I will probably forward the OBXa to my technician, as he's pretty good with all the computer stuff.
I'm more into the analog :-)
But thanks for your help and best,
Thomas
On Dec 5, 2012, at 1:56 PM, Roger J wrote:
Been a couple of years since I did an OBXa. One of the ways to work on issues related to a CPU that will not run is to ground the data bus of the CPU. This will cause the address bus to auto increment, and with an o-scope, one can do a lot. As I recall , there is a slide switch that will do this. There is also a switch to engage the calibration routine.
Do you have the calibration document? As I recall it talks about the no-op too.
Do you have the calibration document? As I recall it talks about the no-op too.
From: Thomas Heckmann <troperecordings@t-online.de>
To: vintagesynthrepair@yahoogroups.com
Sent: Wednesday, December 5, 2012 4:32 AM
Subject: Re: [vintagesynthrepair] OBXa diagnostic EPROM needed
HI,it's powering up, but just a few LEDs are on and no sound or response from the keys to the voiceboards.The Z80 is fine, too.Thanks,ThomasOn Dec 5, 2012, at 1:27 PM, Roger J wrote:
What are the issues that you are trying to correct? ; There are built in aids like calibration and no op.From: Thomas <troperecordings@...>
To: vintagesynthrepair@yahoogroups.com
Sent: Wednesday, December 5, 2012 3:51 AM
Subject: [vintagesynthrepair] OBXa diagnostic EPROM needed
Hi guys,
thanks for approving my membership to this list :-)
I'm restoring an Oberheim OBXa 8-voice and looking for the diagnostic EPROM with paperworks for it. A BIN would be fine.
It's REV C mainboards and has a Numera Midi interface installed.
Will probably remove the Numera first to get the machine up and running and see if it's the Numera that's causing trouble.
Fortunately all the voiceboards are fine.
Any help would be great and appreciated :-)
Best regards,
Thomas
Thomas P. HeckmannTrope Recordings - AFU Limited - AFULAB - trope mastering
Thomas P. Heckmann
Trope Recordings - AFU Limited - AFULAB - trope mastering