yet another mxr dist+ cry out for help :)

[jplebre]

Hey all

Have been planning a dist+ (before I tried the beginner project)
So, I tried to go the hard route and plan the veroboard layout myself.

Built it, no distortion whatsoever. Exactly the same sound with or without the 3dpt switch engaged. I have a pedal that I built with aligator clips coming of it that I used to test the beginner project and I can guarantee issue is not in the switch.

this is my layout. Can anyone help to see what the issue could be?

Boost pot does nothing, volume pot works, not distortion. Using Tonepads schem and suggested parts

http://tonepad.com/getFile.asp?id=115

[arma61]

I know it's a stupid question... anyway.... did you cut the traces under the IC 

[jplebre]

some voltages:

- battery 8v
-IC 8v on both pin 7 and 4
3.8v on pin 3

Where else would be required some voltages reading?

[jplebre]

Yeap!

Just imagine 4 crosses under the IC

[arma61]

some voltages:

- battery 8v
-IC 8v on both pin 7 and 4
3.8v on pin 3

Where else would be required some voltages reading?

I don't know about the other pins but pin 4 MUST be 0V, it's connected to grund!

[deadastronaut]

theres this layout already done..it may help. even if only as a reference..

http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album17/album06/mxr_dist_plus_001.jpg.html?g2_imageViewsIndex=1

good luck.

[jplebre]

Indeed!

I think the jug of pimms is beginning to affect me
Battery - 8v
So does pin 7 of the IC
Pin 2 and pin 6 - 3.9v
pin 3 - 3.3v
pin 4 - 0v !!!! (ufffff!

[jplebre]

Hey Astronaut

I referenced that drawing when I made this one as I had a few doubts about what I was doing.
Guess i'll look at that one more attentively (but it's missing a cut isn't it? )

[deadastronaut]

hmmm not sure, havent built it myself....

i think the port is getting to me too...

i find it easier to do a vero layout using a schematic... are you using diy layout creator prog?...

[jplebre]

eheh! enjoy our wine (I'm from Porto

I tried DYILC 3.0.8 but it looks dreadful compared to the layouts you guys post...
(I'm on mac any good suggestions? don't mind to pay a small fee if that's the issue!)

Cheers
J

[arma61]

Hey Astronaut

I referenced that drawing when I made this one as I had a few doubts about what I was doing.
Guess i'll look at that one more attentively (but it's missing a cut isn't it? )

give me 5 mins, that layout is known to have a missing cut .. need to find the link

bbs

Armando

[arma61]

ther you go m8

http://www.diystompboxes.com/smfforum/index.php?topic=74691.msg607418#msg607418

but looks like you have that cut in place!

[jplebre]

so it looks my layout could be correct then?

Also, I've found too many conflicting info on the pots. Any post with a discussion that actually ends up with a conclusion?
And, the ground being split through 2 tracks (with a jumper) - can pot's that are going to ground and components that are going to ground too be drop on whichever? Or are there considerations to be had (like audio devices and ground loops?)

[petemoore]

  Also, I've found too many conflicting info on the pots. Any post with a discussion that actually ends up with a conclusion?
  100k audio is good for volume control.
   What do you want the gain pot to do ?
  50k linear [tapered?] worth of gain reduction spreads 'distortion settings' across the sweep pretty good, eliminating the 'schrunchin' of distortion fine-tuning to the last 5% of knob rotation. Works great for 'distortion' title, but loses the ability to go very low gain.
  Anything else can work but the circuit it's connected to has a steepening as the pot is turned toward 0 ohms = max gain.   
And, the ground being split through 2 tracks (with a jumper) - can pot's that are going to ground and components that are going to ground too be drop on whichever? Or are there considerations to be had (like audio devices and ground loops?)
  All the grounds made common works. Often this looks like a ground-bus for the onboard grounds [a solid wire or wires soldered along the 'bottom' of the board] but can be any wire/layout. The offboard ground wire must make all the offboard ground markings of schematic, there are no great currents to be concerned with most 9v projects, test that all ground markings 'beep' with the DMM to ensure they've been made common.

[jplebre]

sorry kinda lost you here

What do you want the gain pot to do ?
  50k linear [tapered?] worth of gain reduction spreads 'distortion settings' across the sweep pretty good, eliminating the 'schrunchin' of distortion fine-tuning to the last 5% of knob rotation. Works great for 'distortion' title, but loses the ability to go very low gain.
  Anything else can work but the circuit it's connected to has a steepening as the pot is turned toward 0 ohms = max gain.   

Was trying to do the same as the "original" mxr dist+ would do. Now, I think i got everything up untill the bit "circuit it's connected to has a steepening ..." what exactly makes that?