf caps.
Also do you have the output jumpered to two rows?
OR, I think you're drawing in how you loop the wires through the board? Maybe this.
Yeah I think I see that with the layout. I won't delete though, just a part of my observation.
Quote from: Focalized on July 27, 2013, 06:11:57 AM
Why did you convert the layout? I mean that's ok to do but it'll make it very hard for someone to look for a problem visually. Meaning one would have to trace the verified layout to verify yours first, then check out your build.
What's going on with IC2? How you used a IC socket then used the DIP sockets with the transistors.
Sorry I can't help really, a bit too hard to tell what's going on. I want to help as I don't get to often but having built the layout twice with one fail and a success I thought I'd chime in somehow.
Tip on the jumpers, don't worry about stripping insulated wire for the smaller jumps. Just use some component clippings. Easy bend and solder.
I always make a new vero of vero I find and add proper power filtering..., just a 100ohm and a 220uF cap. That is the only change.
the double socket is because I'm a moron and solder the first socket in on row to high... so instead of trying to fight to get 8 solder joints hot... I just made the two socket for the q's 4 long and used the extra hole for the IC.
I've stupidly always solder sockets on last... so by the time I realized the mistake I didn't really want to worry about it to much... on the upside those two open socket in that row shouldn't hurt anything and I don't think that is the problem.
Quote from: Focalized on July 27, 2013, 06:26:44 AM
Also just taking some time looking at your layout it. Seems very wrong.
Just one point first, I'm confused about your 9v connection. Does it have two connections? The main where you have a black solder pad connecting to pin 1 of IC1, hitting the two upper left 10k resistors and jumpered to one of the 50nf caps.
Also do you have the output jumpered to two rows?
OR, I think you're drawing in how you loop the wires through the board? Maybe this.
Yeah I think I see that with the layout. I won't delete though, just a part of my observation.
I use the pad to signal a hole be drilled in the board to loop the wire so no strain is placed on the solder joint once the wire is feed through the whole.
Ever built a board and after moving stuff around trying to fit it in a box, a wire break or a joint break... I did... ONCE...
I said never again and started making sure that I always had room on a board to drill extra holes and feed the cables through.
Yeah I see that, I've use the pre-drilled corner holes in Vero board to route wires.
Hope you get this up sometime. I used the layout and after my second try it really sounds nice with matched transistors. I used the trimmer outboard as it gave a good 20-30% range that darkened and lightened the tone of the phase sweep. Might not be equal in every build. Phase is my favorite effect next to a wah. I was about to buy a kit before I got it working.
Quote from: Ark Angel HFB on July 27, 2013, 05:52:10 AM
plz don't judge me... it was clean and neat once... T_T
To make larger... right click and hit open in new tab... that will give them to you really big.
I didn't have a 15uF cap so I paralleled a 10uF and a 4.7uF...
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/DSCF2554_zps3d7b50ed.jpg) (http://s73.photobucket.com/user/Ark-Angel-H-F-B/media/DSCF2554_zps3d7b50ed.jpg.html)
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/DSCF2556_zps34fe2eb5.jpg) (http://s73.photobucket.com/user/Ark-Angel-H-F-B/media/DSCF2556_zps34fe2eb5.jpg.html)
bro, you realize the chip on the right isn't plugged into the socket right right? look at that picture. if it's been like that unnoticed (i've done similar) that could be an issue!! ;)
@pinkjimiphoton : I noticed that in the layout the top right IC is one row lower than the top left IC. There are sockets below the IC socket on the top right that the chip is plugged into as well, so it should be fine (if not a little strange).
The OP explains in reply #21 that he made a mistake which resulted in the "Macgyver" socket hack.
I still think that he's looking for a bad cut or solder bridge which is pinning the LFO at Vref instead of allowing it to oscillate.
Quote from: armdnrdy on July 27, 2013, 03:06:05 PM
The OP explains in reply #21 that he made a mistake which resulted in the "Macgyver" socket hack.
I still think that he's looking for a bad cut or solder bridge which is pinning the LFO at Vref instead of allowing it to oscillate.
Which IC should be oscillating... using my vero.
According to the Sabrotone link that you supplied, this vero is based off of the Tonepad schematic.
The Tonepad schematic shows the LFO as IC1b pins 5, 6, & 7.
EDIT:
Taking a closer look at the Sabrotone layout and the Tonepad schematic, it appears as if Mr. Sabro changed the component designation for the LFO and didn't supply a schematic.
The LFO on the Sabro Vero is IC 2
I'm trying to get reading in every resistor to check and see if something is off... having a hard time getting steady readying with my multi-meter.
the circuit isn't pluged in... and all Qs and ICs have been pulled... but when I try to test most of the resistances around IC2 and IC3... the value starts at one number and the climes.
Is this some weirdness with to do with the zenar Diode or is the curse spreading?
You can't get an accurate reading of a lot of resistors "in circuit" unless you unsolder and lift one leg. (don't lift your leg....the resistor's leg!)
I'm still betting on an uncut trace or a solder bridge. The voltages of the ICs look OK accept for the LFO.
Quote from: Ark Angel HFB on July 27, 2013, 07:37:07 PM
I'm trying to get reading in every resistor to check and see if something is off... having a hard time getting steady readying with my multi-meter.
the circuit isn't pluged in... and all Qs and ICs have been pulled... but when I try to test most of the resistances around IC2 and IC3... the value starts at one number and the climes.
Is this some weirdness with to do with the zenar Diode or is the curse spreading?
There are these things called capacitors that are still in the circuit that along with other resistors will give you false readings.
Get a sharp knife and run it between the tracks, and you should be able to feel even the smallest solder bridges.
Quote from: psychedelicfish on July 28, 2013, 01:12:07 AM
Get a sharp knife and run it between the tracks, and you should be able to feel even the smallest solder bridges.
I took the solder iron put a pencil thin tip on it and ran it between the tracks I honestly don't think it is a solder birdge... I've just gone over the track so many times...
I know there is a problem but if it isn't the placement... and it isn't the chips or Qs... then idk what it is...
the only other problem I can think of is that in resolder over and over a jumper or part lead slide out and is no longer really connected but with the Zener Diode in teh circuit I can't get steady reading from my muilt meter to find if a joint is bad...
What I might just build a new one. If that vero is verified then everything should be ok...
Is there a chance the power filtering I added is somehow the problem?
Also is it not weird that the rate knob does nothing... I mean I guess it would be a sign something is wrong with the LFO. Everything seems to be working fine other than the LFO. The circuit passes signal... the sound is not dull or muted... the trimmer pot effects the sound... but there is no oscillation / phase effect.
I hate to resurrect an old thread, but I'm having the exact same problem. Did you ever figure out what it was?
Quote from: adm66gal on February 13, 2019, 02:08:41 PM
I hate to resurrect an old thread, but I'm having the exact same problem. Did you ever figure out what it was?
Scratch that, I had a 15n cap to ground on the LFO instead of a 15u (pounds head on computer). Works as advertised!
Quote from: adm66gal on February 17, 2019, 03:05:21 PM
I had a 15n cap to ground on the LFO instead of a 15u (pounds head on computer).
Initiation complete. Welcome to the nut-house. :D