New Effect: Payback

[The Tone God]

The 3PDT switch is a valid option. If you want a "blink at the end of playback" LED you could tap a LED off the PLAYL input.

Andrew

[Valoosj]

but then I would have 3 leds?
one that goes to port 16, one with the 3pdt, and another at the playl port?

[The Tone God]

Yeah. Thats why I thought reusing the vibrato gate was a valid option. I have to think about this one.

Andrew

[Valoosj]

thanks
I just want the 2 leds, the rest of this whole version 1.1 is all good

[Valoosj]

ok, almost ready to order all of this stuff. Just one question, are the pots lin or log? or reverse log?

and I have a parts list, can you check this please?

Resistors
7x 1K
2x 33K
9x 100K
2x 1M

Elco
6x 1uF
3x 10uF

Capacitor
8x 0,1uF

Pots
2x 100K
1x 10K

1N4148

1 LED (which one should I get? this is the one that you don't see on the outside)


Thanks in advance

[Valoosj]

I am checking the pcb that Michael Allen made, and I just noticed something. Pins 12 and 13 of the 4093 are grounded, while this is not in the schematic. what about pin 11? why is this left blank? Pin 3 of the ISD has the same story, but in the schematic it is clear, because there is a cross at the end of it's line connected to that pin. Have I missed something while reading through the article?

I heard that I should make the volume pot log, and the others lin, is this correct?

[Michael Allen]

When using CMOS chips, you need to ground the inputs of unused opamps for noise control, and leave the output unconnected. That is why the unused amp in the CD4093 has the inputs grounded and the output unconnected. It's not written, it's just understood when you use CMOS chips. Just another general circuit tidbit you pickup...

Hope you have luck building this one, I can't seem to find the IC yet. I'll give this layout a go when I get it.

[Valoosj]

I posted your layout on another forum, and I had some comments on it.

The IC's are available through digikey

comments: put a 7805 to create the 5v from 9v
move C17 closer to pen 14 from 4093  as it was specified by Andrew

I tried to go through the entire thing, but I'm still to green to find my way through it all

[The Tone God]

The pots for record and playback can be log. I presume the third pot is tone which could be linear. The LED can be any type. I tried out more the a dozen different types of LEDs of various colours, sizes, and brightness and all worked. I would just order another one of what you are already using.

Andrew

[Valoosj]

If I wanted to add vibrato, would I use gates 11,12 and 13 of the 4093?



I would like to add this possibility, but I don't understand where the Clock goes to on this picture. What exactly is it? It has the same sign as the in and output.
As far as the tranny and R1 are concerned, which type and value should these be?

[The Tone God]

If I wanted to add vibrato, would I use gates 11,12 and 13 of the 4093?

The block you have posted is the piece that would disables vibrato during a recording and enables the vibrato during playback. You don't want to have vibrato on during recording as your recording would have vibrato as well as the playback.

I would like to add this possibility, but I don't understand where the Clock goes to on this picture. What exactly is it? It has the same sign as the in and output.

If it has the same sign as an input or output then it must be an input or output. Quoting from the article:

Connecting a clock source to the Rosc input altering the voltage will change the clock speed and pitch of the playback. You can use a clock source of your choice and set it to you tastes.

This means that you have have to provide your own clock source. Payback v1.0 had an on board clock source but some people didn't like it and it made it hard for various mods. With Payback v1.1 I removed the clock source and gave people the option to use whatever clock they wanted as well as the interface for other mods.

As far as the tranny and R1 are concerned, which type and value should these be?

R1 will depend on the clock source you choose. The transistor can be just about any NPN you have lying around. Type will generally not matter.

Andrew

[Valoosj]

If I wanted to add vibrato, would I use gates 11,12 and 13 of the 4093?

The block you have posted is the piece that would disables vibrato during a recording and enables the vibrato during playback. You don't want to have vibrato on during recording as your recording would have vibrato as well as the playback.

I would like to add this possibility, but I don't understand where the Clock goes to on this picture. What exactly is it? It has the same sign as the in and output.

If it has the same sign as an input or output then it must be an input or output. Quoting from the article:

Connecting a clock source to the Rosc input altering the voltage will change the clock speed and pitch of the playback. You can use a clock source of your choice and set it to you tastes.

This means that you have have to provide your own clock source. Payback v1.0 had an on board clock source but some people didn't like it and it made it hard for various mods. With Payback v1.1 I removed the clock source and gave people the option to use whatever clock they wanted as well as the interface for other mods.

As far as the tranny and R1 are concerned, which type and value should these be?

R1 will depend on the clock source you choose. The transistor can be just about any NPN you have lying around. Type will generally not matter.

Andrew

The vibrato should be as you describe it. But the ports I need to use for it, are they 11, 12 and 13 of the 4093? In the bloc I posted it says 1, 2 and 3, but those are used already. OR should the entire schematic be adapted when adding vibrato?

What do you mean with that clock thing? Should I just search on clock? I have no idea on what you mean by this, exept for those things one would use to tell the time 

[The Tone God]

The vibrato should be as you describe it. But the ports I need to use for it, are they 11, 12 and 13 of the 4093? In the bloc I posted it says 1, 2 and 3, but those are used already. OR should the entire schematic be adapted when adding vibrato?

If 11, 12, 13 are what you have leftover then yes use them.

What do you mean with that clock thing? Should I just search on clock? I have no idea on what you mean by this, exept for those things one would use to tell the time 

Search around for terms like "LFO" and modulation type effects then rip the LFO section out of the circuit. I think for testing I used the LFO out of the Bullitt circuit I have at the site. Fairly simple, quiet, and provides a decent sine wave for smooth vibrato.

Andrew

[solarplexus]

Will the IC ISD1020AP from smallbear work on the Payback and the Payback 1.1 ??

[The Tone God]

Will the IC ISD1020AP from smallbear work on the Payback and the Payback 1.1 ??

No. Payback v1.0 uses the ISD25xx and Payback v1.1 uses the ISD1600B. The ISD1020 that Smallbear sells is intended for the Mobius Trip Looper found at GGG.

Andrew

[solarplexus]

Is there a place I can buy either one of them that don't have minimum $$ orders and ship to Canada?

[Auke Haarsma]

Ask Valoosj, he ordered some chips (for me too ).

[Valoosj]

Is there a place I can buy either one of them that don't have minimum $$ orders and ship to Canada?

Digikey. It cost me (and Auke) 60 euro in total for 6 chips.

[solarplexus]

Is there any substitute for the CD4093 ?

[DWBH]

Perhaps the CD4011?