>
> Yes, that´s the right ways to solve the problem!
>
> ----- Original Message -----
> From: jammie
> To: vintagesynthrepair@yahoogroups.com
> Sent: Sunday, November 11, 2012 7:44 AM
> Subject: Re: [vintagesynthrepair] ARP Omni MK1 - no sound, must be something stupid
>
>
>
>
> but you are right he should check that cap as he might of done a cold solder joint
>
> he will know once he has done the check on pin 12 of the cd4007 chip
> ----- Original Message -----
> From: Paulo Palmieri
> To: vintagesynthrepair@yahoogroups.com
> Sent: Sunday, November 11, 2012 9:38 AM
> Subject: Re: [vintagesynthrepair] ARP Omni MK1 - no sound, must be something stupid
>
>
>
>
> Sorry, I didn´t read the messages below...
>
> ----- Original Message -----
> From: jammie
> To: vintagesynthrepair@yahoogroups.com
> Sent: Sunday, November 11, 2012 7:13 AM
> Subject: Re: [vintagesynthrepair] ARP Omni MK1 - no sound, must be something stupid
>
>
>
>
> he said he replaced all the tantalum caps
> ----- Original Message -----
> From: Paulo Palmieri
> To: vintagesynthrepair@yahoogroups.com
> Sent: Sunday, November 11, 2012 9:07 AM
> Subject: Re: [vintagesynthrepair] ARP Omni MK1 - no sound, must be something stupid
>
>
>
>
> There is a tantalum cap there in the oscillator around the MK5024 that kills the oscillator. It´s common issue finding this cap shorted.
>
>
> ----- Original Message -----
> From: jammie
> To: vintagesynthrepair@yahoogroups.com
> Sent: Sunday, November 11, 2012 6:26 AM
> Subject: Re: [vintagesynthrepair] ARP Omni MK1 - no sound, must be something stupid
>
>
>
>
> first thing set you oscilloscope to the master oscilator
>
> and make sure your getting a square wave
>
> put it on pin 12 of the cd4007
>
> this then goes to the top octave devider chip
>
> mk5024
>
> if you have no square wave generated here you will not get any output at all
>
> if you have a square wave
>
> then test the top octave devider chip pins 4/5/6/7/8/9/10/11/12/13/14/15/16
>
> these are the square wave signals for the each key note
>
> if you dont have square waves at these pins then the top octave chip is crapped
>
> these are the first 2 places to look as seeing you have changed so many items on this synth
>
>
> ----- Original Message -----
> From: Mark
> To: vintagesynthrepair@yahoogroups.com
> Sent: Sunday, November 11, 2012 5:00 AM
> Subject: [vintagesynthrepair] ARP Omni MK1 - no sound, must be something stupid
>
>
>
> I am in desperate need of some direction! I picked up a broken ARP Omni MK1 last year on craigslist as a project, because of the success I had read about online of people bringing them back from the grave.
>
> There is no sound at all coming from this synth! I am a DIY hobbyist, but not much of a schematic jockey, so I have tried to restore and overhaul the Omni. The lights light up and the switches turn the lights on and off. The power supply is spitting out -15 and +15 like it should, just no output from the main out, synthesizer out, or any other out.
>
> You guys are going to laugh.
>
> I replaced the following:
> -All tantalum caps, decoupling and envelope
> -All CD4XXX ICs, on every board (yes, I have WAY too much time)
> -LM1458s on string control board
> -LM301 on filter board
>
> Now I am at an impasse. I really want this thing working with a passion, and getting rid of it this far in the game would be a big mistake. Is there any part of the synth I should be looking at? I have an oscilloscope, should I be probing a certain place? I've worked on smaller, less complicated synths in the past, but the Omni is damn near confusing.
>
> One last question: The phaser board connector was upside down when I received it. Is there anything that could fail on the phaser board that would cause it not to make any sound?
>
> I truly appreciate your help, thank you so much for your time!!!
>