MXR Dyna Comp Diode

[rtcook]

Hi all,

I am looking for information on a diode that is in my 81-82 Dyna Comp.  It is the one in the power supply circuit.  It was talked about in the archives and I responded there, but I'm not sure if anyone will see it.

http://www.diystompboxes.com/smfforum/index.php?topic=4688.0

Please review the thread.  Any information would be greatly appreciated.

Thanks,

Roger

[rtcook]

I believe I have found my answer.  I think this is a 1N270 Germanium diode.  I found one on Small Bear Electronics site and ordered some.  Like I said, I think these are correct.  Can anyone confirm?

Roger

[MartyMart]

Roger, it seems to be just polarity protection on the 9v+ line so would seem a little wasteful to use
a Ge diode here, a 1N914 or 4148 will be fine and is still a small "glass" diode so preserves the look
of the original .... right ?
MM.

[rtcook]

MM,

Thanks for the response.  You are correct that I want to keep the original look.  Trivial as it sounds, I want to do that because the pedal is really in pristine condition.
Like I said before, I think I identified the exact part as a 1N270 Ge Diode.  I ordered some from Small Bear.  They were cheap enough.  If its not exactly the same then I just go with it unless it is completely the wrong part.  You are also correct that is it protection for the 9V.  My pedal has the 9V battery and AC input.  Because this diode was bad, the pedal would not work with a battery, but will work on AC power.  Any thoughts on why this diode would fail?  Wrong AC voltage input?  If so, could it have caused any other damage?  I suppose its also possible that the diode just failed from age or even a drop or bump?  It looks fragile like a fuse.

Roger