Building the Echo Base PCB

[Taylor]

Ground problem? Not having your ground wires all connected, not having ground connected to the box.

[greyscale]

Ground problem? Not having your ground wires all connected, not having ground connected to the box.

I'll double check, but I am pretty sure everything is grounded properly. Is it necessary to ground the output jack?

[Vince_b]

Yes the output jack need to be grounded. But if you use a metal enclosure and a metal jack, and you have grounded your input, your output will also be grounded without having to add an extra wire.

[greyscale]

That's what I'm doing, so it isn't that.  

Edit: When I turn my guitar volume down, the hum goes away. It diminishes when I turn the tone down as well.

[jdahlgren]

Just built this and am getting the following:

LED on and stays steady - no flashing
Only clean signal coming out, no effects
Using the clean kill switch I get no signal coming out.

All the soldering looks clean, but I'm not sure where to start troubleshooting.

[garcho]

Important 1st step:

debug

It might seem like a bogus reply, but it will make your build's trouble-shooting mysteries much easier to solve.

[Taylor]

Check with your audio probe to see if you have echoes happening at pin 14 of the pt2399. If you do, then your pedal may be stuck in bypass. That could mean something is weird with your bypass wiring (did you try to leave out the tails switch and just not do anything with those pads?) or something is wrong with the 4066 switching.  

Check to make sure you have ~5v at pin 1 of the 2399.

Once you sort out the echo situation, start to figure out why your LFO is not oscillating. Did you add the LFO kill switch? Are those pads connected?

Did you do any other mods that you didn't mention?

[pieca]

Yes, lower the value. If they list the on current for your LED you could figure it out, but I'd just make a guess. You can parallel a smaller resistor value with the current one, so just hold a smaller resistor value to the resistor pads until you find a value with the brightness you prefer. Then pull out the 50k and solder your new one in.

I haven't got any resistor in stock... I have to buy some.
I've just made a rapid test bypassing the 50k resistor, and the brightness is fine, but the led doesn't blink, probably too much current for it.

I'm considering to buy : 25k, 15k, 1M. Could it be fine or should I have to consider a lower value than 1M (i just don't want to go to my electronic shop every day  )?

Thanks for your help

[jdahlgren]

Check with your audio probe to see if you have echoes happening at pin 14 of the pt2399. If you do, then your pedal may be stuck in bypass. That could mean something is weird with your bypass wiring (did you try to leave out the tails switch and just not do anything with those pads?) or something is wrong with the 4066 switching.  

Check to make sure you have ~5v at pin 1 of the 2399.

Once you sort out the echo situation, start to figure out why your LFO is not oscillating. Did you add the LFO kill switch? Are those pads connected?

Did you do any other mods that you didn't mention?

I powered everything down and restarted.
Then started checking voltages and noticed the led was flashing...
It is working and sounds great.

[Taylor]

I haven't got any resistor in stock... I have to buy some.
I've just made a rapid test bypassing the 50k resistor, and the brightness is fine, but the led doesn't blink, probably too much current for it.

I'm considering to buy : 25k, 15k, 1M. Could it be fine or should I have to consider a lower value than 1M (i just don't want to go to my electronic shop every day  )?

Thanks for your help

1m is way too big for any regular LED. If you plan to ever build another pedal, I would recommend getting lots of different values of resistors. I don't know where you are in the world or what the prices at your local shop are like, but it's generally possible to get resistors for about one cent (.01USD). So you could get several of all the standard values for the cost of a beer (I'm not a beer drinker, but this seems to be the international unit of "cheap purchase"  ). This will come in very handy and keep you from having to go to the store every time you need a one cent part.

I powered everything down and restarted.
Then started checking voltages and noticed the led was flashing...
It is working and sounds great.

Great, glad to hear it.

[pieca]

1m is way too big for any regular LED.

sorry, it's a typo, I was thinking 1K (1000 ohm)

I'll buy some resistors and will report my result here

[Marcvv]

I build the echobase on the musicpcb pcb. It is working good except for one thing:
When tails is on everytime i switch the echobase on, there is a tick in the echo. It is not on the dry signal as you hear the tick only when the first echo starts. It does not happen when the tails is off.

Any suggestions?

Marc

[slacker]

Could be a pop from when the CD4066 switches, this would then get fed into the PT2399 so you'd hear it until the first repeats have died away. Measure the voltages on pins 1 and 2 of the CD4066 they should be about 5 volts, if one of them is off, then check/resolder the connections to the 1M5 resistors connected to the pins, probably worth checking the connections to the 47n caps connected to those pins as well.

[Marcvv]

Hi Ian,

I checked the voltages op pin 1 and 2 and they are both 3.20 volt.
I reflowed the solder joints of both 1M5 and the 47n connected. no difference.
Could it be a fried 4066?

[slacker]

Your voltages look ok, so yeah it could be a bad 4066 might be worth swapping it. Probably worth checking the wiring to the tails switch, a dodgy connection there could cause noise when switching.

[Marcvv]

Reflowed the tails switch connections. No difference.
I will have to go shop for a new 4066 to try if that solves it. Any other options left?

Thanks for reacting so fast, by the way

[Marcvv]

I replaced the 4066 and now the tick is gone. So that is solved.
Now I have another problem.
When i connect the power supply the lfo freezes. When I switch the bypass on and off, or the other way around dependinging on how i left it the last time, it starts working again. Power supply is a 1spot 9 volt.
On a battery the lfo locks up and will not work even after switching the bypass on and off.
(edit:) i read in another post that with a battery if voltage is too low the lfo will not work. So that explains that part.
Why does it lock up initially on being powered up by the power supply? Or is it always like that and I just did not notice?

[slacker]

That's a strange one, there shouldn't be any interaction between bypass and the LFO, so I can't think how switching it causes the LFO to start. Could you post the voltages on all pins of both of the opamps and the CD4066 when the LFO is locked up and working.

[Marcvv]

I did the measurements. I noticed that sometimes when the lfo locks up on connecting power it starts working after a certain time.

These are the readings:
When it is working normally:
Ic1
1=4,98
2=4,95
3=2,49
4=0
5=4,95
6=4,98
7=4,98
8=9,52

ic2
1=3,97-6,05 (varying in between these values)
2=3,42
3=4,98
4=0,59-0,77(varying in between these values)
5=3,32
6=4,90
7=2,29
8=7,05-8,49(varying in between these values)

4066
1=2,85
2=2,85
3=0
4=0
5=0
6=0,79
7=0
8=2,10-2,49(varying in between these values)
9=1,86-1,89(varying in between these values)
10=2,85
11=2,85
12=7,79
13=8,98
14=9,52

and when the lfo is locked:

Ic1
1=4,97
2=4,97
3=2,49
4=0
5=4,96
6=4,97
7=4,97
8=9,51

ic2
1=6,12
2=2,11
3=4,98
4=0,86
5=3,32
6=4,98
7=2,27
8=7,86

4066
1=2,85
2=2,85
3=0
4=0,20
5=0
6=0,84
7=0
8=2,48
9=1,80
10=2,84
11=2,84
12=7,78
13=8,97
14=9,51

any ideas?

[Barcode80]

What IC are you using? I've found that LFOs don't like certain NE5532 chips I have, and I end up with the symptoms you are referring to.