MXR Delay System II troubleshooting

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Ansur
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Joined: 03 Aug 2011, 07:09
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Post by Ansur »

Hi all,

My MXR Delay System 2 stopped doing what it should do - the signal still passes, but no delay is added.
The previous owner had it services by Charlie Chander. Capacitors and memory chips were replaced, this must have been around 8 years ago.

When I switch it on, delay shows around 2800ms, or around 1400 when I remove th extra memory module. No matter how I twist the knobs, it always stays around that same range.
I tried replacing the memory modules today, but no change whatsoever.

The only button that makes an impact is the dry defeat - no signal passes when it's pressed (which makes sense in a way since delay isn't working).
I'm far from an electronics expert, but I'm not afraid to get my hands dirty, so I want to see what I can do myself. Trouble is I don't really know where to start.
Given the age of this rack unit, there's not that muc info to be found neither. What would be the best place to start?

FYI for those interested, a schematic can be found here.

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