Beginner Looper Pedal

[dan5150]

I am a beginner pedal builder that has completed a few mods and a few DIY pedals. (One from a kit, and another by starting just from a PCB)

I am now interested in building a Looper pedal.

I did a forum search here and found hits on the Payback and the Trip Looper.

I also did a google search on "DIY Looper Pedal" and actualy came accross something maybe close. It is based on the radio shack circuit.

http://www.instructables.com/id/Looper/?ALLSTEPS

I am going to pick up the parts in the next few days and try it out. It says it can record up to 20 sec. I am a bit sceptical, but it seems cheap enough that it is worth a shot. 

My questions are:

Are there plans for a PCB, Parts List and layout for the latest version of the payback? (I am still a beginner) 
I see there is a PCB for the Trip Looper on GGG and Small Bear has an IC in stock that might work: ISD1020AP. Should I start with that one instead?
Has anyone played with the Radio Shack circuit and was sucsessful in using it?

Thanks for any help/advice you can provide.

-Dan-

[Dean Hazelwanter]

Hi,

I see there is a PCB for the Trip Looper on GGG and Small Bear has an IC in stock that might work: ISD1020AP.

The chip Steve stocks at Small Bear does work, I've tested it in the MobiusTrip. Also, Andrew just came out with a new release of the Payback. So, name your poison!

[stumper1]

I just finished a MobiusTrip.  Pretty easy build - nice layout at GGG.  Used the 1020 chip from SmallBear.  Works great - but, I do have a small sratch/pop type sound at the beginning of each loop - kind of sounds like an old record when it reaches the end.  Didn't hear it when I first fired it up - took it apart to paint the box, put it back together - then I heard it.  Not sure if it was always there or not.  With the levels set right you don't notice it unless playing very clean/soft.  Is this normal?

[The Tone God]

I have heard from a few people who have tried to make the Radio Hack sampler work but everyone that I have heard from have had different issues with it. I have not heard any success stories.

I believe there are couple of people working on different Payback v1.1 layouts. I haven't received any confirmations that Payback v1.1 works for others yet but it just came out.

Works great - but, I do have a small sratch/pop type sound at the beginning of each loop - kind of sounds like an old record when it reaches the end.

I don't know what maybe going on for sure but I do have any issue with the IC in my Payback v1.0 that a pop occurs somewhere after the first second or so of playback. I think I may have either damaged a cell in the memory or I wore it out. Try to record with no/grounded signal and see if it is still there.

Andrew

[Valoosj]

a looper pedal would be so nice! this is something I really need. the 5,2 seconds on my DD-6 is not enough for a lot of riffs. I took a look at the other threads as well, but is there a good schematic around, because the ones I saw just are not that clear.

I'd really like to build this one, it could help on finding other riffs in songs and stuff

[dan5150]

Thanks for the info guys!

Dean - Do you have a wiring layout diagram posted somewhere? When I built my Dist + clone based on the PCB from GGG, the wiring diagram came in really handy for the finishing touches. Also, I noticed that you are using some little connectors for all of your off board connections. Do you source those from Small Bear as well?

-Dan-

[dan5150]

Oh yea. I also read the 2 sheets on the Payback circuits on the Tone God site. Very helpfull!

I picked up a couple of the Rat Shack things last night and in looking closer at them, one of the big challenges is the input and output are shared. (This little speaker is used both as a mic and the speaker) The IC is tiny and under an epoxy blob so I can't tell what it is to try and track down the datasheet for it.

[Dean Hazelwanter]

Hi,

Take a look at http://www.diystompboxes.com/smfforum/index.php?topic=28495.0, http://www.diystompboxes.com/smfforum/index.php?topic=32651.0.

I get the connectors from one of 2 local stores that both carry the Mode line of components. To see what these connectors look like, go to here http://www.mode-elec.com/, and plug in 37-603-0 and 37-6203-0 into their part number / product search box in the upper left corner.

[stumper1]

Try to record with no/grounded signal and see if it is still there.

Tried disconnecting the input ground and shrting the input to ground - still have the noise.   The volume of the "noise" does not increase or decrease with the rec/input level.  Any other suggestions?

Thanks

[Dean Hazelwanter]

Hi,

Tried disconnecting the input ground and shrting the input to ground - still have the noise. icon_confused  The volume of the "noise" does not increase or decrease with the rec/input level.  Any other suggestions

Did you install the 0.1uF disc cap from pin 28 to pins 12 & 13 on the back of the board?

Didn't hear it when I first fired it up - took it apart to paint the box, put it back together - then I heard it.  Not sure if it was always there or not.

With the levels set right you don't notice it unless playing very clean/soft.

Is it worth the time to take it out of the box and try it, or is it something you can live with?

[stumper1]

Did you install the 0.1uF disc cap from pin 28 to pins 12 & 13 on the back of the board?

Like this?

Is it worth the time to take it out of the box and try it, or is it something you can live with?

Tried that...same thing.   I can live with it but if I can fix it that would be cool.  THANKS for the tips.

[The Tone God]

The only thing I can think of is to try the output with just a speaker. If the pop is still there then it is an issue with the IC. Otherwise I lack experience with this circuit to help anymore.

Andrew