OBERHEIM SYNTH

The battery backup remembers the calibration what is the battery voltage? If the battery is low or the memory has a problem the calibration will be lost. There could be an issue with the power supply that might affect the digital timing but the chance is remote. Have you verified the DC voltages and the AC ripple present on these lines? The 000 to 199 user presets are not erased if you do a reset and calibration. If they remain intact and the calibration keeps losing it then I would suspect the paging memory control is having issues with the saved calibration data. This could be an SRAM or addresss bit issue.


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> From: Andreas Östling <andreas85@...>
>To: oberheim@yahoogroups.com 
>Sent: Monday, August 12, 2013 12:34 PM
>Subject: [oberheim] Re: Pitch Problems on Matrix1000 with working chips (audio attached)
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>That is really useful info you provided there!
>Yes I've tried to use the voice chip test... (ext funct -> 7 -> enter -> enter (while "0" on display)) and then hit a note 6 times to run through the voices. I have the pitch error on all the voices... But then I did a Calibration, and after that an initialization and now the pitch problem is gone. It seems as if I have to redo it now and then (unreasonably often in my opinion). Is the calibration etc saved in memory and disappears if there is a problem with the battery? But the factory presets 200-> etc seem intact so shouldn't they disappear aswell if there is some problem with the battery? What could cause it to go back to being un-calibrated so quickly?    
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