Echo Base - a new PT2399 delay

[Jim Jones]

Excellent, Michael, much appreciated!

The vero stuff is new to me and I admit it's confusing as hell at this point.  Besides, I like playing with chemicals anyhow. 

Thanks!

Jim

[DougH]

Late to the party on this one...

This is really impressive work! Nice job!

[junkwork]

perfboard layout. enjoy it. thank you
http://blogs.yahoo.co.jp/anonymousfacelesscoward/19192939.html

[John Lyons]

Thanks Junkwork! Nice one...

John

[returntable]

Hi, I'm new here, but  already built a few stompboxes and other stuff...
Now I tried the Echo Base, stripboard Layout, but there's no signal coming out(not even in Bypass) and the 7805 is getting pretty hot.
So, obviously I did something wrong, but what?
Would appreciate it a lot, if someone could help me.

(I could also post pictures, if it helps)

[Michael Allen]

you probably have a short somewhere. make sure all the components are correct values, make sure you have no solder bridges, make sure the parts are in the right place....

[soggybag]

The 7805 regulator might be wired wrong, they get hot when this happens, and I'm not saying this from experience mind you, it's just a hunch...

[mydementia]

Hi, I'm new here, but  already built a few stompboxes and other stuff...
Now I tried the Echo Base, stripboard Layout, but there's no signal coming out(not even in Bypass) and the 7805 is getting pretty hot.
So, obviously I did something wrong, but what?
Would appreciate it a lot, if someone could help me.

(I could also post pictures, if it helps)

Have a look at the image in the original post - make sure the 7805 is oriented properly.  (FYI - In the picture, the board is upside-down compared to the vero layout - get oriented, then verify component placement).
REF: http://www.diystompboxes.com/smfforum/index.php?topic=60662.0

[slacker]

To help with the debugging here's some voltages and other info that we found useful when me and Mike F were debugging his.

PT2399
1. 5v
2. 2.5v
3. 0
4. 0
5. 2.89v
6. 2.5v
7. 0.5v
8. 0.5 v
9 - 16 all 2.5v

4066
Some of the voltages change depending on if the effect is on or bypassed (off) so I've shown the voltages for the different states.

1. 4.6v
2. 4.6v
3. 0.4v
4. 0.4v
5. 0
6. 0.45v off 4.5v on
7. 0
8. 9v
9. 3v on 0.32 off
10. 4.6v
11. 4.6v
12. 8.5 on   
13. 8.5 on
14. 9

When the effect is off depending on which position the tails/Boss switch is in either pin 12 or 13 will be 1.25v the other will be about 8.7 volts.

The TL072 voltages are

U3 top left of vero

1. 5v
2. 5v
3. 5v
4. 0
5. 5v
6. 5v
7. 5v
8. 9v

U1 bottom left of vero, this is the LFO

1. changes
2. 5v
3. 5v
4. 0.8v
5. changes
6. 5v
7. changes
8. 8v

The voltages on the 5089 should change depending on the position of the bypass switch.
E. 0
B. 0.63v off 0 on
C. 0.89v off 8.5v on

These are audio probe results from the PT2399

16. very quiet signal
15. delay
14. loud delay with cyclic noise
13. nothing, or possibly a very quiet signal
12. delay with hiss
11. very quiet delay with hiss
10. very quiet delay with hiss
9 . delay with cyclic noise and hiss

[slacker]

perfboard layout. enjoy it. thank you
http://blogs.yahoo.co.jp/anonymousfacelesscoward/19192939.html

nice work anyone read Japanese?

[returntable]

Thanks very much everyone

I checked every part again, but everything seems to be in it's right place.
I found one trace I forgot to cut and one soldering bridge. The result: the 7805 doesn't get hot anymore, but still no signal coming through, no matter wether with or without effect.

The voltages I meassured mostly don't fit the ones posted by slacker.
Here's what I meassured:

PT2399
1. 5,10v
2. 1,1v
3. 0
4. 0
5. 1,64v
6. 2,43v
7. 0
8. 0,58v
9. 0,16v
12. 0,27v
14. 1,28v
The others have 2,55v

4066
1-7. 0
8. 8,11v
9. 0,71v
10. 0
11. 0
12. 0
13. 1,22v
14. 1,24v

tl072 U3
1. 2,84v
2. 1,92v
3. 5,10v
4. 0
5. 8,11v
6. 6,5v
7. 0
8. 5,1v

U1
1. 5,35v
2. 0,1v
3. 5,1v
4. 0
5. 6,62v
6. changes
7. 5,10v
8. 0

5089
e0
b0
c1,27v-on 0,75v-off

Just wondering wether a transistor could be built in the wrong way. I had a few variyng pinouts on some transitors... maybe something between the american layout and the parts here in germany?

[mydementia]

Thanks very much everyone

I checked every part again, but everything seems to be in it's right place.
I found one trace I forgot to cut and one soldering bridge. The result: the 7805 doesn't get hot anymore, but still no signal coming through, no matter wether with or without effect.

The voltages I meassured mostly don't fit the ones posted by slacker.
Here's what I meassured:
.....

Build an audio probe and follow the signal.  When Ian and I worked out my EchoBase, I had strange voltages and signal - once I probed the circuit, I found that I soldered R6 to track 8 instead of 7 - OOPS!!  Never would have found it without the audio probe.  Build one - follow signal - report back... it's worth the effort!!!
Mike

[returntable]

Yeah, I'll do that, when I find the time
Thanks a lot

Edit: fortunately plans for tonight changed, so I was able to do the audioprobe right away...
And my first question will out me as an amateur
Are the resistors R1 and R2 supposed to distribute the incoming audio signal to the other tracks? If so, they aren't... even though they are the right ones.

[returntable]

I finally found the mistake I made... There was a very small shortcut on the input track, where it should be cut.
Thanks to a magnifying glass I found it

It finally works and I like it a lot

[returntable]

I'm really sorry to bother all of you again, but unfortunately an other problem occured.
Turning the Mod Speed Knob gives to audible change. I resoldered the wires about 3 times now, but that doesn't seem to be the problem.
Could it be the Pot? I used a 1MLin pot.

[Michael Allen]

Could you be more specific? What kind of change? what does it sound like?

[returntable]

Okay, more specific: The Pot has no effect on the sound at all. I can turn it as much as I want, but nothing happens.

EDIT: So, for some reason the Mod Speed Pot works now... I didn't change anything, i just played around with the delay and suddenly it worked.

[junkwork]

calm down, look solder side CAREFULLY.

[returntable]

that's what I did about 15 times now. Didn't find anything...

Could it be possible that the Modulation sets out, when the pedal is powered with a not completely full Battery? I put in a new one and it worked for a while.
I'll test it with a DC Adaptor soon to see if this could be the case.

[slacker]

the modulation probably won't work with a weak battery, it's probably better to use a DC supply.
The current draw is about 25ma if anyone's interested.