Chat about Equipment Info
 #165111  by PLS30820
 Tue Mar 12, 2019 5:35 pm
So, I was having some issues with my early 80's MXR analog delay (green monster), and I decided to open it up and see if I could spot anything. Needless to say, I believe I'll be sending this to MXR to see about getting it fixed (see pics). Thoughts?
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 #165112  by lovetoboogie
 Tue Mar 12, 2019 8:17 pm
Ha! Yes...that blue 400uf Filter/Decoupling cap is bad....replace that and it should spring to life.
 #165114  by lovetoboogie
 Tue Mar 12, 2019 8:40 pm
Searing75 wrote:
Tue Mar 12, 2019 8:20 pm
I wouldn’t think MXR would be willing to fix this though? They would tell you that they no longer support products this old. It’s an easy fix to DIY.
Exactly...I am not entirely sure Dunlop/MXR will take that on. But they do have a custom shop. John Pape at Whirlwind is a better bet for challenging MXR stuff. He designed all these.

I have changed that particular cap many times over the last few years as these era MXR Delays come of age, so to speak...
 #165117  by waldo041
 Wed Mar 13, 2019 8:37 am
i would venture to say that this is going to be an issue with many vintage pedals in the next 10 years. Those Electrolytic caps have a shelf life and i would advise not changing just that blown one in there. I would change them all! IMO

YMMV,

~waldo
 #165118  by lovetoboogie
 Wed Mar 13, 2019 10:29 am
waldo041 wrote:
Wed Mar 13, 2019 8:37 am
i would venture to say that this is going to be an issue with many vintage pedals in the next 10 years. Those Electrolytic caps have a shelf life and i would advise not changing just that blown one in there. I would change them all! IMO

YMMV,

~waldo
Ironically these first gen analog delays only have that one electrolytic in the power supply. The rest of the stages are decoupled by tants which will outlive the pedal.
 #165124  by waldo041
 Wed Mar 13, 2019 2:56 pm
lovetoboogie wrote:
Wed Mar 13, 2019 10:29 am
waldo041 wrote:
Wed Mar 13, 2019 8:37 am
i would venture to say that this is going to be an issue with many vintage pedals in the next 10 years. Those Electrolytic caps have a shelf life and i would advise not changing just that blown one in there. I would change them all! IMO

YMMV,

~waldo
Ironically these first gen analog delays only have that one electrolytic in the power supply. The rest of the stages are decoupled by tants which will outlive the pedal.

Thanks for the clarification. But the same is true, one or many, those are some old pedals and the reticon chips are rare.
~waldo
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 #165142  by PLS30820
 Thu Mar 14, 2019 3:45 pm
Thanks guys. I checked with Dunlop and they verified that they don't fix these pedals that were made by MXR before Dunlop bought them out. So if I acquire a new cap, it shouldn't be that hard to unsolder and resolder the new one in, right?
 #165143  by PLS30820
 Thu Mar 14, 2019 3:49 pm
lovetoboogie wrote:
Wed Mar 13, 2019 10:29 am
waldo041 wrote:
Wed Mar 13, 2019 8:37 am
i would venture to say that this is going to be an issue with many vintage pedals in the next 10 years. Those Electrolytic caps have a shelf life and i would advise not changing just that blown one in there. I would change them all! IMO

YMMV,

~waldo
Ironically these first gen analog delays only have that one electrolytic in the power supply. The rest of the stages are decoupled by tants which will outlive the pedal.
Waldo, so to whom could I send it to have all the stuff changed? Ideas?
 #165144  by TeeJay
 Thu Mar 14, 2019 4:09 pm
Waldo, so to whom could I send it to have all the stuff changed? Ideas?
I think if I followed correctly that is the only cap that really needs attention for that circuit.