[sdiy] Ensoniq SQ2 repairs

[Rutger Vlek]

Hi,

thanks for the info. I have tried a couple of things with the SQ2, but still 
no luck. A believe that some of the good advices I got didn't take into 
account that the front panel isn't working either! The display works fine 
though.

So I have no control at all of this synthesizer!

- I had a response on the midi-input, but I don't anymore!
- I can still generate aftertouch and pitch/mod wheel CC's on the midi out

I have the idea that the RAM or ROM is a bit f*cked up and that stuff like 
the midisettings are totaly wrong.

I have measured every testpoint on the main pcb and the powersupply seems to 
be fine. All voltages are what they are supposed to be on the test points. 
All ribbon cables seem to be ok (I tested for conection between the socket 
on 1 end to the socket on the other end of the cable). The only thing I can 
think of is something in a processor or perhaps a software setting. I wish I 
could do a reset through the hardware...

Greetings,

Rutger

>From: "Rykhaard D.A.M.I.A.N." <rykhaard at gmail.com>
>To: "Rutger Vlek" <rutgervlek at hotmail.com>
>Subject: Re: [sdiy] Ensoniq SQ2 repairs
>Date: Sun, 24 Sep 2006 10:31:57 -0400
>
>(Please note here - I'm going from EPS experiences in the past, as I
>repaired a few of them. :) )
>
>I'd verify the connection of the ribbon cable from the keyboard's
>circuitboard, to the main board in the SQ2.  If it had been
>disconnected for servicing - check to make sure that it's not
>connected - offset to the left or right, by one pin, or, up or down,
>by 1 row of pins.
>If it's a 2 ended cable, I'd check both ends.
>If there's more than 1 cable from the keyboard's circuitboard to the
>main board, I'd check each of them.
>If they're all ok, you could try reheating each of the solderpoints at
>the circuit board areas for that cable - fluxing the points first to
>freshen the solder - for a possibly cold solder joint or blow hole.
>>From your description - it sounds to me - like the cable from the
>keyboard - isn't connecting properly, as everything else is working
>fine through MIDI, as well as the spin wheels on the synth itself.
>
>
>On 9/23/06, Rutger Vlek <rutgervlek at hotmail.com> wrote:
>>Hi everyone,
>>
>>I have searched the huge archive but I found very little information on 
>>the
>>Ensoniq SQ2.
>>
>>I'm currently working on an SQ2 (identical to the SQ1 except for the 76 
>>keys
>>instead of 61) that had an empty battery. I recplaced the battery and
>>mounted a battery holder. The result is good, the SQ2 boots normally 
>>again,
>>but has a bigger problem:
>>
>>- The instrument doesn't respond to the keyboard or the knobs on the
>>frontpanel
>>- It responds and sounds perfectly when I play it with another keyboard
>>connected to the MIDI-In, even patch changes work good and the display 
>>shows
>>the correct information. Even the SQ2's pitch and mod wheels work on the
>>sound I play from an external keyboard.
>>- No errors in the display
>>- I checked the powersupply and the power leads to the knob PCB and the
>>keyboard PCB. Both are doing fine....
>>
>>What could be wrong here? I was hoping that a system reset would work, but
>>since not any of the knobs responds I cannot initiate a reset.
>>
>>Any thoughts or maybe a service manual?
>>
>>Greetings,
>>
>>Rutger
>>
>>
>>
>
>
>--
>Take care,
>Warmth and Peace,
>Ryk
>
>http://www.sdiy.org/damian/index.html - my modular synth's homepage :)