electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Articles  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links  |  Store
Forum with support of Syndicator RSS
 FAQFAQ   CalendarCalendar   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   LinksLinks
 RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in  Chat RoomChat Room 
Live streaming at radio.electro-music.com

  host / artist show at your time
  Jez Adventures in Sound
Please visit the chat
 Forum index » DIY Hardware and Software
Delay guitar pedal into synth module
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [3 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
Silesius



Joined: Feb 12, 2010
Posts: 61
Location: Berlin

PostPosted: Mon Jan 21, 2013 12:51 am    Post subject: Delay guitar pedal into synth module
Subject description: Syncing to a clock?
Reply with quote  Mark this post and the followings unread

Hi, I'm trying to modify a Digitech Digidelay pedal to use in my eurorack modular [I can't afford an Echophon right now]. So far, I've managed to adjust the levels, using the CGS stompbox adapter, and add some voltage control over the time parameter using a vactrol.
The pedal uses the usual pushbutton [spst off-on] to engage it, but this button has other functions as well. It works as a tap tempo button [to sync the repetitions] and it is used to put the looper in record mode [it has a looper too!].
So I thought it wold be great to put a jack in my front panel where you can engage the button by sending clocks and gates to it. That would make the pedal a very useful delay in a modular context. You could remote control the looper and sound on sound functions, and sync the delays to a clock [not an Echophon, but good enough Wink ].
As said, the switch is very simple, it just has two poles; I measured the voltage and I found 3.3v on one pole and about 0v on the other. So I thought that if I send a 3.3v gate to the 0v pole I would be faking a button push. But that's not working. All the components are smd, and I'm not very good with technical questions, so I'm not sure about how to do next. It seem like an easy mod, but now I'm stucked.
Any ideas about this? Maybe I could use something like a cmos 4066 to engage the button??
Back to top
View user's profile Send private message
Boogdish



Joined: Sep 21, 2009
Posts: 122
Location: Bloomington, IN

PostPosted: Mon Jan 21, 2013 9:35 am    Post subject: Reply with quote  Mark this post and the followings unread

You should try sending zero volts to the +3.3 side. It might be that a pin has a pull-up resistor, and the switch is grounding out this pin.

If you're unsure about this, and want to check before potentially damaging your equipment, find a known ground point on the pcb (like where the power supply comes in) and measure the resistance between that point and the cold side of your switch. If the resistance is zero (or a negligibly small number) then, the switch is meant to be a path to ground.

If you can find the voltage regulator that's providing 3.3 volts, you can then check the opposite. If there is significant resistance between the 3.3 volt supply and the hot side of the switch, then it's going through a pull up resistor, and it's safe to ground out at this point.

So, if you're wanting to ground it out using positive trigger/gate pulses, you will need an inverter. A 4066 should work, I would put a diode between the 4066 and the board, that way you don't have to worry about having too high of a voltage on the 4066 output damaging the delay, and you can still use the normal button when you're not controlling it with the synth.
Back to top
View user's profile Send private message Visit poster's website
Silesius



Joined: Feb 12, 2010
Posts: 61
Location: Berlin

PostPosted: Tue Jan 22, 2013 12:37 pm    Post subject: Reply with quote  Mark this post and the followings unread

Thanks a lot Boogdish. It's working now with the 4066. I have 4 seconds delay perfectly in sync with the clock. Now it's time to put this baby behind a nice fron panel Wink
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [3 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
 Forum index » DIY Hardware and Software
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
AmbiphonicDSP

Please support our site. If you click through and buy from
our affiliate partners, we earn a small commission.


Forum with support of Syndicator RSS
Powered by phpBB © 2001, 2005 phpBB Group
Copyright © 2003 through 2009 by electro-music.com - Conditions Of Use