EchoBase Help (Sabro Vero Layout)

[slacker]

I can't see anything obvious wrong from your photos, it all looks good all the soldering is nice and neat, connections look good.
The problem could be with pins 1 and 2 of CD4066 try, jumpering those with the CD4066 plugged in, you can connect from the vertical jumper between C10 and pin to pin 1, or if you can't get a clip on pin 1 connect it to Level pot lug 3.

[canman]

This build hates me!  I jumpered pins 1 and 2 as you suggested (had to utilize lug 3 of the level pot) and still nothing. 

I'm wondering if maybe this would be a better solution...hardwired the effect on, and use your tails daughterboard from this link: http://www.diystompboxes.com/smfforum/index.php?topic=92036.0

Would that work?  Or is this a "hope springs eternal" situation?

[slacker]

If it works fine when hardwired then yeah the tails board would work, that's admitting defeat though.

To me it still seems like a problem with the CD4066, could you measure the resistances between pins 1 and 2 and between pins 3 and 4 with the effect on and bypassed.
With it on both sets should measure something like 100 Ohms, with it bypassed one set should still measure about 100 Ohms and the other should measure at least 3Meg Ohm, probably more.

[canman]

Well, my meter has finally bit the dust.  It'll measure volts, but it won't do resistance.  I'm going to go pick up a meter later today and I'll post the resistance across those pins.

Thanks for sticking with me on this...I feel bad this thread keeps annoying the rest of the board here, if people would prefer we take this to PM's just say so!

[canman]

OK, I got a new meter (which I will be returning...I hate the user interface...gonna get a different one online I guess) and tested the pins.

The resistance across pins 1-2 in the off position would not give me a reading.  In the on position, I got around 85 ohms.

The resistance across pins 3-4 in the off position was about 85 ohms, and stayed the same in the on position.

Raise any red flags?

[slacker]

I don't know if that's good news or bad news!
That's exactly what you should see and it means the CD4066 is working.
I'm a bit stumped now, it works when you remove the 4066 and jumper the pins, so everything else seems to be ok. The CD4066 seems to be working but when you put the two together the pedal doesn't work.  Apart from bad connections between the 4066 and the socket, I'm out of ideas.
Anyone else want to tag in

[duck_arse]

.... annoying the rest of the board here, ....

that's my job. is there a link to a circuit diagram I missed?

[slacker]

The circuit is etched into my brain, I don't need no stinking schematic.
Googling "musicpcb echo base" will get you as close as you're going to get. The CD4066 uses different pins, the opamps might as well.

[canman]

I don't know if this makes a difference, but I don't use the standard opamp sockets...I just use these transistor sockets from tayda: http://www.taydaelectronics.com/30-pin-dip-sip-ic-sockets-adaptor-solder-type.html

I use them because it's easier to get links under the sockets, and it's also easier to remove the chip if need be, for me at least.  Could these be the issue?  Maybe making bad contact?  I've never had an issue using these before, but there's a first time for everything I suppose.

[duck_arse]

tayda, huh? there must be some way to blame them.

try jambing a lead cut-off between each op-amp pin and socket, see if it is connections.

[slacker]

Nothing inherently wrong with those sockets, worth trying what DA suggested though at this point I can't see what else it can be.

The schematic is here http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=42626&g2_serialNumber=1 The layout also includes some mods not shown in the schematic but nothing that has an impact on the problems canman is having.

Different sections of the CD4066 are used on the layout as follows:
Schematic       Layout
U4A                 U4B
U4D                 U4A

[canman]

You guys are rad!!  I did as you suggested DA...stuffed some lead cut-offs in with the chip, the thing fired up right away!  I'll be sure to log that one into my brain...I had no idea those sockets could lack a solid connection.  Very interesting.

So, onto some more juicy stuff.  With humbuckers, the delays distort quite a bit.  I can kind of get clean distortions when I split the coil, but it's still a bit too crunchy.  From videos I've seen, the repeats are clear as a bell.  Is this something I can fix with a resistor or capacitor swap?

I also noticed that the feedback knob and switch are both pretty sensitive...is there a way for me to adjust that as well?

EDIT:  I found this in the original EchoBase thread, on page 109 ( ) http://www.diystompboxes.com/smfforum/index.php?topic=60662.540;wap2  Seems like these mods may do it for me, though I'm still uncertain about the distortion on the repeats.  I thought the humbucker switch in the vero layout removed the diodes from the circuit?  This switch doesn't really do much for the distortion, if anything at all actually.

Thanks for all the help guys, I really appreciate it!  This is a very cool delay and if I can get it tweaked the way I need it with my rig, I'll be extremely stoked!!!

[slacker]

Great to hear you got it working, it's pretty unusual the have problems with sockets like that, maybe it's a case of slightly loose or over sized sockets and slightly too thin pins on the CD4066, pretty unlucky what ever the cause.

If it distorts with the feedback at low levels or off, then the diode switch won't do much because it's the PT2399 clipping so the sound is already distorted before it gets to the diodes. Swapping R24 and R27 for 22k resistors should clean it up, a lot of people do that mod. Do that first and then try increasing R34 to tame the feedback pot and R36 for the feedback switch.

[canman]

Dude.  THANK YOU.  Seriously, this thing sounds AWESOME.  Thanks not only for the help, but also for sharing such a great circuit with the community (yes, I'm a little late to the party, but still...thank you!!!)

I replaced R24,27 with 22k as suggested (well, first I did 20k, and I couldn't get self-oscillation...not a huge deal, but all good delays can self-oscillate!) and it solved the feedback switch problem as well.  It still takes a little finesse to dial in the feedback knob, but that's not a problem.  The delays don't distort, they're clean as a whistle.  The modulation sounds fantastic, the feedback switch is actually a useful function now...seriously, thank you.  This is the delay I've been looking for!!!

You are the man!!!  You too, DA...without your clever idea I'd still be confused as heck!!

ONE QUICK EDIT:

I have noticed an increase of noise/hum since the 4066 started working properly, both when the effect is on and in buffered bypass.  I've got a ton of alligator clips connecting everything right now, and I notice when I put my hand over some of the alligator clip wires and the humming decreases...is this just hum that comes from the circuit not being boxed, or should I be looking for something that could be causing this noise?

[bluebunny]

is this just hum that comes from the circuit not being boxed

Probably (it's where I'd put my money).  Put it in a box and tell us!       My Echo Base is like a baby sleeping.

[duck_arse]

canman, you've provided added weight to my "case against tayda", I'm afraid. the other day I was messing with some DC plugs from them, they wouldn't fit their own jax. then the plastic handles literally crumbled to dust between my fingers. switches, dc jax, dc plugs, those sockets .....

into the bin! as micallef would say.

[canman]

canman, you've provided added weight to my "case against tayda", I'm afraid. the other day I was messing with some DC plugs from them, they wouldn't fit their own jax. then the plastic handles literally crumbled to dust between my fingers. switches, dc jax, dc plugs, those sockets .....

into the bin! as micallef would say.

Glad I could help!  Haha!  This is actually only the first issue I've come across with Tayda stuff...I guess I've had good luck with them?  Every now and again they'll send the wrong number of caps, but I can live with that.  For someone like me, they're good enough, haha.

With the hum...I'm planning on boxing it up but I don't have a box for three stomps right now    I have a 1590BB but I  think cramming 3 footswitches in it might be too close together...what do you guys think?