From Oakley Sound via analogue Sent Sun, May 26th 2019, 14:29
From Oakley Sound via analogue Sent Sun, May 26th 2019, 14:29
Again, sorry my posts are not in the correct thread. The 444C is a CMOS SRAM, and has low standby current for battery operation. I only mentioned the 5114 because that's what the Synthex schematic shows. The 2114 is NMOS. The function is the same as the CMOS parts such as 444C or 5114, but it doesn't have the low current standby capability, so it's not suitable for battery backup operation. The Synthex schematic shows 2114's installed for the scratchpad RAM, which is not backed up, and CMOS RAMs for the sequencer and patch storage. If you look at the Synthex schematics in the service manual, you can see that the chips select to both the patch RAMs and the sequencer RAMs are fed through a CMOS gate that is powered from the battery. So I am pretty sure that the sequencer data was meant to be preserved with power off. With a DMM, you can confirm that four of the SRAM chips are powered when the synth is off and two (the 2114's) are not. I suggested that you do this check anyway, as there could be a problem with this circuitry. Bob Grieb --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus